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2,770	Anatomical Therapeutic Chemical Classification System	The Anatomical Therapeutic Chemical (ATC) Classification System is a drug classification system that classifies the active ingredients of drugs according to the organ or system on which they act and their therapeutic, pharmacological and chemical properties. Its purpose is an aid to monitor drug use and for research to improve quality medication use. It does not imply drug recommendation or efficacy. It is controlled by the World Health Organization Collaborating Centre for Drug Statistics Methodology (WHOCC), and was first published in 1976. ## Coding system {#coding_system} This pharmaceutical coding system divides drugs into different groups according to the organ or system on which they act, their therapeutic intent or nature, and the drug\'s chemical characteristics. Different brands share the same code if they have the same active substance and indications. Each bottom-level ATC code stands for a pharmaceutically used substance, or a combination of substances, in a single indication (or use). This means that one drug can have more than one code, for example acetylsalicylic acid (aspirin) has `{{ATC\|A01\|AD05}}`{=mediawiki} as a drug for local oral treatment, `{{ATC\|B01\|AC06}}`{=mediawiki} as a platelet inhibitor, and `{{ATC\|N02\|BA01}}`{=mediawiki} as an analgesic and antipyretic; as well as one code can represent more than one active ingredient, for example `{{ATC\|C09\|BB04}}`{=mediawiki} is the combination of perindopril with amlodipine, two active ingredients that have their own codes (`{{ATC\|C09\|AA04}}`{=mediawiki} and `{{ATC\|C08\|CA01}}`{=mediawiki} respectively) when prescribed alone. The ATC classification system is a strict hierarchy, meaning that each code necessarily has one and only one parent code, except for the 14 codes at the topmost level which have no parents. The codes are semantic identifiers, meaning they depict information by themselves beyond serving as identifiers (namely, the codes depict themselves the complete lineage of parenthood). As of 7 May 2020, there are 6,331 codes in ATC; the table below gives the count per level. ATC level Codes Different names/pharmaceuticals ----------- ------- --------------------------------- Level 1 14 14 Level 2 94 94 Level 3 267 262 Level 4 889 819 Level 5 5067 4363 ## History The ATC system is based on the earlier Anatomical Classification System, which is intended as a tool for the pharmaceutical industry to classify pharmaceutical products (as opposed to their active ingredients). This system, confusingly also called ATC, was initiated in 1971 by the European Pharmaceutical Market Research Association (EphMRA) and is being maintained by the EphMRA and Intellus. Its codes are organised into four levels. The WHO\'s system, having five levels, is an extension and modification of the EphMRA\'s. It was first published in 1976. ## Classification In this system, drugs are classified into groups at five different levels: ### First level {#first_level} The first level of the code indicates the anatomical main group and consists of one letter. There are 14 main groups: Code Contents ------- --------------------------------------------------------------------- A Alimentary tract and metabolism B Blood and blood forming organs C Cardiovascular system D Dermatologicals G Genito-urinary system and sex hormones H Systemic hormonal preparations, excluding sex hormones and insulins J Antiinfectives for systemic use L Antineoplastic and immunomodulating agents M Musculo-skeletal system N Nervous system P Antiparasitic products, insecticides and repellents R Respiratory system S Sensory organs V Various Example: C Cardiovascular system ### Second level {#second_level} The second level of the code indicates the therapeutic subgroup and consists of two digits. Example: C03 Diuretics ### Third level {#third_level} The third level of the code indicates the therapeutic/pharmacological subgroup and consists of one letter. Example: C03C High-ceiling diuretics ### Fourth level {#fourth_level} The fourth level of the code indicates the chemical/therapeutic/pharmacological subgroup and consists of one letter. Example: C03CA Sulfonamides ### Fifth level {#fifth_level} The fifth level of the code indicates the chemical substance and consists of two digits. Example: C03CA01 furosemide ## Other ATC classification systems {#other_atc_classification_systems} ### ATCvet The Anatomical Therapeutic Chemical Classification System for veterinary medicinal products (ATCvet) is used to classify veterinary drugs. ATCvet codes can be created by placing the letter Q in front of the ATC code of most human medications. For example, furosemide for veterinary use has the code QC03CA01. Some codes are used exclusively for veterinary drugs, such as QI Immunologicals, QJ51 Antibacterials for intramammary use or QN05AX90 amperozide. ### Herbal ATC (HATC) {#herbal_atc_hatc} The Herbal ATC system (HATC) is an ATC classification of herbal substances; it differs from the regular ATC system by using 4 digits instead of 2 at the 5th level group. The herbal classification is not adopted by WHO. The Uppsala Monitoring Centre is responsible for the Herbal ATC classification, and it is part of the WHODrug Global portfolio available by subscription. ## Defined daily dose {#defined_daily_dose} The ATC system also includes defined daily doses (DDDs) for many drugs. This is a measurement of drug consumption based on the usual daily dose for a given drug. According to the definition, \"\[t\]he DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults.\" ## Adaptations and updates {#adaptations_and_updates} National issues of the ATC classification, such as the German Anatomisch-therapeutisch-chemische Klassifikation mit Tagesdosen, may include additional codes and DDDs not present in the WHO version. ATC follows guidelines in creating new codes for newly approved drugs. An application is submitted to WHO for ATC classification and DDD assignment. A preliminary or temporary code is assigned and published on the website and in the WHO Drug Information for comment or objection. New ATC/DDD codes are discussed at the semi-annual Working Group meeting. If accepted it becomes a final decision and published semi-annually on the website and WHO Drug Information and implemented in the annual print/on-line ACT/DDD Index on January 1. Changes to existing ATC/DDD follow a similar process to become temporary codes and if accepted become a final decision as ATC/DDD alterations. ATC and DDD alterations are only valid and implemented in the coming annual updates; the original codes must continue until the end of the year. An updated version of the complete on-line/print ATC index with DDDs is published annually on January 1.	2025-06-20T00:00:00
2,783	Atari Lynx	The Atari Lynx is a fourth-generation hand-held game console released by Atari Corporation in September 1989 in North America and 1990 in Europe and Japan. It was the first handheld game console with a color liquid-crystal display. Powered by a 4 MHz 65C02 8-bit CPU and a custom 16-bit blitter, the Lynx was more advanced than Nintendo\'s monochrome Game Boy, released two months earlier. It also competed with Sega\'s Game Gear and NEC\'s TurboExpress, released the following year. The system was developed at Epyx by two former designers of the Amiga personal computers. The project was called the Handy Game or simply Handy. In 1991, Atari replaced the Lynx with a smaller model internally referred to as the Lynx II. Atari published a total of 73 games for the Lynx before it was discontinued in 1995. ## History The Lynx system was originally developed by Epyx as the Handy Game. In 1986, two former Amiga designers, RJ Mical and Dave Needle, had been asked by a former manager at Amiga, Dave Morse, to design a portable gaming system. Morse now worked at Epyx, a game software company with a recent string of hit games. Morse\'s son had asked him if he could make a portable gaming system, prompting a meeting with Mical and Needle to discuss the idea. Morse convinced Mical and Needle and they were hired by Epyx to be a part of the design team. Planning and design of the console began in 1986 and was completed in 1987. Epyx first showed the Handy system at the Winter Consumer Electronics Show (CES) in January 1989. Facing financial difficulties, Epyx sought partners. Nintendo, Sega, and other companies declined, but Atari and Epyx eventually agreed that Atari would handle production and marketing, and Epyx would handle software development. Epyx declared bankruptcy by the end of the year, so Atari essentially owned the entire project. Both Atari and others had to purchase Amigas from Atari arch-rival Commodore in order to develop Lynx software. The Handy was designed to run games from the cartridge format, and the game data must be copied from ROM to RAM before it can be used. Thus, less RAM is then available and each game\'s initial loading is slow. There are trace remnants of a cassette tape interface physically capable of being programmed to read a tape. Lynx developers have noted that \"there is still reference of the tape and some hardware addresses\" and an updated vintage Epyx manual describes the bare existence of what could be utilized for tape support. A 2009 retrospective interview with Mical clarifies that there is no truth to some early reports claiming that games were loaded from tape, and elaborates, \"We did think about hard disk a little.\" The networking system was originally developed to run over infrared links and codenamed RedEye. This was changed to a cable-based networking system before the final release as the infrared beam was too easily interrupted when players walked through the beam, according to Peter Engelbrite. Engelbrite developed the first recordable eight-player co-op game, and the only eight-player game for the Lynx, Todd\'s Adventures in Slime World. Atari changed the internal speaker and removed the thumb stick on the control pad. At Summer 1989 CES, Atari\'s press demonstration included the \"Portable Color Entertainment System\", which was changed to \"Lynx\" when distributed to resellers, initially retailing in the US at `{{US$\|179.95\|1989\|about=yes\|round=-1}}`{=mediawiki}. Its launch was successful. Atari reported that it had sold 90% of the 50,000 units shipped in the launch month in the U.S. with a limited launch in New York. US sales in 1990 were approximately 500,000 units according to the Associated Press. In late 1991, it was reported that Atari sales estimates were about 800,000, which Atari claimed was within its expected projections.`{{failed verification\|reason=No mention of Lynx sales estimates found at that areference\|date=October 2022}}`{=mediawiki} Lifetime sales by 1995 amount to fewer than 7 million units when combined with the Game Gear. In comparison, 16 million Game Boy units were sold by 1995 because of its superior durability, pricing, battery life, and game library, notably the pack-in hit Tetris.`{{r\|maher20161222}}`{=mediawiki} As with the console units, the game cartridge design evolved over the first year of the console\'s release. The first generation of cartridges are flat, and designed to be stackable for ease of storage. However, this design proved to be very difficult to remove from the console and was replaced by a second design. This style, called \"tabbed\" or \"ridged\", adds two small tabs on the underside to aid in removal. The original flat style cartridges can be stacked on top of the newer cartridges, but the newer cartridges can not be easily stacked on each other, nor were they stored easily. Thus a third style, the \"curved lip\" style was produced, and all official and third-party cartridges during the console\'s lifespan were released (or re-released) using this style. In May 1991, Sega launched its Game Gear portable gaming handheld with a color screen. In comparison to the Lynx it had shorter battery life (3--4 hours as opposed to 4-5 for the Lynx), but it is slightly smaller, has significantly more games, and cost \$30 less than the Lynx at launch. Retailers such as Game and Toys \"R\" Us continued to sell the Lynx well into the mid-1990s on the back of the Atari Jaguar launch, helped by magazines such as Ultimate Future Games which continued to cover the Lynx alongside the new generation of 32-bit and 64-bit consoles. ### Lynx II {#lynx_ii} In July 1991, Atari introduced a new version of the Lynx, internally called the \"Lynx II\", with a new marketing campaign, new packaging, slightly improved hardware, better battery life, and a sleeker look. It has rubber hand grips and a clearer backlit color screen with a power save option (which turns off the backlighting). The monaural headphone jack of the original Lynx was replaced with one wired for stereo. The Lynx II was available without any accessories, dropping the price to `{{US$\|99\|1990\|long=no\|round=-1}}`{=mediawiki}. ### Decline In 1993, Atari started shifting its focus away from the Lynx in order to prepare for the launch of the Jaguar; a few games were released during that time, including Battlezone 2000. Support for the Lynx was formally discontinued in 1995. After the respective launches of the Sega Saturn and Sony PlayStation caused the commercial failure of the Jaguar, Atari ceased all game development and hardware manufacturing by early 1996 and would later merge with JTS, Inc. on July 30 of that year. ## Features The Atari Lynx has a backlit color LCD display, switchable right- and left-handed (upside down) configuration, and the ability to network with other units via Comlynx cable. The maximum stable connection allowed is eight players. Each Lynx needs a copy of the game, and one cable can connect two machines. The cables can be connected into a chain. The Lynx was cited as the \"first gaming console with hardware support for zooming and distortion of sprites\". With a 4096 color palette and integrated maths and graphics co-processors (including a sprite engine unit), its color graphics display was said to be the key defining feature in the system\'s competition against Nintendo\'s monochromatic Game Boy. The fast pseudo-3D graphics features were made possible on a minimal hardware system by co-designer Dave Needle having \"invented the technique for planar expansion/shrinking capability\" and using stretched triangles instead of full polygons. ## Technical specifications {#technical_specifications} - Mikey (8-bit VLSI custom CMOS chip running at 16 MHz) - On Lynx I a VLSI 8-bit VL65NC02 processor (based on the MOS 6502) running at up to 4 MHz (3.6 MHz average). In the stereo version of Lynx II a 65C02 with all instructions. - Sound engine - 4 channel sound - 8-bit DAC for each channel (4 channels × 8-bits/channel = 32 bits commonly quoted) these four sound channels can also switch in analogue sound mode to generate PSG sound. - Video DMA driver for liquid-crystal display - Custom built and designed by Jay Miner and Dave Morse - 160×102 pixels resolution - 4,096 color (12-bit) palette - 16 simultaneous colors (4 bits) from palette per scanline - Variable frame rate (up to 75 frames/second) - Eight system timers (two reserved for LCD timing, one for UART) - Interrupt controller - UART (for Comlynx) (fixed format 8E1, up to 62500 Bd / TurboMode 1,000,000Bd) - 512 bytes of bootstrap and game-card loading ROM - Suzy (16-bit VLSI custom CMOS chip running at `{{nowrap\|16 MHz}}`{=mediawiki}) - Unlimited number of blitter \"sprites\" with collision detection - Hardware sprite scaling, distortion, and tilting effects - Hardware decoding of compressed sprite data - Hardware clipping and multi-directional scrolling - Math engine - Hardware 16-bit × 16-bit → 32-bit multiply with optional accumulation; 32-bit ÷ 16-bit → 16-bit divide - Parallel processing of CPU - RAM: 64 KB 120ns DRAM - Cartridges: 128, 256, 512 KB and (with bank-switching) 1 MB - Ports: - Headphone port (`{{nowrap\|3.5 mm}}`{=mediawiki} stereo; wired for mono on the original Lynx) - ComLynx (multiple unit communications, serial) - LCD Screen: 3.5\" diagonal - Battery holder (six AA) 4--5 hours (Lynx I) 5--6 hours (Lynx II) ## Legacy Telegames released several games in the late 1990s, including a port of Raiden and a platformer called Fat Bobby in 1997, and an action sports game called Hyperdrome in 1999. On March 13, 1998, nearly three years after the Lynx\'s discontinuation, JTS Corporation sold all of the Atari assets to Hasbro Interactive for \$5 million. On May 14, 1999, Hasbro, which held on to those properties until selling Hasbro Interactive to Infogrames in 2001, released into the public domain all rights to the Jaguar, opening up the platform for anyone to publish software on without Hasbro\'s interference. Internet theories say that the Lynx\'s rights may have been released to the public at the same time as the Jaguar, but this is clearly disputed. Nevertheless, since discontinuation, the Lynx, like the Jaguar, has continued to receive support from a grassroots community which would go on to produce many successful homebrew games such as T-Tris (the first Lynx game with a save-game feature), Alpine Games, and Zaku. In 2008, Atari was honored at the 59th Annual Technology & Engineering Emmy Awards for pioneering the development of handheld games with the Lynx. In 2022, the compilation Atari 50 released with a handful of popular Lynx titles, marking the first time that classic Lynx software would be officially rereleased by Atari. A collection of Lynx games have also been released as standalone titles outside of the Atari 50 compilation as well on other platforms such as Steam and the Evercade.	2025-06-20T00:00:00
2,784	Ahimsa	`{{transliteration\|sa\|Ahimsa}}`{=mediawiki} (अहिंसा, IAST: `{{IAST\|ahiṃsā}}`{=mediawiki}, `{{lit\|nonviolence}}`{=mediawiki}) is the ancient Indian principle of nonviolence which applies to actions towards all living beings. It is a key virtue in Indian religions like Jainism, Buddhism and Hinduism. (also spelled Ahinsa) is one of the cardinal virtues of Jainism, where it is the first of the Pancha Mahavrata. It is also one of the central precepts of Hinduism and is the first of the five precepts of Buddhism. `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is inspired by the premise that all living beings have the spark of the divine spiritual energy; therefore, to hurt another being is to hurt oneself. `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is also related to the notion that all acts of violence have karmic consequences. While ancient scholars of Brahmanism had already investigated and refined the principles of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, the concept reached an extraordinary development in the ethical philosophy of Jainism. Mahavira, the twenty-fourth and the last `{{transliteration\|sa\|[[tirthankara]]}}`{=mediawiki} of Jainism, further strengthened the idea in `{{BCE\|the 6th century}}`{=mediawiki}. About `{{CE\|the 5th century}}`{=mediawiki}, Valluvar emphasized `{{transliteration\|sa\|ahimsa}}`{=mediawiki} and moral vegetarianism as virtues for an individual, which formed the core of his teachings in the Kural. Perhaps the most popular advocate of the principle of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} in modern times was Mohandas K. Gandhi. \'s precept that humans should \'cause no injury\' to another living being includes one\'s deeds, words, and thoughts. Classical Hindu texts like the Mahabharata and the Ramayana, as well as modern scholars, disagree about what the principle of `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} dictates when one is faced with war and other situations that require self-defence. In this way, historical Indian literature has contributed to modern theories of just war and self-defence. ## Etymology The word `{{transliteration\|sa\|Ahimsa}}`{=mediawiki}---sometimes spelled `{{transliteration\|sa\|Ahinsa}}`{=mediawiki}---is derived from the Sanskrit root `{{transliteration\|sa\|hiṃs}}`{=mediawiki}, meaning to strike; `{{transliteration\|sa\|hiṃsā}}`{=mediawiki} is injury or harm, while `{{transliteration\|sa\|a-hiṃsā}}`{=mediawiki} (prefixed with the alpha privative), its opposite, is non-harming or nonviolence. ## Origins Reverence for `{{transliteration\|sa\|ahimsa}}`{=mediawiki} can be found in Jain, Hindu, and Buddhist canonical texts. Lord Parshvanatha (the 23rd of 24 Tirthankaras of Jainism) is said to have preached `{{transliteration\|sa\|ahimsa}}`{=mediawiki} as one of the four vows. No other Indian religion has developed the non-violence doctrine and its implications on everyday life as much as has Jainism. ## Hinduism ### Ancient Vedic texts {#ancient_vedic_texts} as an ethical concept evolved in the Vedic texts. The oldest scriptures indirectly mention `{{transliteration\|sa\|Ahimsa}}`{=mediawiki}. Over time, the Hindu scripts revised ritual practices, and the concept of `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} was increasingly refined and emphasized until `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} became the highest virtue by the late Vedic era (about `{{BCE\|1000-600}}`{=mediawiki}). For example, hymn 10.22.25 in the Rig Veda uses the words `{{transliteration\|sa\|[[Satya]]}}`{=mediawiki} (truthfulness) and `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} in a prayer to deity Indra; later, the Yajur Veda dated to be between `{{BCE\|1200}}`{=mediawiki} and `{{BCE\|900}}`{=mediawiki}, states, \"may all beings look at me with a friendly eye, may I do likewise, and may we look at each other with the eyes of a friend\".`{{page needed\|date=November 2023}}`{=mediawiki}`{{page needed\|date=November 2023}}`{=mediawiki} The term `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} appears in the text Taittiriya Shakha of the Yajurveda (TS 5.2.8.7), where it refers to non-injury to the sacrificer himself. It occurs several times in the Shatapatha Brahmana in the sense of \"non-injury\". The `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} doctrine is a late Vedic era development in Brahmanical culture. The earliest reference to the idea of non-violence to animals (`{{transliteration\|sa\|pashu-Ahimsa}}`{=mediawiki}), apparently in a moral sense, is in the Kapisthala Katha Samhita of the Yajurveda (KapS 31.11), which may have been written in about `{{BCE\|1500-1200}}`{=mediawiki}.`{{page needed\|date=November 2023}}`{=mediawiki}`{{page needed\|date=November 2023}}`{=mediawiki} The Chandogya Upanishad (3.17.4) includes ahimsa in its list of virtues. John Bowker states the word appears but is uncommon in the principal Upanishads. Kaneda gives examples of the word `{{transliteration\|sa\|pashu-Ahimsa}}`{=mediawiki} in these Upanishads. Other scholars suggest `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} as an ethical concept started evolving in the Vedas, becoming an increasingly central concept in Upanishads. The Chāndogya Upaniṣad, dated to `{{BCE\|800 to 600}}`{=mediawiki}, one of the oldest Upanishads, has the earliest evidence for the Vedic era use of the word `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} in the sense familiar in Hinduism (a code of conduct). It bars violence against \"all creatures\" (`{{transliteration\|sa\|sarvabhuta}}`{=mediawiki}), and the practitioner of `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is said to escape from the cycle of rebirths (CU 8.15.1). Some scholars state that this mention may have been an influence of Jainism on Vedic Hinduism. Others scholar state that this relationship is speculative, and though Jainism is an ancient tradition the oldest traceable texts of Jainism tradition are from many centuries after the Vedic era ended. Chāndogya Upaniṣad also names `{{transliteration\|sa\|Ahimsa}}`{=mediawiki}, along with `{{transliteration\|sa\|Satyavacanam}}`{=mediawiki} (truthfulness), `{{transliteration\|sa\|Ārjavam}}`{=mediawiki} (sincerity), `{{transliteration\|sa\|[[Dāna]]m}}`{=mediawiki} (charity), and `{{transliteration\|sa\|[[Tapas (Indian religions)\|Tapo]]}}`{=mediawiki} (penance/meditation), as one of five essential virtues (CU 3.17.4). The Sandilya Upanishad lists ten forbearances: `{{transliteration\|sa\|Ahimsa}}`{=mediawiki}, `{{transliteration\|sa\|Satya}}`{=mediawiki}, `{{transliteration\|sa\|Asteya}}`{=mediawiki}, `{{transliteration\|sa\|Brahmacharya}}`{=mediawiki}, `{{transliteration\|sa\|Daya}}`{=mediawiki}, `{{transliteration\|sa\|Arjava}}`{=mediawiki}, `{{transliteration\|sa\|Kshama}}`{=mediawiki}, `{{transliteration\|sa\|Dhriti}}`{=mediawiki}, `{{transliteration\|sa\|Mitahara}}`{=mediawiki}, and `{{transliteration\|sa\|Saucha}}`{=mediawiki}. According to Kaneda, the term `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is an important spiritual doctrine shared by Hinduism, Buddhism, and Jainism. It means \'non-injury\' and \'non-killing\'. It implies the total avoidance of harming any living creature by deeds, words, and thoughts. ### The Epics {#the_epics} The Mahabharata, one of the epics of Hinduism, has multiple mentions of the phrase `{{transliteration\|sa\|Ahimsa Paramo Dharma}}`{=mediawiki} (अहिंसा परमॊ धर्मः), which literally means: non-violence is the highest moral virtue. For example, Anushasana Parva has the verse: > अहिंसा परमॊ धर्मः तथाहिंसा परॊ दमः। अहिंसा परमं दानम् अहिंसा परमस तपः। अहिंसा परमॊ यज्ञः तथाहिस्मा परं बलम्। अहिंसा परमं मित्रम् अहिंसा परमं सुखम्। अहिंसा परमं सत्यम् अहिंसा परमं श्रुतम्॥ The above passage from Mahabharata emphasises the cardinal importance of `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} in Hinduism, and literally means: > `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the highest `{{transliteration\|sa\|[[Dharma]]}}`{=mediawiki}, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the highest self-control, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the greatest gift, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the best practice, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the highest sacrifice, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the finest strength, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the greatest friend, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the greatest happiness, `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the highest truth, and `{{transliteration\|sa\|Ahimsa}}`{=mediawiki} is the greatest teaching. Some other examples where the phrase `{{transliteration\|sa\|Ahimsa Paramo Dharma}}`{=mediawiki} are discussed include Adi Parva, Vana Parva, and Anushasana Parva. The Bhagavad Gita, among other things, discusses the doubts and questions about appropriate response when one faces systematic violence or war. These verses develop the concepts of lawful violence in self-defence and the theories of just war. However, there is no consensus on this interpretation. Gandhi, for example, considers this debate about non-violence and lawful violence as a mere metaphor for the internal war within each human being, when he or she faces moral questions. ### Self-defence, criminal law, and war {#self_defence_criminal_law_and_war} The classical texts of Hinduism devote numerous chapters to discussing what people who practice the virtue of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} can and must do when faced with war, violent threat, or the need to sentence someone convicted of a crime. These discussions have led to theories of just war, ideas of reasonable self-defense, and views of proportionate punishment. Arthashastra discusses, among other things, what constitutes proportionate response and punishment. War The precepts of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} in Hinduism require that war must be avoided, with`{{ambiguous\|reason=unclear if this means that Hinduism, with S&TD, requires this; or if S&TD is the method for avoiding war; or if S&TD is the alternative to war\|date=July 2023}}`{=mediawiki} sincere and truthful dialogue. Force must be the last resort. If war becomes necessary, its cause must be just, its purpose virtuous, its objective to restrain the wicked, its aim peace, and its method lawful. War can only be started and stopped by a legitimate authority. Weapons must be proportionate to the opponent and the aim of war, not indiscriminate tools of destruction. All strategies and weapons used in the war must be to defeat the opponent, not to cause misery to the opponent; for example, the use of arrows is allowed, but the use of arrows smeared with painful poison is not allowed. Warriors must use judgment`{{Specify\|reason=what sort, in what way, to what end?\|date=July 2023}}`{=mediawiki} in the battlefield. Cruelty to the opponent during war is forbidden. Wounded, unarmed opponent warriors must not be attacked or killed; they must be brought to your realm and given medical treatment. Children, women, and civilians must not be injured. While the war is in progress, sincere dialogue for peace must continue. Self-defence Different interpretations of ancient Hindu texts have been offered in matters of self-defense. For example, Tähtinen suggests self-defense is appropriate, criminals are not protected by the rule of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, and Hindu scriptures support violence against an armed attacker. `{{transliteration\|sa\|ahimsa}}`{=mediawiki} is not meant to imply pacifism. Alternative theories of self-defense, inspired by `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, build principles similar to ideas of just war. Aikido, pioneered in Japan, illustrates one such set of principles for self-defense. Morihei Ueshiba, the founder of Aikido, described his inspiration as Ahimsa. According to this interpretation of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} in self-defense, one must not assume that the world is free of aggression. One must presume that some people will, out of ignorance, error, or fear, attack others or intrude into their space, physically or verbally. The aim of self-defense, suggested Ueshiba, must be to neutralize the attacker\'s aggression and avoid conflict. The best defense is one with which the victim is protected and the attacker is respected and not injured if possible. Under `{{transliteration\|sa\|ahimsa}}`{=mediawiki} and Aikido, there are no enemies, and appropriate self-defense focuses on neutralizing the immaturity, assumptions, and aggressive strivings of the attacker. Criminal law Tähtinen concludes that Hindus have no misgivings about the death penalty; their position is that evil-doers who deserve death should be killed and that a king, in particular, is obliged to punish criminals and should not hesitate to kill them, even if they happen to be his brothers and sons. Other scholars conclude that Hindu scriptures suggest that sentences for any crime must be fair, proportional, and not cruel. ### Non-human life {#non_human_life} thumb\\|upright=0.8\\|The 5th-century CE Tamil scholar Valluvar, in his Tirukkural, taught `{{transliteration\|sa\|ahimsa}}`{=mediawiki} and moral vegetarianism as personal virtues. The plaque in this statue of Valluvar at an animal sanctuary at Tiruvallur describes the Kural\'s teachings on `{{transliteration\|sa\|ahimsa}}`{=mediawiki} and non-killing, summing them up with the definition of veganism. The Hindu precept of \"cause no injury\" applies to animals and all life forms. This precept is not found in the oldest verses of Vedas (`{{BCE\|1500–1000}}`{=mediawiki}), but increasingly becomes one of the central ideas in post-Vedic period. In the oldest layer of the Vedas, such as the Rigveda, ritual sacrifices of animals and cooking of meat to feed guests are mentioned. This included goat, ox, horse, and others. However, the text is not uniform in its prescriptions. Some verses praise meat as food, while other verses in the Vedas recommend \"abstention from meat\", in particular, \"beef\". According to Marvin Harris, the Vedic literature is inconsistent, with some verses suggesting ritual slaughter and meat consumption, while others suggesting a taboo on meat-eating. Hindu texts dated to `{{BCE\|1st millennium}}`{=mediawiki} initially mention meat as food, then evolve to suggest that only meat obtained through ritual sacrifice can be eaten, thereafter evolving to the stance that one should eat no meat because it hurts animals, with verses describing the noble life as one that lives on flowers, roots, and fruits alone. The late Vedic-era literature (`{{BCE\|pre-500}}`{=mediawiki}) condemns all killings of men, cattle, birds, and horses, and prays to god Agni to punish those who kill. Later texts of Hinduism declare `{{transliteration\|sa\|ahimsa}}`{=mediawiki} as one of the primary virtues, declare any killing or harming any life as against `{{transliteration\|sa\|dharma}}`{=mediawiki} (moral life). Finally, the discussion in the Upanishads and Hindu Epics shifts to whether a human being can ever live his or her life without harming animal and plant life in some way, which and when plants or animal meat may be eaten, whether violence against animals causes human beings to become less compassionate, and if and how one may exert least harm to non-human life consistent with `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, given the constraints of life and human needs. The Mahabharata permits hunting by warriors, but opposes it in the case of hermits who must be strictly non-violent. Sushruta Samhita, a Hindu text written in `{{BCE\|the 3rd or 4th century}}`{=mediawiki}, in Chapter XLVI suggests proper diet as a means of treating certain illnesses, and recommends various fishes and meats for different ailments and for pregnant women, and the Charaka Samhita describes meat as superior to all other kinds of food for convalescents. Across the texts of Hinduism, there is a profusion of ideas about the virtue of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} when applied to non-human life, but without a universal consensus. Alsdorf claims the debate and disagreements between supporters of vegetarian lifestyle and meat eaters was significant. Even suggested exceptions -- ritual slaughter and hunting -- were challenged by advocates of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}. In the Mahabharata both sides present various arguments to substantiate their viewpoints. Moreover, a hunter defends his profession in a long discourse. Many of the arguments proposed in favor of non-violence to animals refer to the bliss one feels, the rewards it entails before or after death, the danger and harm it prevents, as well as to the karmic consequences of violence. The ancient Hindu texts discuss `{{transliteration\|sa\|ahimsa}}`{=mediawiki} and non-animal life. They discourage wanton destruction of nature including of wild and cultivated plants. Hermits (sannyasins) were urged to live on a fruitarian diet so as to avoid the destruction of plants. Scholars`{{r\|CCEN}}`{=mediawiki} claim the principles of ecological nonviolence are innate in the Hindu tradition, and its conceptual fountain has been `{{transliteration\|sa\|ahimsa}}`{=mediawiki} as its cardinal virtue. The classical literature of the Indian religions, such as Hinduism and Jainism, exists in many Indian languages. For example, the Tirukkural, written in three volumes, likely between `{{CE\|450 and 500}}`{=mediawiki}, dedicates verses 251--260 and 321--333 of its first volume to the virtue of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, emphasizing on moral vegetarianism and non-killing (`{{transliteration\|sa\|kollamai}}`{=mediawiki}). However, the Tirukkural also glorifies soldiers and their valour during war, and states that it is king\'s duty to punish criminals and implement \"death sentence for the wicked\". In 1960, H. Jay Dinshah founded the American Vegan Society (AVS), linking veganism to the concept of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}. ### Modern times {#modern_times} In the 19th and 20th centuries, prominent figures of Indian spirituality such as Shrimad Rajchandra and Swami Vivekananda emphasised the importance of Ahimsa. Mohandas Karamchand Gandhi successfully promoted the principle of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} to all spheres of life, in particular to politics (`{{transliteration\|sa\|[[Swaraj]]}}`{=mediawiki}). His non-violent resistance movement `{{transliteration\|sa\|[[satyagraha]]}}`{=mediawiki} had an immense impact on India, impressed public opinion in Western countries, and influenced the leaders of various civil and political rights movements such as the American civil rights movement\'s Martin Luther King Jr. and James Bevel. In Gandhi\'s thought, `{{transliteration\|sa\|ahimsa}}`{=mediawiki} precludes not only the act of inflicting a physical injury but also mental states like evil thoughts and hatred, and unkind behavior such as harsh words, dishonesty, and lying, all of which he saw as manifestations of violence incompatible with `{{transliteration\|sa\|ahimsa}}`{=mediawiki}. Gandhi believed `{{transliteration\|sa\|ahimsa}}`{=mediawiki} to be a creative energy force, encompassing all interactions leading one\'s self to find `{{transliteration\|sa\|satya}}`{=mediawiki}, \"Divine Truth\". Sri Aurobindo criticized the Gandhian concept of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} as unrealistic and not universally applicable; he adopted a pragmatic non-pacifist position, saying that the justification of violence depends on the specific circumstances of the given situation. Gandhi took the religious principle of ahimsa, and turned it into a non-violent tool for mass action. He used it to fight not only colonial rule, but social evils such as racial discrimination and untouchability as well. Gandhi stated his belief that \"`{{transliteration\|sa\|[a]himsa}}`{=mediawiki} is in Hinduism, it is in Christianity as well as in Islam.\" He added, \"Nonviolence is common to all religions, but it has found the highest expression and application in Hinduism (I do not regard Jainism or Buddhism as separate from Hinduism).\" When questioned whether violence and nonviolence are taught in Quran, he stated, \"I have heard from many Muslim friends that the Koran teaches the use of nonviolence. (\... The) argument about nonviolence in the Holy Koran is an interpolation, not necessary for my thesis.\" Studying `{{transliteration\|sa\|ahimsa}}`{=mediawiki}\'s history and philosophy influenced Albert Schweitzer\'s principle of \"reverence for life\". He commended Indian traditions for their ethics of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, considering the prohibition against killing and harming \"one of the greatest events in the spiritual history of humankind\". However, he noted that \"not-killing\" and \"not-harming\" might be unfeasible in certain situations, like self-defense, or ethically complex, as in cases of prolonged famine. ### Yoga means \"abstinence from malice towards all living creatures in every way and at all times\". Ahimsa is imperative for practitioners of Patañjali\'s eight limb Raja yoga system. It is included in the first limb and is the first of five `{{transliteration\|sa\|[[Yamas]]}}`{=mediawiki} (self restraints) which, together with the second limb, make up the code of ethical conduct in Yoga philosophy.Sanskrit Original with Translation 1: - Translation 2: - Translation 3: Commentators on the Yoga Sutras II.30 emphasize that ahimsa is the most important and foundational yama of the five yamas. Vijnanabhiksu uses the analogy of an elephant to convey its importance, while Vyasa defines it as refraining from harming any living being at any time, emphasizing that all other yamas support and purify ahimsa. is also one of the ten `{{transliteration\|sa\|Yamas}}`{=mediawiki} in Hatha Yoga according to verse 1.1.17 of its classic manual Hatha Yoga Pradipika. The significance of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} as the first restraint in the first limb of Yoga (`{{transliteration\|sa\|Yamas}}`{=mediawiki}) is that it defines the necessary foundation for progress through Yoga. It is a precursor to `{{transliteration\|sa\|Asana}}`{=mediawiki}, implying that success in `{{transliteration\|sa\|Yogasana}}`{=mediawiki} can be had only if the self is purified in thought, word, and deed through the self-restraint of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}. ## Jainism In Jainism, the understanding and implementation of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} is more radical, scrupulous, and comprehensive than in any other religion. Killing any living being out of passions like attachment is considered `{{transliteration\|sa\|hiṃsā}}`{=mediawiki} (to injure) and abstaining from such an act is `{{transliteration\|sa\|ahimsā}}`{=mediawiki} (noninjury). The vow of `{{transliteration\|sa\|ahimsā}}`{=mediawiki} is considered the foremost among the \"five vows of Jainism\". Other vows like truth (`{{transliteration\|sa\|satya}}`{=mediawiki}) are meant for safeguarding the vow of `{{transliteration\|sa\|ahimsā}}`{=mediawiki}. In the practice of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, the requirements are less strict for the lay persons (`{{transliteration\|sa\|[[sravakas]]}}`{=mediawiki}) who have undertaken `{{transliteration\|sa\|anuvrata}}`{=mediawiki} (Smaller Vows) than for the Jain monastics who are bound by the Mahavrata \"Great Vows\". The statement `{{IAST\|ahimsā paramo dharmaḥ}}`{=mediawiki} (or, \"Non-injury/nonviolence/harmlessness is the supreme/ultimate/paramount/highest/absolute duty/virtue/attribute/religion\"`{{refn\|slashes are used here to present alternative denotations}}`{=mediawiki}) is often found inscribed on the walls of the Jain temples. As in Hinduism, the aim is to prevent the accumulation of harmful karma. When Mahavira revived and reorganised the Jain faith in `{{BCE\|the 6th or 5th century}}`{=mediawiki}, `{{transliteration\|sa\|ahimsa}}`{=mediawiki} was already an established, strictly observed rule. Rishabhanatha (Ādinātha), the first Jain Tirthankara, whom modern Western historians consider to be a historical figure, followed by Parshvanatha (Pārśvanātha) the twenty-third Tirthankara lived in about `{{BCE\|the 9th century}}`{=mediawiki}. He founded the community to which Mahavira\'s parents belonged. Ahimsa was already part of the \"Fourfold Restraint\" (Caujjama), the vows taken by Parshva\'s followers. In the times of Mahavira and in the following centuries, Jains were at odds with both Buddhists and followers of the Vedic religion or Hindus, whom they accused of negligence and inconsistency in the implementation of `{{transliteration\|sa\|ahimsa}}`{=mediawiki}. According to the Jain tradition either lacto vegetarianism or veganism is prescribed. The Jain concept of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} is characterised by several aspects. Killing of animals for food is absolutely ruled out. Jains also make considerable efforts not to injure plants in everyday life as far as possible. Though they admit that plants must be destroyed for the sake of food, they accept such violence only inasmuch as it is indispensable for human survival, and there are special instructions for preventing unnecessary violence against plants. Jain monks and nuns go out of their way so as not to hurt even small insects and other minuscule animals. Both the renouncers and the laypeople of Jain faith reject meat, fish, alcohol, and honey as these are believed to harm large or minuscule life forms. Jain scholars have debated the potential injury to other life forms during one\'s occupation. Certain Jain texts (according to Padmanabh Jaini, a Jainism scholar) forbid people of its faith from husbandry, agriculture, and trade in animal-derived products. Some Jains abstain from farming because it inevitably entails unintentional killing or injuring of many small animals, such as worms and insects. These teachings, in part, have led the Jain community to focus on trade, merchant, clerical, and administrative occupations to minimize `{{transliteration\|sa\|arambhaja-himsa}}`{=mediawiki} (occupational violence against all life forms). For the layperson, the teaching has been of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} with `{{transliteration\|sa\|pramada}}`{=mediawiki} -- that is, reducing violence through proper intention and being careful in every action on a daily basis to minimize violence to all life forms. The Jain texts, unlike most Hindu and Buddhist texts on just war, have been inconsistent. For its monastic community -- `{{transliteration\|sa\|[[sadhu]]}}`{=mediawiki} and `{{transliteration\|sa\|[[sadhu\|sadhvi]]}}`{=mediawiki} -- the historically accepted practice has been to \"willingly sacrifice one\'s own life\" to the attacker, to not retaliate, so that the mendicant may keep the First Great Vow of \"total nonviolence\". Jain literature of `{{CE\|the 10th century}}`{=mediawiki}, for example, describes a king ready for war and being given lessons about non-violence by the Jain acharya (spiritual teacher). In `{{CE\|the 12th century}}`{=mediawiki} and thereafter, in an era of violent raids, destruction of temples, the slaughter of agrarian communities and ascetics by Islamic armies, Jain scholars reconsidered the First Great Vow of mendicants and its parallel for the laypeople. The medieval texts of this era, such as by Jinadatta Suri, recommended both the mendicants and the laypeople to fight and kill if that would prevent greater and continued violence on humans and other life forms (`{{transliteration\|sa\|virodhi-himsa}}`{=mediawiki}). Such exemptions to `{{transliteration\|sa\|ahimsa}}`{=mediawiki} is a relatively rare teaching in Jain texts, states Dundas. Mahatma Gandhi stated, \"No religion in the World has explained the principle of `{{transliteration\|sa\|Ahiṃsā}}`{=mediawiki} so deeply and systematically as is discussed with its applicability in every human life in Jainism. As and when the benevolent principle of `{{transliteration\|sa\|Ahiṃsā}}`{=mediawiki} or non-violence will be ascribed for practice by the people of the world to achieve their end of life in this world and beyond, Jainism is sure to have the uppermost status and Mahāvīra is sure to be respected as the greatest authority on `{{transliteration\|sa\|Ahiṃsā}}`{=mediawiki}\". ## Buddhism Further information: Noble Eightfold Path, Buddhist ethics#Killing, causing others to kill, Buddhism and violence, Engaged Buddhism In Buddhist texts `{{transliteration\|sa\|ahimsa}}`{=mediawiki} (or its Pāli cognate `{{transliteration\|pi\|avihiṃsā}}`{=mediawiki}) is part of the Five Precepts (`{{IAST\|Pañcasīla}}`{=mediawiki}), the first of which has been to abstain from killing. This precept of `{{transliteration\|sa\|ahimsa}}`{=mediawiki} is applicable to both the Buddhist layperson and the monastic community. The `{{transliteration\|sa\|ahimsa}}`{=mediawiki} precept is not a commandment, and transgressions did not `{{clarify\|text=invite religious sanctions\|date=July 2023}}`{=mediawiki} for laypersons, but their`{{ambiguous\|date=July 2023}}`{=mediawiki} power has been in the Buddhist belief in karmic consequences and their impact in afterlife during rebirth. Killing, in Buddhist belief, could lead to rebirth in the hellish realm, and for a longer time in more severe conditions if the murder victim was a monk. Saving animals from slaughter for meat is believed to be a way to acquire merit for better rebirth. These moral precepts have been voluntarily self-enforced in lay Buddhist culture through the associated belief in karma and rebirth. Buddhist texts not only recommend `{{transliteration\|sa\|ahimsa}}`{=mediawiki}, but suggest avoiding trading goods that contribute to or are a result of violence: Unlike with lay Buddhists, transgressions by monks do invite sanctions. Full expulsion of a monk from `{{transliteration\|sa\|[[Sangha (Buddhism)\|sangha]]}}`{=mediawiki} follows instances of killing, just like any other serious offense against the monastic `{{transliteration\|pi\|nikaya}}`{=mediawiki} code of conduct. ### War Violent ways of punishing criminals and prisoners of war were not explicitly condemned in Buddhism, but peaceful ways of conflict resolution and punishment with the least amount of injury were encouraged. The early texts condemn the mental states that lead to violent behavior. Nonviolence is an overarching theme within the Pāli Canon. While the early texts condemn killing in the strongest terms, and portray the ideal ruler as a pacifist, such a ruler is nonetheless flanked by an army. It seems that the Buddha\'s teaching on nonviolence was not interpreted or put into practice in an uncompromisingly pacifist or anti-military service way by early Buddhists. The early texts assume war to be a fact of life, and well-skilled soldiers are viewed as necessary for defensive warfare. In Pali texts, injunctions to abstain from violence and involvement with military affairs are directed at members of the `{{transliteration\|sa\|sangha}}`{=mediawiki}; later Mahayana texts, which often generalise monastic norms to laity, require this of lay people as well. The early texts do not contain just-war ideology as such. Some argue that a `{{transliteration\|pi\|[[suttas\|sutta]]}}`{=mediawiki} in the Gamani Samyuttam rules out all military service. In this passage, a soldier asks the Buddha if it is true that, as he has been told, soldiers slain in battle are reborn in a heavenly realm. The Buddha reluctantly replies that if he is killed in battle while his mind is seized with the intention to kill, he will undergo an unpleasant rebirth. In the early texts, a person\'s mental state at the time of death is generally viewed as having a great impact on the next birth. Some Buddhists point to other early texts as justifying defensive war. One example is the Kosala Samyutta, in which King Pasenadi of Kosala, a righteous king favored by the Buddha, learns of an impending attack on his kingdom. He arms himself in defence, and leads his army into battle to protect his kingdom from attack. He lost this battle but won the war. King Pasenadi eventually defeated Emperor Ajātasattu and captured him alive. He thought that, although this King of Magadha has transgressed against his kingdom, he had not transgressed against him personally, and Ajātasattu was still his nephew. He released Ajātasattu and did not harm him. Upon his return, the Buddha said (among other things) that Pasenadi \"is a friend of virtue, acquainted with virtue, intimate with virtue\", while the opposite is said of the aggressor, King Ajātasattu. According to Theravada commentaries, there are five requisite factors that must all be fulfilled for an act to be both an act of killing and to be karmically negative. These are: (1) the presence of a living being, human or animal; (2) the knowledge that the being is a living being; (3) the intent to kill; (4) the act of killing by some means; and (5) the resulting death. Some Buddhists have argued on this basis that the act of killing is complicated, and its ethicality is predicated upon intent. Some have argued that in defensive postures, for example, the primary intention of a soldier is not to kill, but to defend against aggression, and the act of killing in that situation would have minimal negative karmic repercussions. According to Babasaheb Ambedkar, there is circumstantial evidence encouraging `{{transliteration\|sa\|ahimsa}}`{=mediawiki} from the Buddha\'s doctrine, \"Love all, so that you may not wish to kill any.\" Gautama Buddha distinguished between a principle and a rule. He did not make `{{transliteration\|sa\|ahimsa}}`{=mediawiki} a matter of rule, but suggested it as a matter of principle. This gives Buddhists freedom to act. ### Laws Maurya Emperor Ashoka banned animal sacrifice, hunting, slaughter of \"all four-footed creatures that are neither useful nor edible\" and specific animal species, female goats, sheep and pigs nursing their young as well as their young up to the age of six months. Fishing was banned during Chaturmasya and Uposatha. Slave trade in the Maurya Empire was also banned by Ashoka. The emperors of the Sui dynasty, Tang dynasty, and early Song dynasty banned killing in the Lunar calendar\'s 1st, 5th, and 9th months. Empress Wu Tse-Tien banned killing for more than half a year in 692. Some rulers banned fishing for a period of time each year. There were also bans after the death of emperors, after Buddhist and Taoist prayers, and after natural disasters such as Shanghai\'s 1926 summer drought, as well as an eight-day ban beginning August 12, 1959, after the August 7 flood (`{{lang-zh\|c=[[:zh:八七水災\|八七水災]]\|p=Bāqī shuǐzāi}}`{=mediawiki}), the last big flood before the 88 Taiwan Flood. People avoid killing during some festivals, like the Taoist Ghost Festival, the Nine Emperor Gods Festival, and the Vegetarian Festival, as well as during others.	2025-06-20T00:00:00
2,785	Annals of Mathematics	Mathematische Annalen}} `{{Infobox journal \| title = Annals of Mathematics \| cover = \| language = English \| editor = \| discipline = [[Mathematics]] \| abbreviation = Ann. Math. \| mathscinet = Ann. of Math. \| caption = \| formernames = The Analyst \| publisher = [[Princeton University]] and the [[Institute for Advanced Study]] \| country = United States \| frequency = Bimonthly \| history = 1874–present \| openaccess = [[Delayed open-access journal\|Delayed]], after 5 years \| license = \| impact = 5.7 \| impact-year = 2023 \| website = https://annals.math.princeton.edu/ \| link1 = \| link1-name = \| link2 = \| link2-name = \| JSTOR = 0003486X \| OCLC = 01481391 \| LCCN = 49006640 \| CODEN = ANMAAH \| ISSN = 0003-486X \| eISSN = }}`{=mediawiki} The *Annals of Mathematics* is a mathematical journal published every two months by Princeton University and the Institute for Advanced Study. ## History The journal was established as The Analyst in 1874 and with Joel E. Hendricks as the founding editor-in-chief. It was \"intended to afford a medium for the presentation and analysis of any and all questions of interest or importance in pure and applied Mathematics, embracing especially all new and interesting discoveries in theoretical and practical astronomy, mechanical philosophy, and engineering\". It was published in Des Moines, Iowa, and was the earliest American mathematics journal to be published continuously for more than a year or two. This incarnation of the journal ceased publication after its tenth year, in 1883, giving as an explanation Hendricks\' declining health, but Hendricks made arrangements to have it taken over by new management, and it was continued from March 1884 as the Annals of Mathematics. The new incarnation of the journal was edited by Ormond Stone (University of Virginia). It moved to Harvard in 1899 before reaching its current home in Princeton in 1911. An important period for the journal was 1928--1958 with Solomon Lefschetz as editor. Norman Steenrod characterized Lefschetz\' impact as editor as follows: \"The importance to American mathematicians of a first-class journal is that it sets high standards for them to aim at. In this somewhat indirect manner, Lefschetz profoundly affected the development of mathematics in the United States.\" Princeton University continued to publish the Annals on its own until 1933, when the Institute for Advanced Study took joint editorial control. Since 1998, it has been available in an electronic edition, alongside its regular print edition. The electronic edition was available without charge, as an open access journal, but since 2008, this is no longer the case. Issues from before 2003 were transferred to the non-free JSTOR archive, and articles are not freely available until 5 years after publication. ## Abstracting and indexing {#abstracting_and_indexing} The journal is abstracted and indexed in the Science Citation Index, Current Contents/Physical, Chemical & Earth Sciences, and Scopus. According to the Journal Citation Reports, the journal has a 2023 impact factor of 5.7, ranking it third out of 330 journals in the category \"Mathematics\".	2025-06-20T00:00:00
2,802	Akihabara	is a neighborhood in the Chiyoda ward of Tokyo, Japan, generally considered to be the area surrounding Akihabara Station (nicknamed Akihabara Electric Town). This area is part of the `{{nihongo\|Sotokanda\|外神田}}`{=mediawiki} and Kanda-Sakumachō districts of Chiyoda. There is an administrative district called Akihabara (part of Taitō ward), located north of Akihabara Electric Town surrounding Akihabara Neribei Park. The name Akihabara is a shortening of `{{Nihongo\|'''Akibagahara'''\|秋葉ヶ原}}`{=mediawiki}, which comes from `{{nihongo\|'''Akiba'''\|秋葉}}`{=mediawiki}, named after a fire-controlling deity of a firefighting shrine built after the area was destroyed by a fire in 1869. Akihabara gained the nickname `{{nihongo\|'''Akihabara Electric Town'''\|秋葉原電気街\|Akihabara Denki Gai}}`{=mediawiki} shortly after World War II for being a major shopping center for household electronic goods and the post-war black market. Akihabara is considered by many to be the centre of Japanese otaku culture, and is a major shopping district for video games, anime, manga, electronics and computer-related goods. Icons from popular anime and manga are displayed prominently on the shops in the area, and numerous maid cafés and some arcades are found throughout the district. ## Geography The main area of Akihabara is located on a street just west of Akihabara Station. There is an administrative district called Akihabara north of Akihabara Electric Town surrounding Akihabara Neribei Park. This district is part of Taitō ward. ## History Akihabara was once near a city gate of Edo and served as a passage between the city and northwestern Japan. This made the region a home to many craftsmen and tradesmen, as well as some low-class samurai. One of Tokyo\'s frequent fires destroyed the area in 1869, and the people decided to replace the buildings of the area with a shrine called Chinkasha (now known as Akiba Shrine 秋葉神社\]\] `{{Transliteration\|ja\|Akiba Jinja}}`{=mediawiki}, `{{Literally\|fire extinguisher shrine}}`{=mediawiki}), in an attempt to prevent the spread of future fires. The locals nicknamed the shrine Akiba after the deity that could control fire, and the area around it became known as Akibagahara, later Akihabara. After Akihabara Station was built in 1888, the shrine was moved to the Taitō ward, where it resides today. Since its opening in 1890, Akihabara Station became a major freight transit point, which allowed a vegetable and fruit market to spring up. In the 1920s, the station saw a large volume of passengers after opening for public transport. After World War II, the black market thrived in the absence of a strong government. This disconnection of Akihabara from government authority allowed the district to grow as a market city. In the 1950s, this climate turned Akihabara into a market region specializing in household electronics, such as washing machines, refrigerators, televisions, and stereos, earning Akihabara the nickname \"Electric Town\". As household electronics began to lose their futuristic appeal in the 1980s, the shops of Akihabara shifted their focus to home computers, at a time when they were only used by specialists and hobbyists. This brought in a new type of consumer, computer nerds or otaku. The market in Akihabara latched onto their new customer base that was focused on anime, manga, and video games. The connection between Akihabara and otaku has grown to the point that the region is a center for otaku culture. ## Otaku culture {#otaku_culture} The streets of Akihabara are covered with anime and manga icons, and cosplayers line the sidewalks handing out advertisements, especially for maid cafés. Release events, special events, and conventions are common in Akihabara. Architects design the stores of Akihabara to be opaque and closed, to reflect the desire of many otaku to live in their anime worlds rather than display their interests. Akihabara\'s role as a free market has allowed a large amount of amateur work to find an audience. Doujinshi (amateur or fanmade manga) has been growing in Akihabara since the 1970s. ## Transport Akihabara is accessible by train, bus and car. Akihabara Station - Keihin-Tohoku Line (JK-28) - Yamanote Line (JY-03) - Chūō-Sōbu Line (JB-19) - Hibiya Line (H-16) - Tsukuba Express (TX01) Iwamotocho Station - Toei Shinjuku Line (S-08) Suehirocho Station - Ginza Line (G-14)	2025-06-20T00:00:00
2,807	Active Directory	Active Directory (AD) is a directory service developed by Microsoft for Windows domain networks. Windows Server operating systems include it as a set of processes and services.`{{r\|DSA-MSDN\|WI4}}`{=mediawiki} Originally, only centralized domain management used Active Directory. However, it ultimately became an umbrella title for various directory-based identity-related services. A domain controller is a server running the Active Directory Domain Services (AD DS) role. It authenticates and authorizes all users and computers in a Windows domain-type network, assigning and enforcing security policies for all computers and installing or updating software. For example, when a user logs into a computer which is part of a Windows domain, Active Directory checks the submitted username and password and determines whether the user is a system administrator or a non-admin user. Furthermore, it allows the management and storage of information, provides authentication and authorization mechanisms, and establishes a framework to deploy other related services: Certificate Services, Active Directory Federation Services, Lightweight Directory Services, and Rights Management Services. Active Directory uses Lightweight Directory Access Protocol (LDAP) versions 2 and 3, Microsoft\'s version of Kerberos, and DNS. Robert R. King defined it in the following way: ## History Like many information-technology efforts, Active Directory originated out of a democratization of design using Requests for Comments (RFCs). The Internet Engineering Task Force (IETF) oversees the RFC process and has accepted numerous RFCs initiated by widespread participants. For example, LDAP underpins Active Directory. Also, X.500 directories and the Organizational Unit preceded the Active Directory concept that uses those methods. The LDAP concept began to emerge even before the founding of Microsoft in April 1975, with RFCs as early as 1971. RFCs contributing to LDAP include RFC 1823 (on the LDAP API, August 1995), RFC 2307, RFC 3062, and RFC 4533. Microsoft previewed Active Directory in 1999, released it first with Windows 2000 Server edition, and revised it to extend functionality and improve administration in Windows Server 2003. Active Directory support was also added to Windows 95, Windows 98, and Windows NT 4.0 via patch, with some unsupported features. Additional improvements came with subsequent versions of Windows Server. In Windows Server 2008, Microsoft added further services to Active Directory, such as Active Directory Federation Services. The part of the directory in charge of managing domains, which was a core part of the operating system, was renamed Active Directory Domain Services (ADDS) and became a server role like others. \"Active Directory\" became the umbrella title of a broader range of directory-based services. According to Byron Hynes, everything related to identity was brought under Active Directory\'s banner. ## Active Directory Services {#active_directory_services} Active Directory Services consist of multiple directory services. The best known is Active Directory Domain Services, commonly abbreviated as AD DS or simply AD. ### Domain Services {#domain_services} Active Directory Domain Services (AD DS) is the foundation of every Windows domain network. It stores information about domain members, including devices and users, verifies their credentials, and defines their access rights. The server running this service is called a domain controller. A domain controller is contacted when a user logs into a device, accesses another device across the network, or runs a line-of-business Metro-style app sideloaded into a machine. Other Active Directory services (excluding LDS, as described below) and most Microsoft server technologies rely on or use Domain Services; examples include Group Policy, Encrypting File System, BitLocker, Domain Name Services, Remote Desktop Services, Exchange Server, and SharePoint Server. The self-managed Active Directory DS must be distinct from managed Azure AD DS, a cloud product. ### `{{anchor\|ADAM}}`{=mediawiki} Lightweight Directory Services {#lightweight_directory_services} Active Directory Lightweight Directory Services (AD LDS), previously called Active Directory Application Mode (ADAM), implements the LDAP protocol for AD DS. It runs as a service on Windows Server and offers the same functionality as AD DS, including an equal API. However, AD LDS does not require the creation of domains or domain controllers. It provides a Data Store for storing directory data and a Directory Service with an LDAP Directory Service Interface. Unlike AD DS, multiple AD LDS instances can operate on the same server. ### Certificate Services {#certificate_services} Active Directory Certificate Services (AD CS) establishes an on-premises public key infrastructure. It can create, validate, revoke and perform other similar actions, public key certificates for internal uses of an organization. These certificates can be used to encrypt files (when used with Encrypting File System), emails (per S/MIME standard), and network traffic (when used by virtual private networks, Transport Layer Security protocol or IPSec protocol). AD CS predates Windows Server 2008, but its name was simply Certificate Services. AD CS requires an AD DS infrastructure. ### Federation Services {#federation_services} Active Directory Federation Services (AD FS) is a single sign-on service. With an AD FS infrastructure in place, users may use several web-based services (e.g. internet forum, blog, online shopping, webmail) or network resources using only one set of credentials stored at a central location, as opposed to having to be granted a dedicated set of credentials for each service. AD FS uses many popular open standards to pass token credentials such as SAML, OAuth or OpenID Connect. AD FS supports encryption and signing of SAML assertions. AD FS\'s purpose is an extension of that of AD DS: The latter enables users to authenticate with and use the devices that are part of the same network, using one set of credentials. The former enables them to use the same set of credentials in a different network. As the name suggests, AD FS works based on the concept of federated identity. AD FS requires an AD DS infrastructure, although its federation partner may not. ### Rights Management Services {#rights_management_services} Active Directory Rights Management Services (AD RMS), previously known as Rights Management Services or RMS before Windows Server 2008, is server software that allows for information rights management, included with Windows Server. It uses encryption and selective denial to restrict access to various documents, such as corporate e-mails, Microsoft Word documents, and web pages. It also limits the operations authorized users can perform on them, such as viewing, editing, copying, saving, or printing. IT administrators can create pre-set templates for end users for convenience, but end users can still define who can access the content and what actions they can take. ## Logical structure {#logical_structure} Active Directory is a service comprising a database and executable code. It is responsible for managing requests and maintaining the database. The Directory System Agent is the executable part, a set of Windows services and processes that run on Windows 2000 and later. Accessing the objects in Active Directory databases is possible through various interfaces such as LDAP, ADSI, messaging API, and Security Accounts Manager services. ### Objects used {#objects_used} Active Directory structures consist of information about objects classified into two categories: resources (such as printers) and security principals (which include user or computer accounts and groups). Each security principal is assigned a unique security identifier (SID). An object represents a single entity, such as a user, computer, printer, or group, along with its attributes. Some objects may even contain other objects within them. Each object has a unique name, and its definition is a set of characteristics and information by a schema, which determines the storage in the Active Directory. Administrators can extend or modify the schema using the schema object when needed. However, because each schema object is integral to the definition of Active Directory objects, deactivating or changing them can fundamentally alter or disrupt a deployment. Modifying the schema affects the entire system automatically, and new objects cannot be deleted, only deactivated. Changing the schema usually requires planning. ### Forests, trees, and domains {#forests_trees_and_domains} In an Active Directory network, the framework that holds objects has different levels: the forest, tree, and domain. Domains within a deployment contain objects stored in a single replicable database, and the DNS name structure identifies their domains, the namespace. A domain is a logical group of network objects such as computers, users, and devices that share the same Active Directory database. On the other hand, a tree is a collection of domains and domain trees in a contiguous namespace linked in a transitive trust hierarchy. The forest is at the top of the structure, a collection of trees with a standard global catalog, directory schema, logical structure, and directory configuration. The forest is a secure boundary that limits access to users, computers, groups, and other objects. +--------------------------------------------------------------------------------------+-----------------------+ \| \| --- --------------- \| \| \| Domain-Dallas \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| --- --------------- \| +--------------------------------------------------------------------------------------+-----------------------+ \| Example of the geographical organizing of zones of interest within trees and domains \| \| +--------------------------------------------------------------------------------------+-----------------------+ #### Organizational units {#organizational_units} The objects held within a domain can be grouped into organizational units (OUs). OUs can provide hierarchy to a domain, ease its administration, and can resemble the organization\'s structure in managerial or geographical terms. OUs can contain other OUs---domains are containers in this sense. Microsoft recommends using OUs rather than domains for structure and simplifying the implementation of policies and administration. The OU is the recommended level at which to apply group policies, which are Active Directory objects formally named group policy objects (GPOs), although policies can also be applied to domains or sites (see below). The OU is the level at which administrative powers are commonly delegated, but delegation can be performed on individual objects or attributes as well. Organizational units do not each have a separate namespace. As a consequence, for compatibility with Legacy NetBios implementations, user accounts with an identical SamAccountName are not allowed within the same domain even if the accounts objects are in separate OUs. This is because SamAccountName, a user object attribute, must be unique within the domain. However, two users in different OUs can have the same common name (CN), the name under which they are stored in the directory itself such as \"fred.staff-ou.domain\" and \"fred.student-ou.domain\", where \"staff-ou\" and \"student-ou\" are the OUs. In general, the reason for this lack of allowance for duplicate names through hierarchical directory placement is that Microsoft primarily relies on the principles of NetBIOS, which is a flat-namespace method of network object management that, for Microsoft software, goes all the way back to Windows NT 3.1 and MS-DOS LAN Manager. Allowing for duplication of object names in the directory, or completely removing the use of NetBIOS names, would prevent backward compatibility with legacy software and equipment. However, disallowing duplicate object names in this way is a violation of the LDAP RFCs on which Active Directory is supposedly based. As the number of users in a domain increases, conventions such as \"first initial, middle initial, last name\" (Western order) or the reverse (Eastern order) fail for common family names like Li (李), Smith or Garcia. Workarounds include adding a digit to the end of the username. Alternatives include creating a separate ID system of unique employee/student ID numbers to use as account names in place of actual users\' names and allowing users to nominate their preferred word sequence within an acceptable use policy. Because duplicate usernames cannot exist within a domain, account name generation poses a significant challenge for large organizations that cannot be easily subdivided into separate domains, such as students in a public school system or university who must be able to use any computer across the network. ##### Shadow groups {#shadow_groups} In Microsoft\'s Active Directory, OUs do not confer access permissions, and objects placed within OUs are not automatically assigned access privileges based on their containing OU. It represents a design limitation specific to Active Directory, and other competing directories, such as Novell NDS, can set access privileges through object placement within an OU. Active Directory requires a separate step for an administrator to assign an object in an OU as a group member also within that OU. Using only the OU location to determine access permissions is unreliable since the entity might not have been assigned to the group object for that OU yet. A common workaround for an Active Directory administrator is to write a custom PowerShell or Visual Basic script to automatically create and maintain a user group for each OU in their Directory. The scripts run periodically to update the group to match the OU\'s account membership. However, they cannot instantly update the security groups anytime the directory changes, as occurs in competing directories, as security is directly implemented into the Directory. Such groups are known as shadow groups. Once created, these shadow groups are selectable in place of the OU in the administrative tools. Microsoft\'s Server 2008 reference documentation mentions shadow groups but does not provide instructions on creating them. Additionally, there are no available server methods or console snap-ins for managing these groups. An organization must determine the structure of its information infrastructure by dividing it into one or more domains and top-level OUs. This decision is critical and can base on various models such as business units, geographical locations, IT service, object type, or a combination of these models. The immediate purpose of organizing OUs is to simplify administrative delegation and, secondarily, to apply group policies. While OUs serve as an administrative boundary, the forest itself is the only security boundary. All other domains must trust any administrator in the forest to maintain security. ### Partitions The Active Directory database is organized in partitions, each holding specific object types and following a particular replication pattern. Microsoft often refers to these partitions as \'naming contexts. The \'Schema\' partition defines object classes and attributes within the forest. The \'Configuration\' partition contains information on the physical structure and configuration of the forest (such as the site topology). Both replicate all domains in the forest. The \'Domain\' partition holds all objects created in that domain and replicates only within it. ## Physical structure {#physical_structure} Sites are physical (rather than logical) groupings defined by one or more IP subnets. AD also defines connections, distinguishing low-speed (e.g., WAN, VPN) from high-speed (e.g., LAN) links. Site definitions are independent of the domain and OU structure and are shared across the forest. Sites play a crucial role in managing network traffic created by replication and directing clients to their nearest domain controllers (DCs). Microsoft Exchange Server 2007 uses the site topology for mail routing. Administrators can also define policies at the site level. The Active Directory information is physically held on one or more peer domain controllers, replacing the NT PDC/BDC model. Each DC has a copy of the Active Directory. Member servers joined to Active Directory that are not domain controllers are called Member Servers. In the domain partition, a group of objects acts as copies of domain controllers set up as global catalogs. These global catalog servers offer a comprehensive list of all objects in the forest. Global Catalog servers replicate all objects from all domains to themselves, providing an international listing of entities in the forest. However, to minimize replication traffic and keep the GC\'s database small, only selected attributes of each object are replicated, called the partial attribute set (PAS). The PAS can be modified by modifying the schema and marking features for replication to the GC. Earlier versions of Windows used NetBIOS to communicate. Active Directory is fully integrated with DNS and requires TCP/IP---DNS. To fully operate, the DNS server must support SRV resource records, also known as service records. ### Replication Active Directory uses multi-master replication to synchronize changes, meaning replicas pull changes from the server where the change occurred rather than being pushed to them. The Knowledge Consistency Checker (KCC) uses defined sites to manage traffic and create a replication topology of site links. Intra-site replication occurs frequently and automatically due to change notifications, which prompt peers to begin a pull replication cycle. Replication intervals between different sites are usually less consistent and don\'t usually use change notifications. However, it\'s possible to set it up to be the same as replication between locations on the same network if needed. Each DS3, T1, and ISDN link can have a cost, and the KCC alters the site link topology accordingly. Replication may occur transitively through several site links on same-protocol site link bridges if the price is low. However, KCC automatically costs a direct site-to-site link lower than transitive connections. A bridgehead server in each zone can send updates to other DCs in the exact location to replicate changes between sites. To configure replication for Active Directory zones, activate DNS in the domain based on the site. To replicate Active Directory, Remote Procedure Calls (RPC) over IP (RPC/IP) are used. SMTP is used to replicate between sites but only for modifications in the Schema, Configuration, or Partial Attribute Set (Global Catalog) GCs. It\'s not suitable for reproducing the default Domain partition. ## Implementation Generally, a network utilizing Active Directory has more than one licensed Windows server computer. Backup and restore of Active Directory are possible for a network with a single domain controller. However, Microsoft recommends more than one domain controller to provide automatic failover protection of the directory. Domain controllers are ideally single-purpose for directory operations only and should not run any other software or role. Since certain Microsoft products, like SQL Server and Exchange, can interfere with the operation of a domain controller, isolation of these products on additional Windows servers is advised. Combining them can complicate the configuration and troubleshooting of the domain controller or the other installed software more complex. If planning to implement Active Directory, a business should purchase multiple Windows server licenses to have at least two separate domain controllers. Administrators should consider additional domain controllers for performance or redundancy and individual servers for tasks like file storage, Exchange, and SQL Server since this will guarantee that all server roles are adequately supported. One way to lower the physical hardware costs is by using virtualization. However, for proper failover protection, Microsoft recommends not running multiple virtualized domain controllers on the same physical hardware. ## Database The Active-Directory database, the directory store, in Windows 2000 Server uses the JET Blue-based Extensible Storage Engine (ESE98). Each domain controller\'s database is limited to 16 terabytes and 2 billion objects (but only 1 billion security principals). Microsoft has created NTDS databases with more than 2 billion objects. NT4\'s Security Account Manager could support up to 40,000 objects. It has two main tables: the data table and the link table. Windows Server 2003 added a third main table for security descriptor single instancing. Programs may access the features of Active Directory via the COM interfaces provided by Active Directory Service Interfaces. ## Trusting To allow users in one domain to access resources in another, Active Directory uses trusts. Trusts inside a forest are automatically created when domains are created. The forest sets the default boundaries of trust, and implicit, transitive trust is automatic for all domains within a forest. ### Terminology One-way trust : One domain allows access to users on another domain, but the other domain does not allow access to users on the first domain. Two-way trust : Two domains allow access to users on both domains. Trusted domain : The domain that is trusted; whose users have access to the trusting domain. Transitive trust : A trust that can extend beyond two domains to other trusted domains in the forest. Intransitive trust : A one way trust that does not extend beyond two domains. Explicit trust : A trust that an admin creates. It is not transitive and is one way only. Cross-link trust : An explicit trust between domains in different trees or the same tree when a descendant/ancestor (child/parent) relationship does not exist between the two domains. Shortcut : Joins two domains in different trees, transitive, one- or two-way. Forest trust : Applies to the entire forest. Transitive, one- or two-way. Realm : Can be transitive or nontransitive (intransitive), one- or two-way. External : Connect to other forests or non-Active Directory domains. Nontransitive, one- or two-way. PAM trust : A one-way trust used by Microsoft Identity Manager from a (possibly low-level) production forest to a (Windows Server 2016 functionality level) \'bastion\' forest, which issues time-limited group memberships. ## Management tools {#management_tools} Microsoft Active Directory management tools include: - Active Directory Administrative Center (Introduced with Windows Server 2012 and above), - Active Directory Users and Computers, - Active Directory Domains and Trusts, - Active Directory Sites and Services, - ADSI Edit, - Local Users and Groups, - Active Directory Schema snap-ins for Microsoft Management Console (MMC), - SysInternals ADExplorer. These management tools may not provide enough functionality for efficient workflow in large environments. Some third-party tools extend the administration and management capabilities. They provide essential features for a more convenient administration process, such as automation, reports, integration with other services, etc. ## Unix integration {#unix_integration} Varying levels of interoperability with Active Directory can be achieved on most Unix-like operating systems (including Unix, Linux, Mac OS X or Java and Unix-based programs) through standards-compliant LDAP clients, but these systems usually do not interpret many attributes associated with Windows components, such as Group Policy and support for one-way trusts. Third parties offer Active Directory integration for Unix-like platforms, including: - PowerBroker Identity Services, formerly Likewise (BeyondTrust, formerly Likewise Software) -- Allows a non-Windows client to join Active Directory - ADmitMac (Thursby Software Systems) - Samba (free software under GPLv3) -- Can act as a fully functional Active Directory The schema additions shipped with Windows Server 2003 R2 include attributes that map closely enough to RFC 2307 to be generally usable. The reference implementation of RFC 2307, nss_ldap and pam_ldap provided by PADL.com, support these attributes directly. The default schema for group membership complies with RFC 2307bis (proposed). Windows Server 2003 R2 includes a Microsoft Management Console snap-in that creates and edits the attributes. An alternative option is to use another directory service as non-Windows clients authenticate to this while Windows Clients authenticate to Active Directory. Non-Windows clients include 389 Directory Server (formerly Fedora Directory Server, FDS), ViewDS v7.2 XML Enabled Directory, and Sun Microsystems Sun Java System Directory Server. The latter two are both able to perform two-way synchronization with Active Directory and thus provide a \"deflected\" integration. Another option is to use OpenLDAP with its translucent overlay, which can extend entries in any remote LDAP server with additional attributes stored in a local database. Clients pointed at the local database see entries containing both the remote and local attributes, while the remote database remains completely untouched. Administration (querying, modifying, and monitoring) of Active Directory can be achieved via many scripting languages, including PowerShell, VBScript, JScript/JavaScript, Perl, Python, and Ruby. Free and non-free Active Directory administration tools can help to simplify and possibly automate Active Directory management tasks. Since October 2017 Amazon AWS offers integration with Microsoft Active Directory.	2025-06-20T00:00:00
2,810	Aldona of Lithuania	Aldona (baptized Ona or Anna; her pagan name, Aldona, is known only from the writings of Maciej Stryjkowski; c. 1309 -- 26 May 1339) was Queen consort of Poland (1333--1339), and a princess of the Grand Duchy of Lithuania. She was the daughter of Gediminas, Grand Duke of Lithuania. ## Biography Aldona married Casimir III of Poland, when he was 15 or 16 years old. The bride was probably of about the same age. The marriage took place on 30 April or 16 October 1325 and was a purely political maneuver to strengthen the first Polish--Lithuanian coalition against the Teutonic Knights. Casimir was seeking allies in the dispute over Pomerania with the Order. Gediminas had just undertaken an unsuccessful attempt to Christianize Lithuania. This coalition was a prelude to the Union of Krewo in 1385, and the Union of Lublin in 1569, which resulted in the creation of a new state, the Polish--Lithuanian Commonwealth. The details of the agreement are not known; however, it is known that Gediminas released all Polish captives, some 25,000 people, who returned to Poland. The importance of the marriage was attested by the fact that Władysław abandoned his earlier plans to marry his son to Jutta of Bohemia. The alliance was put into effect when joint Polish--Lithuanian forces organized an attack against the Margraviate of Brandenburg in 1326. However, the coalition was not strong and collapsed c. 1330. Yet, there is no evidence of fighting between Poland and Lithuania while Aldona was alive. Aldona died suddenly at the end of May 1339, and was buried in Kraków. Aldona was remembered for her piety and devotion to music. She was accompanied by court musicians wherever she went. It was even suggested by Jan Długosz that the cymbals which were played in procession before her represented a pagan Lithuanian tradition. Her husband Casimir is known for his romantic affairs: after Aldona\'s death he married three more times. ## Issue Aldona had two daughters: - Cunigunde of Poland (died in 1357); married on 1 January 1345 Louis VI the Roman, the son of Louis IV, Holy Roman Emperor. - Elisabeth (1326--1361); married Bogislaus V, Duke of Pomerania. Elisabeth\'s daughter, Elizabeth of Pomerania, was the fourth wife of Charles IV, Holy Roman Emperor. ## In popular culture {#in_popular_culture} ### Film Queen Aldona Anna is one of the main characters in the first season of Polish historical TV drama series \"Korona Królów\" (\"The Crown of the Kings\"). She is played by Marta Bryła.	2025-06-20T00:00:00
2,815	Advanced Mobile Phone System	Advanced Mobile Phone System (AMPS) was an analog mobile phone system standard originally developed by Bell Labs and later modified in a cooperative effort between Bell Labs and Motorola. It was officially introduced in the Americas on October 13, 1983, and was deployed in many other countries too, including Israel in 1986, Australia in 1987, Singapore in 1988, and Pakistan in 1990. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies such as AT&T and Verizon Communications have discontinued this service permanently. AMPS was discontinued in Australia in September 2000, in India by October 2004, in Israel by January 2010, and Brazil by 2010. ## History The first cellular network efforts began at Bell Labs and with research conducted at Motorola. In 1960, John F. Mitchell became Motorola\'s chief engineer for its mobile-communication products, and oversaw the development and marketing of the first pager to use transistors. Motorola had long produced mobile telephones for automobiles, but these large and heavy models consumed too much power to allow their use without the automobile\'s engine running. Mitchell\'s team, which included Dr. Martin Cooper, developed portable cellular telephony. Cooper and Mitchell were among the Motorola employees granted a patent for this work in 1973. The first call on the prototype connected, reportedly, to a wrong number. While Motorola was developing a cellular phone, from 1968 to 1983 Bell Labs worked out a system called Advanced Mobile Phone System (AMPS), which became the first cellular network standard in the United States. The Bell system deployed ASTM in Chicago, Illinois, first as an equipment test serving approximately 100 units in 1978, and subsequently as a service test planned for 2,000 billed units. Motorola and others designed and built the cellular phones for this and other cellular systems. Louis M. Weinberg, a marketing director at AT&T, was named the first president of the AMPS corporation. He served in this position during the startup of the AMPS subsidiary of AT&T. Martin Cooper, a former general manager for the systems division at Motorola, led a team that produced the first cellular handset in 1973 and made the first phone call from it. In 1983 Motorola introduced the DynaTAC 8000x, the first commercially available cellular phone small enough to be easily carried. He later introduced the so-called Bag Phone. In 1992, the first smartphone, called IBM Simon, used AMPS. Frank Canova led its design at IBM and it was demonstrated that year at the COMDEX computer-industry trade-show. A refined version of the product was marketed to consumers in 1994 by BellSouth under the name Simon Personal Communicator. The Simon was the first device that can be properly referred to as a \"smartphone\", even though that term was not yet coined. ## Technology AMPS is a first-generation cellular technology that uses separate frequencies, or \"channels\", for each conversation. It therefore required considerable bandwidth for a large number of users. In general terms, AMPS was very similar to the older \"0G\" Improved Mobile Telephone Service it replaced, but used considerably more computing power to select frequencies, hand off conversations to land lines, and handle billing and call setup. What really separated AMPS from older systems is the \"back end\" call setup functionality. In AMPS, the cell centers could flexibly assign channels to handsets based on signal strength, allowing the same frequency to be re-used, without interference, if locations were separated enough. The channels were grouped so a specific set was different of the one used on the cell nearby. This allowed a larger number of phones to be supported over a geographical area. AMPS pioneers coined the term \"cellular\" because of its use of small hexagonal \"cells\" within a system. AMPS suffered from many weaknesses compared to today\'s digital technologies. As an analog standard, it was susceptible to static and noise, and there was no protection from \'eavesdropping\' using a scanner or an older TV set that could tune into channels 70--83. ## Cloning In the 1990s, an epidemic of \"cloning\" cost the cellular carriers millions of dollars. An eavesdropper with specialized equipment could intercept a handset\'s ESN (Electronic Serial Number) and MDN or CTN (Mobile Directory Number or Cellular Telephone Number). The Electronic Serial Number, a 12-digit number sent by the handset to the cellular system for billing purposes, uniquely identified that phone on the network. The system then allowed or disallowed calls and/or features based on its customer file. A person intercepting an ESN/MDN pair could clone the combination onto a different phone and use it in other areas for making calls without paying. Cellular phone cloning became possible with off-the-shelf technology in the 1990s. Would-be cloners required three key items : 1. A radio receiver, such as the Icom PCR-1000, that could tune into the Reverse Channel (the frequency on which AMPS phones transmit data to the tower) 2. A PC with a sound card and a software program called Banpaia 3. A phone that could easily be used for cloning, such as the Oki 900 The radio, when tuned to the proper frequency, would receive the signal transmitted by the cell phone to be cloned, containing the phone\'s ESN/MDN pair. This signal would feed into the sound-card audio-input of the PC, and Banpaia would decode the ESN/MDN pair from this signal and display it on the screen. The hacker could then copy that data into the Oki 900 phone and reboot it, after which the phone network could not distinguish the Oki from the original phone whose signal had been received. This gave the cloner, through the Oki phone, the ability to use the mobile-phone service of the legitimate subscriber whose phone was cloned -- just as if that phone had been physically stolen, except that the subscriber retained his or her phone, unaware that the phone had been cloned---at least until that subscriber received his or her next bill. The problem became so large that some carriers required the use of a PIN before making calls. Eventually, the cellular companies initiated a system called RF Fingerprinting, whereby it could determine subtle differences in the signal of one phone from another and shut down some cloned phones. Some legitimate customers had problems with this though if they made certain changes to their own phone, such as replacing the battery and/or antenna. The Oki 900 could listen in to AMPS phone-calls right out-of-the-box with no hardware modifications. ## Standards AMPS was originally standardized by American National Standards Institute (ANSI) as EIA/TIA/IS-3. EIA/TIA/IS-3 was superseded by EIA/TIA-553 and TIA interim standard with digital technologies, the cost of wireless service is so low that the problem of cloning has virtually disappeared. ## Frequency bands {#frequency_bands} AMPS cellular service operated in the 850 MHz Cellular band. For each market area, the United States Federal Communications Commission (FCC) allowed two licensees (networks) known as \"A\" and \"B\" carriers. Each carrier within a market used a specified \"block\" of frequencies consisting of 21 control channels and 395 voice channels. Originally, the B (wireline) side license was usually owned by the local phone company, and the A (non-wireline) license was given to wireless telephone providers. At the inception of cellular in 1983, the FCC had granted each carrier within a market 333 channel pairs (666 channels total). By the late 1980s, the cellular industry\'s subscriber base had grown into the millions across America and it became necessary to add channels for additional capacity. In 1989, the FCC granted carriers an expansion from the previous 666 channels to the final 832 (416 pairs per carrier). The additional frequencies were from the band held in reserve for future (inevitable) expansion. These frequencies were immediately adjacent to the existing cellular band. These bands had previously been allocated to UHF TV channels 70--83. Each duplex channel was composed of 2 frequencies. 416 of these were in the 824--849 MHz range for transmissions from mobile stations to the base stations, paired with 416 frequencies in the 869--894 MHz range for transmissions from base stations to the mobile stations. Each cell site used a different subset of these channels than its neighbors to avoid interference. This significantly reduced the number of channels available at each site in real-world systems. Each AMPS channel had a one way bandwidth of 30 kHz, for a total of 60 kHz for each duplex channel. Laws were passed in the US which prohibited the FCC type acceptance and sale of any receiver which could tune the frequency ranges occupied by analog AMPS cellular services.`{{why\|date=August 2023}}`{=mediawiki} Though the service is no longer offered, these laws remain in force (although they may no longer be enforced). ## Narrowband AMPS {#narrowband_amps} In 1991, Motorola proposed an AMPS enhancement known as narrowband AMPS (NAMPS or N-AMPS). ## Digital AMPS {#digital_amps} Later, many AMPS networks were partially converted to D-AMPS, often referred to as TDMA (though TDMA is a generic term that applies to many 2G cellular systems). D-AMPS, commercially deployed since 1993, was a digital, 2G standard used mainly by AT&T Mobility and U.S. Cellular in the United States, Rogers Wireless in Canada, Telcel in Mexico, Telecom Italia Mobile (TIM) in Brazil, VimpelCom in Russia, Movilnet in Venezuela, and Cellcom in Israel. In most areas, D-AMPS is no longer offered and has been replaced by more advanced digital wireless networks. ## Successor technologies {#successor_technologies} AMPS and D-AMPS have now been phased out in favor of either CDMA2000 or GSM, which allow for higher capacity data transfers for services such as WAP, Multimedia Messaging System (MMS), and wireless Internet access. There are some phones capable of supporting AMPS, D-AMPS and GSM all in one phone (using the GAIT standard). ## Analog AMPS being replaced by digital {#analog_amps_being_replaced_by_digital} In 2002, the FCC decided to no longer require A and B carriers to support AMPS service as of February 18, 2008. All AMPS carriers have converted to a digital standard such as CDMA2000 or GSM. Digital technologies such as GSM and CDMA2000 support multiple voice calls on the same channel and offer enhanced features such as two-way text messaging and data services. Unlike in the United States, the Canadian Radio-television and Telecommunications Commission (CRTC) and Industry Canada have not set any requirement for maintaining AMPS service in Canada. Rogers Wireless has dismantled their AMPS (along with IS-136) network; the networks were shut down May 31, 2007. Bell Mobility and Telus Mobility, who operated AMPS networks in Canada, announced that they would observe the same timetable as outlined by the FCC in the United States, and as a result would not begin to dismantle their AMPS networks until after February 2008. OnStar relied heavily on North American AMPS service for its subscribers because, when the system was developed, AMPS offered the most comprehensive wireless coverage in the US. In 2006, ADT asked the FCC to extend the AMPS deadline due to many of their alarm systems still using analog technology to communicate with the control centers. Cellular companies who own an A or B license (such as Verizon and Alltel) were required to provide analog service until February 18, 2008. After that point, however, most cellular companies were eager to shut down AMPS and use the remaining channels for digital services. OnStar transitioned to digital service with the help of data transport technology developed by Airbiquity, but warned customers who could not be upgraded to digital service that their service would permanently expire on January 1, 2008. ## Commercial deployments of AMPS by country {#commercial_deployments_of_amps_by_country} +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Country \| Main Cellular Operator \| Launch date \| End of service \| Notes \| +=========+========================+=============+================+=========================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================+ \| \| \| 1983 \| 2008 \| - Verizon Wireless---Formerly operated an AMPS network. On February 18, 2008, Verizon discontinued all AMPS service. Initially migrated to CDMA2000, but now operates on LTE and 5G. \| \| \| \| \| \| - U.S. Cellular---Formerly operated an AMPS & D-AMPS network. On February 10, 2009, U.S. Cellular discontinued all AMPS & D-AMPS service. Initially migrated to CDMA2000, but now operates on LTE and 5G. \| \| \| \| \| \| - Alltel---In 2005 disclosed that only 15% of their total customer base are still using the existing analog network. The company has posted a three-phase turn down schedule, which was completed in September 2008. With the acquisition of Western Wireless, Alltel now took the claim of the \"largest network in America.\" The claim was true, oddly enough because of wide analog coverage in rural areas. All Alltel AMPS and D-AMPS service was discontinued in September 2008 \| \| \| \| \| \| - Coastel Offshore Cellular---Operated an AMPS network in the Gulf of Mexico that stretched from south of Corpus Christi, TX to south of Gulf Shores, AL. In 2006 Coastel was the only carrier in the US whose entire customer base was still 100% analog based. In 2007 Coastel was merged with Petrocom and SOLA Communications to form Broadpoint Inc. and the network was converted to GSM. \| \| \| \| \| \| - AT&T Mobility -- In areas where AT&T Mobility previously had D-AMPS operating on 1900 MHz frequencies, no analog AMPS network existed, and the D-AMPS network on the 1900 MHz frequency was shut down on July 15, 2007. Service on the remaining 850 MHz AMPS markets was discontinued along with 850 MHz D-AMPS service on February 18, 2008, except in areas where service was provided by Dobson Communications. The Dobson AMPS and TDMA networks were shut down on March 1, 2008. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1984 \| \| - Bell Mobility and Telus Mobility operated AMPS networks in Canada, though they have since been overlaid with digital services. Both Bell Mobility and Telus Mobility had announced that they would observe the same shutdown guidelines as in the United States, and decommissioned their AMPS networks in 2008. \| \| \| \| \| \| - Rogers Wireless---operated an AMPS network in Canada, though it has since been overlaid with digital services. Rogers discontinued its AMPS network on May 31, 2007. \| \| \| \| \| \| - SaskTel -- operated an AMPS network in Saskatchewan, Canada. It was the third-largest AMPS network, by subscribers, in the world at the time of its turndown. It was officially shutdown site by site starting at 00:00 on January 2, 2010, after twenty-one years of service. SaskTel continues to run UMTS networks. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1984 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1984 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1986 \| 2000 \| Telstra (formerly Telecom Australia) -- operated an AMPS network in Australia from February 1987 until the end of 2000. As part of the introduction of mobile phone competition in Australia, the Australian government mandated GSM as the new standard for mobile networks, and required that Telstra close the AMPS network by 2000. However, GSM base stations could only serve a limited area. While this was OK for Europe, it meant that GSM could not cover large, sparsely populated rural areas of Australia cost effectively. Telstra deployed a CDMA network, which did not suffer this limitation, and while the AMPS network was closed down at the end of 1999 in the major cities, the closure deadline was extended until the end of 2000 in rural areas to ease the transition to CDMA. The CDMA network has since been replaced by an 850 MHz UMTS network, Next G. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1986 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1986 \| \| Pelephone -- began offering nationwide AMPS service in Israel in 1986. In the mid-1990s it converted to CDMA (IS-95 and later EV-DO) and in the mid-2000s converted to UMTS. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1991-1992 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1987 \| \| \| 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+---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1987 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1987 \| \| Singtel (previously known as Telecommunications Equipment) -- operated an AMPS network, marketed as a Cellular Mobile Radio System (CMRS), in Singapore from 1988 until 1994. In 1989, Singapore\'s Mass Rapid Transit (MRT) became the first rapid transit system in the world to have full mobile phone coverage inside underground stations and tunnels using AMPS technology. Singtel decommissioned its AMPS network in 1994 after GSM was implemented. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1987 \| 2007 \| Telecom New Zealand (now Spark New Zealand) -- operated an AMPS/TDMA network in New Zealand from 1987 until 2007 throughout the whole country and the network was renowned for its superb coverage, In 2000 Telecom announced that they would discontinue the AMPS network within 5 years (2005) to give customers an opportunity to transition to the CDMA2000 and later 1XRTT technologies that replaced it. They later extended that deadline until 6 pm March 31, 2007. At approximately 7:15 on March 31, 2007, the AMPS/TDMA network ceased to function. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1987 \| \| \| 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+---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1991 \| 2006 \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| 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+---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1989 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| Paktel \| 1990 \| 2004 \| Paktel was granted an AMPS licence in early 1990 to operate a cellular telephone network throughout Pakistan. It was the first company granted a free license to carry out cellular phone services in Pakistan. It carried out AMPS services until 2004, after which it switched to GSM. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1990 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1990 \| 2010 \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1991 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1991 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| Mobikom \| Jan 1994 \| \| Named Mobifon. \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| \| 1994 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \| Uzdunrobita \| 1994 \| \| \| +---------+------------------------+-------------+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+	2025-06-20T00:00:00
2,819	Aerodynamics	300px\\|thumb\\|upright=1.6\\|A NASA wake turbulence study at Wallops Island in 1990. A vortex is created by passage of an aircraft wing, revealed by smoke. Vortices are one of the many phenomena associated with the study of aerodynamics. Aerodynamics (`{{etymology\|grc\|''{{wikt-lang\|grc\|ἀήρ}}'' ({{grc-transl\|ἀήρ}})\|air\|\|''{{wikt-lang\|grc\|δυναμική}}'' ({{grc-transl\|δυναμική}})\|dynamics}}`{=mediawiki}) is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term aerodynamics is often used synonymously with gas dynamics, the difference being that \"gas dynamics\" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature. ## History Modern aerodynamics only dates back to the seventeenth century, but aerodynamic forces have been harnessed by humans for thousands of years in sailboats and windmills, and images and stories of flight appear throughout recorded history, such as the Ancient Greek legend of Icarus and Daedalus. Fundamental concepts of continuum, drag, and pressure gradients appear in the work of Aristotle and Archimedes. In 1726, Sir Isaac Newton became the first person to develop a theory of air resistance, making him one of the first aerodynamicists. Dutch-Swiss mathematician Daniel Bernoulli followed in 1738 with Hydrodynamica in which he described a fundamental relationship between pressure, density, and flow velocity for incompressible flow known today as Bernoulli\'s principle, which provides one method for calculating aerodynamic lift. In 1757, Leonhard Euler published the more general Euler equations which could be applied to both compressible and incompressible flows. The Euler equations were extended to incorporate the effects of viscosity in the first half of the 1800s, resulting in the Navier--Stokes equations. The Navier--Stokes equations are the most general governing equations of fluid flow but are difficult to solve for the flow around all but the simplest of shapes. In 1799, Sir George Cayley became the first person to identify the four aerodynamic forces of flight (weight, lift, drag, and thrust), as well as the relationships between them, and in doing so outlined the path toward achieving heavier-than-air flight for the next century. In 1871, Francis Herbert Wenham constructed the first wind tunnel, allowing precise measurements of aerodynamic forces. Drag theories were developed by Jean le Rond d\'Alembert, Gustav Kirchhoff, and Lord Rayleigh. In 1889, Charles Renard, a French aeronautical engineer, became the first person to reasonably predict the power needed for sustained flight. Otto Lilienthal, the first person to become highly successful with glider flights, was also the first to propose thin, curved airfoils that would produce high lift and low drag. Building on these developments as well as research carried out in their own wind tunnel, the Wright brothers flew the first powered airplane on December 17, 1903. During the time of the first flights, Frederick W. Lanchester, Martin Kutta, and Nikolai Zhukovsky independently created theories that connected circulation of a fluid flow to lift. Kutta and Zhukovsky went on to develop a two-dimensional wing theory. Expanding upon the work of Lanchester, Ludwig Prandtl is credited with developing the mathematics behind thin-airfoil and lifting-line theories as well as work with boundary layers. As aircraft speed increased designers began to encounter challenges associated with air compressibility at speeds near the speed of sound. The differences in airflow under such conditions lead to problems in aircraft control, increased drag due to shock waves, and the threat of structural failure due to aeroelastic flutter. The ratio of the flow speed to the speed of sound was named the Mach number after Ernst Mach who was one of the first to investigate the properties of the supersonic flow. Macquorn Rankine and Pierre Henri Hugoniot independently developed the theory for flow properties before and after a shock wave, while Jakob Ackeret led the initial work of calculating the lift and drag of supersonic airfoils. Theodore von Kármán and Hugh Latimer Dryden introduced the term transonic to describe flow speeds between the critical Mach number and Mach 1 where drag increases rapidly. This rapid increase in drag led aerodynamicists and aviators to disagree on whether supersonic flight was achievable until the sound barrier was broken in 1947 using the Bell X-1 aircraft. By the time the sound barrier was broken, aerodynamicists\' understanding of the subsonic and low supersonic flow had matured. The Cold War prompted the design of an ever-evolving line of high-performance aircraft. Computational fluid dynamics began as an effort to solve for flow properties around complex objects and has rapidly grown to the point where entire aircraft can be designed using computer software, with wind-tunnel tests followed by flight tests to confirm the computer predictions. Understanding of supersonic and hypersonic aerodynamics has matured since the 1960s, and the goals of aerodynamicists have shifted from the behaviour of fluid flow to the engineering of a vehicle such that it interacts predictably with the fluid flow. Designing aircraft for supersonic and hypersonic conditions, as well as the desire to improve the aerodynamic efficiency of current aircraft and propulsion systems, continues to motivate new research in aerodynamics, while work continues to be done on important problems in basic aerodynamic theory related to flow turbulence and the existence and uniqueness of analytical solutions to the Navier--Stokes equations. ## Fundamental concepts {#fundamental_concepts} Understanding the motion of air around an object (often called a flow field) enables the calculation of forces and moments acting on the object. In many aerodynamics problems, the forces of interest are the fundamental forces of flight: lift, drag, thrust, and weight. Of these, lift and drag are aerodynamic forces, i.e. forces due to air flow over a solid body. Calculation of these quantities is often founded upon the assumption that the flow field behaves as a continuum. Continuum flow fields are characterized by properties such as flow velocity, pressure, density, and temperature, which may be functions of position and time. These properties may be directly or indirectly measured in aerodynamics experiments or calculated starting with the equations for conservation of mass, momentum, and energy in air flows. Density, flow velocity, and an additional property, viscosity, are used to classify flow fields. ### Flow classification {#flow_classification} Flow velocity is used to classify flows according to speed regime. Subsonic flows are flow fields in which the air speed field is always below the local speed of sound. Transonic flows include both regions of subsonic flow and regions in which the local flow speed is greater than the local speed of sound. Supersonic flows are defined to be flows in which the flow speed is greater than the speed of sound everywhere. A fourth classification, hypersonic flow, refers to flows where the flow speed is much greater than the speed of sound. Aerodynamicists disagree on the precise definition of hypersonic flow. Compressible flow accounts for varying density within the flow. Subsonic flows are often idealized as incompressible, i.e. the density is assumed to be constant. Transonic and supersonic flows are compressible, and calculations that neglect the changes of density in these flow fields will yield inaccurate results. Viscosity is associated with the frictional forces in a flow. In some flow fields, viscous effects are very small, and approximate solutions may safely neglect viscous effects. These approximations are called inviscid flows. Flows for which viscosity is not neglected are called viscous flows. Finally, aerodynamic problems may also be classified by the flow environment. External aerodynamics is the study of flow around solid objects of various shapes (e.g. around an airplane wing), while internal aerodynamics is the study of flow through passages inside solid objects (e.g. through a jet engine). #### Continuum assumption {#continuum_assumption} Unlike liquids and solids, gases are composed of discrete molecules which occupy only a small fraction of the volume filled by the gas. On a molecular level, flow fields are made up of the collisions of many individual of gas molecules between themselves and with solid surfaces. However, in most aerodynamics applications, the discrete molecular nature of gases is ignored, and the flow field is assumed to behave as a continuum. This assumption allows fluid properties such as density and flow velocity to be defined everywhere within the flow. The validity of the continuum assumption is dependent on the density of the gas and the application in question. For the continuum assumption to be valid, the mean free path length must be much smaller than the length scale of the application in question. For example, many aerodynamics applications deal with aircraft flying in atmospheric conditions, where the mean free path length is on the order of micrometers and where the body is orders of magnitude larger. In these cases, the length scale of the aircraft ranges from a few meters to a few tens of meters, which is much larger than the mean free path length. For such applications, the continuum assumption is reasonable. The continuum assumption is less valid for extremely low-density flows, such as those encountered by vehicles at very high altitudes (e.g. 300,000 ft/90 km) or satellites in Low Earth orbit. In those cases, statistical mechanics is a more accurate method of solving the problem than is continuum aerodynamics. The Knudsen number can be used to guide the choice between statistical mechanics and the continuous formulation of aerodynamics. ### Conservation laws {#conservation_laws} The assumption of a fluid continuum allows problems in aerodynamics to be solved using fluid dynamics conservation laws. Three conservation principles are used: Conservation of mass: Conservation of mass requires that mass is neither created nor destroyed within a flow; the mathematical formulation of this principle is known as the mass continuity equation.\ Conservation of momentum: The mathematical formulation of this principle can be considered an application of Newton\'s second law. Momentum within a flow is only changed by external forces, which may include both surface forces, such as viscous (frictional) forces, and body forces, such as weight. The momentum conservation principle may be expressed as either a vector equation or separated into a set of three scalar equations (x,y,z components).\ Conservation of energy: The energy conservation equation states that energy is neither created nor destroyed within a flow, and that any addition or subtraction of energy to a volume in the flow is caused by heat transfer, or by work into and out of the region of interest. Together, these equations are known as the Navier--Stokes equations, although some authors define the term to only include the momentum equation(s). The Navier--Stokes equations have no known analytical solution and are solved in modern aerodynamics using computational techniques. Because computational methods using high speed computers were not historically available and the high computational cost of solving these complex equations now that they are available, simplifications of the Navier--Stokes equations have been and continue to be employed. The Euler equations are a set of similar conservation equations which neglect viscosity and may be used in cases where the effect of viscosity is expected to be small. Further simplifications lead to Laplace\'s equation and potential flow theory. Additionally, Bernoulli\'s equation is a solution in one dimension to both the momentum and energy conservation equations. The ideal gas law or another such equation of state is often used in conjunction with these equations to form a determined system that allows the solution for the unknown variables. ## Branches of aerodynamics {#branches_of_aerodynamics} Aerodynamic problems are classified by the flow environment or properties of the flow, including flow speed, compressibility, and viscosity. External aerodynamics is the study of flow around solid objects of various shapes. Evaluating the lift and drag on an airplane or the shock waves that form in front of the nose of a rocket are examples of external aerodynamics. Internal aerodynamics is the study of flow through passages in solid objects. For instance, internal aerodynamics encompasses the study of the airflow through a jet engine or through an air conditioning pipe. Aerodynamic problems can also be classified according to whether the flow speed is below, near or above the speed of sound. A problem is called subsonic if all the speeds in the problem are less than the speed of sound, transonic if speeds both below and above the speed of sound are present (normally when the characteristic speed is approximately the speed of sound), supersonic when the characteristic flow speed is greater than the speed of sound, and hypersonic when the flow speed is much greater than the speed of sound. Aerodynamicists disagree over the precise definition of hypersonic flow; a rough definition considers flows with Mach numbers above 5 to be hypersonic. The influence of viscosity on the flow dictates a third classification. Some problems may encounter only very small viscous effects, in which case viscosity can be considered to be negligible. The approximations to these problems are called inviscid flows. Flows for which viscosity cannot be neglected are called viscous flows. ### Incompressible aerodynamics {#incompressible_aerodynamics} An incompressible flow is a flow in which density is constant in both time and space. Although all real fluids are compressible, a flow is often approximated as incompressible if the effect of the density changes cause only small changes to the calculated results. This is more likely to be true when the flow speeds are significantly lower than the speed of sound. Effects of compressibility are more significant at speeds close to or above the speed of sound. The Mach number is used to evaluate whether the incompressibility can be assumed, otherwise the effects of compressibility must be included. #### Subsonic flow {#subsonic_flow} Subsonic (or low-speed) aerodynamics describes fluid motion in flows which are much lower than the speed of sound everywhere in the flow. There are several branches of subsonic flow but one special case arises when the flow is inviscid, incompressible and irrotational. This case is called potential flow and allows the differential equations that describe the flow to be a simplified version of the equations of fluid dynamics, thus making available to the aerodynamicist a range of quick and easy solutions. In solving a subsonic problem, one decision to be made by the aerodynamicist is whether to incorporate the effects of compressibility. Compressibility is a description of the amount of change of density in the flow. When the effects of compressibility on the solution are small, the assumption that density is constant may be made. The problem is then an incompressible low-speed aerodynamics problem. When the density is allowed to vary, the flow is called compressible. In air, compressibility effects are usually ignored when the Mach number in the flow does not exceed 0.3 (about 335 feet (102 m) per second or 228 miles (366 km) per hour at 60 °F (16 °C)). Above Mach 0.3, the problem flow should be described using compressible aerodynamics. ### Compressible aerodynamics {#compressible_aerodynamics} According to the theory of aerodynamics, a flow is considered to be compressible if the density changes along a streamline. This means that -- unlike incompressible flow -- changes in density are considered. In general, this is the case where the Mach number in part or all of the flow exceeds 0.3. The Mach 0.3 value is rather arbitrary, but it is used because gas flows with a Mach number below that value demonstrate changes in density of less than 5%. Furthermore, that maximum 5% density change occurs at the stagnation point (the point on the object where flow speed is zero), while the density changes around the rest of the object will be significantly lower. Transonic, supersonic, and hypersonic flows are all compressible flows. #### Transonic flow {#transonic_flow} The term Transonic refers to a range of flow velocities just below and above the local speed of sound (generally taken as Mach 0.8--1.2). It is defined as the range of speeds between the critical Mach number, when some parts of the airflow over an aircraft become supersonic, and a higher speed, typically near Mach 1.2, when all of the airflow is supersonic. Between these speeds, some of the airflow is supersonic, while some of the airflow is not supersonic. #### Supersonic flow {#supersonic_flow} Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde during cruise can be an example of a supersonic aerodynamic problem. Supersonic flow behaves very differently from subsonic flow. Fluids react to differences in pressure; pressure changes are how a fluid is \"told\" to respond to its environment. Therefore, since sound is, in fact, an infinitesimal pressure difference propagating through a fluid, the speed of sound in that fluid can be considered the fastest speed that \"information\" can travel in the flow. This difference most obviously manifests itself in the case of a fluid striking an object. In front of that object, the fluid builds up a stagnation pressure as impact with the object brings the moving fluid to rest. In fluid traveling at subsonic speed, this pressure disturbance can propagate upstream, changing the flow pattern ahead of the object and giving the impression that the fluid \"knows\" the object is there by seemingly adjusting its movement and is flowing around it. In a supersonic flow, however, the pressure disturbance cannot propagate upstream. Thus, when the fluid finally reaches the object it strikes it and the fluid is forced to change its properties -- temperature, density, pressure, and Mach number---in an extremely violent and irreversible fashion called a shock wave. The presence of shock waves, along with the compressibility effects of high-flow velocity (see Reynolds number) fluids, is the central difference between the supersonic and subsonic aerodynamics regimes. #### Hypersonic flow {#hypersonic_flow} In aerodynamics, hypersonic speeds are speeds that are highly supersonic. In the 1970s, the term generally came to refer to speeds of Mach 5 (5 times the speed of sound) and above. The hypersonic regime is a subset of the supersonic regime. Hypersonic flow is characterized by high temperature flow behind a shock wave, viscous interaction, and chemical dissociation of gas. ## Associated terminology {#associated_terminology} \[\[<File:Types> of flow analysis in fluid mechanics.svg\\|thumb\\|Different types flow analysis around an airfoil: `{{legend\|#f3f3fd\|[[Potential flow]] theory}}`{=mediawiki}\ `{{legend\|#ff9665\|[[Boundary layer\|Boundary layer flow]] theory}}`{=mediawiki}\ `{{legend\|#3b3bde\|[[Turbulence\|Turbulent wake]] analysis}}`{=mediawiki}`]]` The incompressible and compressible flow regimes produce many associated phenomena, such as boundary layers and turbulence. ### Boundary layers {#boundary_layers} The concept of a boundary layer is important in many problems in aerodynamics. The viscosity and fluid friction in the air is approximated as being significant only in this thin layer. This assumption makes the description of such aerodynamics much more tractable mathematically. ### Turbulence In aerodynamics, turbulence is characterized by chaotic property changes in the flow. These include low momentum diffusion, high momentum convection, and rapid variation of pressure and flow velocity in space and time. Flow that is not turbulent is called laminar flow. ## Aerodynamics in other fields {#aerodynamics_in_other_fields} ### Engineering design {#engineering_design} Aerodynamics is a significant element of vehicle design, including road cars and trucks where the main goal is to reduce the vehicle drag coefficient, and racing cars, where in addition to reducing drag the goal is also to increase the overall level of downforce. Aerodynamics is also important in the prediction of forces and moments acting on sailing vessels. It is used in the design of mechanical components such as hard drive heads. Structural engineers resort to aerodynamics, and particularly aeroelasticity, when calculating wind loads in the design of large buildings, bridges, and wind turbines. The aerodynamics of internal passages is important in heating/ventilation, gas piping, and in automotive engines where detailed flow patterns strongly affect the performance of the engine. ### Environmental design {#environmental_design} Urban aerodynamics are studied by town planners and designers seeking to improve amenity in outdoor spaces, or in creating urban microclimates to reduce the effects of urban pollution. The field of environmental aerodynamics describes ways in which atmospheric circulation and flight mechanics affect ecosystems. Aerodynamic equations are used in numerical weather prediction. ### Ball-control in sports {#ball_control_in_sports} Sports in which aerodynamics are of crucial importance include soccer, table tennis, cricket, baseball, and golf, in which most players can control the trajectory of the ball using the \"Magnus effect\".	2025-06-20T00:00:00
2,820	Andreas Schlüter	Andreas Schlüter (1659 -- c. June 1714) was a German baroque sculptor and architect, active in the Holy Roman Empire, the Polish--Lithuanian Commonwealth, and Russia. ## Biography Andreas Schlüter was born probably in Hamburg, in 1659. His early life is obscure as at least three different persons of that name are documented. The records of St. Michaelis Church, Hamburg show that an Andreas Schlüter, son of sculptor Gerhart Schlüter, had been baptized there on 22 May 1664. Documents from Gdańsk reported that an Andreas Schlüter (senior) had worked 1640--1652 in Gdańsk\'s Jopengasse lane (today\'s ulica Piwna). Possibly born in 1640, an Andres Schliter is recorded as apprentice on 9 May 1656 by the mason\'s guild. Other sources state 1659 as year of birth. He probably did spend several years abroad as Journeyman. His first work, in 1675, may have been epitaphs of the Dukes Sambor and Mestwin in the dome of Pelplin monastery. Schlüter\'s first known work was the decoration of the facade of the Gdańsk Royal Chapel, in 1681. He later created statues for King John III Sobieski\'s Wilanów Palace in Warsaw and sepulchral sculptures in Zhovkva. In 1689, he moved to Warsaw and made the pediment reliefs and sculptural work of Krasiński Palace. Schlüter was invited to Berlin in 1694 by Eberhard von Danckelmann to work as court sculptor at the armory (Zeughaus) for Elector Frederick III. His sculpted decorations are a masterpiece of baroque expression and pathos. While the more visible reliefs on the outside had to praise fighting, the statues of dying warriors in the interior denounced war and gave an indication of his pacifist religious beliefs (he is said to have been a Mennonite). Travelling through Italy in 1696, he studied the work of masters like Michelangelo Buonarroti and Gian Lorenzo Bernini. Schlüter also worked as an architect and built many state buildings in Berlin in his role as \"Hofbaumeister\" (Court Architect), which he lost when one tower showed signs of a weak fundament. He also served as director of the Prussian Academy of Arts from 1702 to 1704, after which he began concentrating on sculpting again, as \"Hofbildhauer\" (Court Sculptor). His most important equestrian sculpture is that of the \"Great Elector\", Frederick William of Brandenburg, cast in 1708 and placed at \"Lange Brücke\" near the Berlin City Palace, now situated in the honor court before Charlottenburg Palace. The Berlin City Palace, and many of his works, were partially destroyed by bombing in World War II and by the subsequent Communist regime. A similar fate probably befell the Amber Room, made between 1701 and 1709, Schlüter\'s most famous work of architecture. The Berlin City Palace was reconstructed between 2013 and 2020. In 1713, Schlüter\'s fame brought him to work for Tsar Peter I of Russia in Saint Petersburg, where he died of an illness after creating several designs. Together with Johann Friedrich Braunstein, he designed the Grand Palace and Monplaisir Palace in Peterhof Palace Complex. Also the city\'s oldest building, Kikin Hall, and the reliefs at the Summer Palace are attributed to him. This way he became an important figure of Petrine Baroque. ## Extant works {#extant_works} - Facade of the Royal Chapel, Gdańsk, 1681 - Sculptures on the facade of Wilanów Palace, Warsaw, after 1681 - Sculptures on the pediment of Krasiński Palace, Warsaw, 1682--83, 1689--1693 - Epitaph of Adam Zygmunt Konarski, St. Mary\'s Cathedral of the Assumption, Frombork near Gdańsk, after 1683 - Altar and crucifix in church, Węgrów near Warsaw, 1688--1690 - Altar in Czerniaków church, Warsaw, 1690 - Portrait bishop Jan Małachowski in Wawel Cathedral, Kraków 1693 - Aepulchral sculptures of the Sobieski family, Zhovkva near Lviv, 1692--93 - Equestrian statue of Elector Frederick William, courtyard of Charlottenburg Palace, Berlin, 1689--1703, with a copy in the Berlin Bode-Museum - Sculptures on the facade of the Zeughaus in Berlin, 1695--1706 - Berlin City Palace, 1699--1706 - Amber Room (reconstruction) in the Catherine Palace of Tsarskoye Selo near Saint Petersburg, 1701 - Pulpit, St. Mary\'s Church, Berlin, 1703 - Sarcophagi of Friedrich I and Sophia Charlotte, King and Queen in Prussia in the Berlin Cathedral	2025-06-20T00:00:00
2,826	Antigonid dynasty	Roman Macedonia \\| flag_s1 = \\| s2 = Seleucid Empire \\| flag_s2 = \\| image_s2 = \\| s3 = \\| flag_s3 = \\| image_s3 = \\| image_coat = Perseus of Macedonia Tetradrachm 90060057.jpg \\| coa_size = 175px \\| symbol = \\| symbol_type = Tetradrachm with the Eagle of Zeus and the inscription ΒΑΣΙΛΕΩΣ ΠΕΡΣΕΩΣ, \"\[coin\] of King Perseus\" \\| stat_year1 = 301 BC \\| stat_area1 = \\| stat_year2 = \\| stat_area2 = \\| stat_year3 = \\| stat_area3 = \\| stat_year4 = \\| stat_area4 = \\| image_map = Macedonia and the Aegean World c.200.png \\| image_map_caption = Antigonid Empire c. 200 BC \\| capital = Antigonia (Antigonus I)\ Demetrias (Demetrius I)\ Pella (since Antigonus II) \\| common_languages = Greek \\| religion = Ancient Greek / Hellenistic \\| leader1 = Antigonus I Monophthalmus \\| leader2 = Perseus of Macedon \\| year_leader1 = 306 BC -- 301 BC \\| year_leader2 = 179 BC -- 168 BC \\| title_leader = Basileus }} The Antigonid dynasty (`{{IPAc-en\|æ\|n\|ˈ\|t\|ɪ\|ɡ\|oʊ-\|n\|ɪ\|d}}`{=mediawiki}; Ἀντιγονίδαι) was a Macedonian Greek royal house which ruled the kingdom of Macedon during the Hellenistic period. Founded by Antigonus I Monophthalmus, a general and successor of Alexander the Great, the dynasty first came to power after the Battle of Salamis in 306 BC and ruled much of Hellenistic Greece from 294 until their defeat at the Battle of Pydna in 168 BC (Third Macedonian War), after which Macedon came under the control of the Roman Republic. The wars of the Diadochi witnessed the fall of the Argead dynasty in Macedon resulting in a power vacuum, which the Antigonid and Antipatrid dynasties sought to occupy. The Antigonid family first rose to power when Demetrius I Poliorcetes, son of Antigonus I, ousted Cassander\'s governor of Athens in 306 BC giving his father control over a land spanning from the Aegean Sea to the Middle East. Despite the subsequent instability and loss of the Asian territory, the family managed to maintain its power in mainland Greece and the islands, with Antigonus II Gonatas ultimately solidifying Antigonid rule over Hellenistic Macedon --a territory also known as the Antigonid Empire. Antigonus III Doson further expanded Macedonian influence in southern Greece reestablishing the Hellenic Alliance with himself as the president. Under Philip V, Antigonid Macedon first came into conflict with Rome, which had become a decisive power in the eastern Mediterranean. In the second century BC, the last Antigonid king, Perseus, became known as the champion of Greek resistance against Rome, albeit Rome\'s control over Antigonid Greece began to steadily expand, culminating in the fall of the dynasty in 168. ## History The beginning of Hellenistic Greece was defined by the struggle between the Antipatrid dynasty, led first by Cassander (r. 305 -- 297 BC), son of Antipater, and the Antigonid dynasty, led by Antigonus I Monophthalmus (r. 306 -- 301 BC) and his son, the future king Demetrius I Poliorcetes (r. 294 -- 288 BC). After the power crisis in Macedon, which culminated in Philip III\'s and Euridice\'s death, Cassander managed to seize control from Olympias and began to establish his authority in the kingdom; in 316 BC he buried Philip III and Euridice at Aegae and married Philip II\'s daughter, Thessalonica, thus becoming a member of the Argead dynasty. In 310/309 BC, Cassander commanded Glaucias to secretly assassinate the 14-year-old Alexander IV, son of Alexander the Great, and his mother Roxane and the Macedonian Argead dynasty became extinct. In 307 BC, Demetrius I successfully ousted Cassander\'s governor of Athens, Demetrius of Phalerum, and after defeating Ptolemy I at the Battle of Salamis in 306 BC he conquered the island Cyprus. Following that victory, Demetrius\' father, Antigonus I, assumed the title of Basileus (\"King\" of Alexander\'s Empire) by the assembled armies and gained control over the Aegean, the eastern Mediterranean, and most of the Middle East. While Antigonus and Demetrius attempted to recreate Philip II\'s Hellenic league with themselves as dual hegemons, a revived coalition of Cassander, Ptolemy I Soter, Seleucus I Nicator, and Lysimachus decisively defeated the Antigonids at the Battle of Ipsus in 301 BC, during which Antigonus I was killed. Demetrius I survived the battle and in 294 BC --during the struggles between Casander\'s sons Alexander V and Antipater I-- he managed to seize control of Athens and establish himself as king of Macedon. In 288 BC, he was driven out by Pyrrhus and Lysimachus and eventually died as a prisoner of Seleucus I Nicator. After a long period of instability, Demetrius\' son Antigonus II Gonatas was able to establish the family\'s control over the old Kingdom of Macedon, as well as over most of the Greek city-states by 276 BC. ## Legacy The Antigonid was one of four dynasties established by Alexander\'s successors, the others being the Seleucid dynasty, Ptolemaic dynasty and Antipatrid dynasty. The last scion of the dynasty, Perseus of Macedon, who reigned between 179 and 168 BC, proved unable to stop the advancing Roman legions and Macedon\'s defeat at the Battle of Pydna signaled the end of the dynasty. ## Dynasty The ruling members of the Antigonid dynasty were: +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| King \| Reign (BC) \| Consort(s) \| \\|Comments \| +=============================================================+:=====================================:+=========================+===============================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================+ \| Antigonus I Monophthalmus (Western Asian Antigonid kingdom) \| 306--301 BC \| Stratonice \| One of Alexander the Great\'s top generals; a major participant in the so-called \"funeral games\" following that king\'s death. \| \| \| \| \| \| \| \| \| \| \"Monophthalmus\" is Greek for \"One-eyed,\" a reference to a disfiguring battle scar. \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Demetrius I Poliorcetes (Macedon, Cicilia) \| 294--287 BC \| Phila\ \| Son of Antigonus I Monophthalmus. Demetrius\' wife Phila was a daughter of Antipater, and ancestor of all subsequent Antigonid kings of Macedon, except Antigonus III Doson, through her son Antigonus II Gonatas. Antigonus III Doson was descended from the marriage of Demetrius and Ptolemais, who was a daughter of Ptolemy I Soter and mother of Doson\'s father, Demetrius the Fair, the ephemeral King of Cyrene. Deïdameia was a daughter of Aeacides of Epirus and sister of Pyrrhus, she had one son, Alexander, by Demetrius. Demetrius had a further two sons, Demetrius the Thin and Corrhagus, the former by an unnamed Illyrian woman, the latter by a woman named Eurydice. Demetrius I Poliorcetes was the first Antigonid king of Macedon. \| \| \| \| Ptolemais\ \| \| \| \| \| Deïdameia\ \| \| \| \| \| Lanassa\ \| \| \| \| \| ?Eurydice\ \| \| \| \| \| ?Unnamed Illyrian woman \| \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Antigonus II Gonatas (Macedon) \| 276--239 BC \| Phila \| Son of Demetrius Poliorcetes and Phila, grandson of Antigonus I Monophthalmus. His wife, Phila, was the daughter of his sister, Stratonice. Only one known legitimate child, Demetrius II Aetolicus. \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Demetrius the Fair (Cyrene) \| c\. 250 BC \| Olympias of Larissa\ \| Son of Demetrius I Poliorcetes and Ptolemaïs. Father of Antigonus III Doson and, apparently, Echecrates by Olympias. \| \| \| \| Berenice II \| \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Demetrius II Aetolicus (Macedon) \| 239--229 BC \| Stratonice of Macedon\ \| Son of Antigonus II and Phila. Stratonice of Macedon was a daughter of Antiochus I Soter and Stratonice. Phthia of Epirus was a daughter of Alexander II of Epirus and Olympias II of Epirus. Nicaea of Corinth was the widow of Demetrius\' cousin, Alexander of Corinth. Chryseis was a former captive of Demetrius. Only known son, Philip by Chryseis, also had a daughter by Stratonice of Macedon, Apama III. \| \| \| \| Phthia of Epirus\ \| \| \| \| \| Nicaea of Corinth\ \| \| \| \| \| Chryseis \| \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Antigonus III Doson (Macedon) \| 229--221 BC \| Chryseis \| Son of Demetrius the Fair and Olympias of Larissa. Children unknown. \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \ \| 221--179 BC \| Polycratia of Argos \| Son of Demetrius II and Chryseis. At least four children: Perseus of Macedon, Apame, Demetrius and Philippus. \| \| Philip V (Macedon) \| \| \| \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| \ \| 179--168 BC\ \| Laodice V \| The last ruler of Macedon. Laodice V was a daughter of the Seleucid king, Seleucus IV Philopator. At least two sons, Philip and Alexander. \| \| Perseus (Macedon) \| `{{small\|(died 166 BC)}}`{=mediawiki} \| \| \| +-------------------------------------------------------------+---------------------------------------+-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ : Antigonid rulers The Greek rebel against Rome and last King of Macedonia, Andriscus, claimed to be the son of Perseus. ## Family tree of Antigonids {#family_tree_of_antigonids} ## Coin gallery {#coin_gallery} -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Antigone le Borgne (pièce).jpg\\|Coin of Antigonus I Monophthalmus (\"the One-eyed\") (382--301 BC). Démétrios Ier Poliorcète (pièce).jpg\\|Coin of Demetrius I of Macedon (\"The Besieger\"), (337--283 BC), son of Antigonus I Monophthalmus Tetradrachm of Antigonus Doson.jpg\\|Coin of Antigonus II Gonatas Philip VI Andriskos.jpg\\|Coin of Philip VI Andriscus. Greek inscription reads ΒΑΣΙΛΕΩΣ ΦΙΛΙΠΠΟΥ (King Philip). -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- : style=\"background-color:#f8eaba; text-align:center\"\\| Antigonid dynasty coins	2025-06-20T00:00:00
2,830	Abjuration	Abjuration is the solemn repudiation, abandonment, or renunciation by or upon oath, often the renunciation of citizenship or some other right or privilege. The term comes from the Latin abjurare, \"to forswear\". ## Abjuration of the realm {#abjuration_of_the_realm} Abjuration of the realm was a type of abjuration in ancient English law. The person taking the oath swore to leave the country directly and promptly, never to return to the kingdom unless by permission of the sovereign. This was often taken by fugitives who had taken sanctuary: ## English Commonwealth {#english_commonwealth} Near the start of the English Civil War, on 18 August 1643 Parliament passed \"An Ordinance for Explanation of a former Ordinance for Sequestration of Delinquents Estates with some Enlargements.\" The enlargements included an oath which became known as the \"Oath of Abjuration\": `{{Blockquote\|I ..; Do abjure and renounce the [[Papal supremacy\|Pope's Supremacy]] and Authority over the Catholic Church in General, and over my self in Particular; And I do believe that there is not any [[Transubstantiation]] in the Sacrament of the Lords Supper, or in the Elements of [[Sacramental bread\|Bread]] and [[Sacramental wine\|Wine]] after Consecration thereof, by any Person whatsoever; And I do also believe, that there is not any [[Purgatory]], Or that the consecrated [[Sacramental bread\|Host]], Crucifixes, or Images, ought to be worshipped, or that any worship is due unto any of them; And I also believe that [[Salvation]] cannot be Merited by Works, and all Doctrines in affirmation of the said Points; I do abjure and renounce, without any Equivocation, Mental Reservation, or secret Evasion whatsoever, taking the words by me spoken, according to the common and usual meaning of them. So help me God.<ref>C.H. Firth, R.S. Rait (editors (1911)). ''Acts and Ordinances of the Interregnum, 1642-1660'', "August 1643: An Ordinance for Explanation of a former Ordinance for Sequestration of Delinquents Estates with some Enlargements", [http://www.british-history.ac.uk/report.aspx?compid=55851 pp. 254-260]. Date accessed: 16 March 2010</ref>}}`{=mediawiki} In 1656--7, it was reissued in what was for Catholics an even more objectionable form. Everyone was to be \"adjudged a Papist\" who refused this oath, and the consequent penalties began with the confiscation of two-thirds of the recusant\'s goods, and went on to deprive him of almost every civic right. The Catholic Encyclopaedia makes the point that the oath and the penalties were so severe that it stopped the efforts of the Gallicanizing party among the English Catholics, who had been ready to offer forms of submission similar to the old oath of Allegiance, which was condemned anew about this time by Pope Innocent X. ## Scotland During The Killing Time of the 1680s an Abjuration Oath could be put to suspects where they were given the option to abjure or renounce their allegiances. The terms of the oath were deliberately designed to offend the consciences of the Presbyterian Covenanters. Those who would not swear \"whether they have arms, or not\" could be \"immediately killed\" by field trial \"before two witnesses\" on a charge of high treason. John Brown was included among those executed in this judicial process by John Graham (Bluidy Clavers) on 1 May 1685. The wives and children of such men could also be put out of their houses if they had spoken to the suspect or refused the oath themselves. ## Great Britain and Ireland {#great_britain_and_ireland} In England (and after 1707 Great Britain) the Oath of Abjuration denied the royal title of James II\'s heirs (i.e. the direct Catholic descendant of the House of Stuart exiled after the Glorious Revolution in 1688). In England, an Oath of Abjuration was taken by Members of Parliament, clergy, and laymen, pledging to support the current British monarch and repudiated the right of the Stuarts and other claimants to the throne. This oath was imposed under William III, George I and George III. It was superseded by the oath of allegiance. In Ireland, the oath was imposed of state officeholders, teachers, lawyers, and on the clergy of the established church in from 1703, the following year it was on all Irish voters and from 1709 it could be demanded of any adult male by a magistrate. ## Bilino Polje abjuration {#bilino_polje_abjuration} The Bilino Polje abjuration, also known as \"Confessio Christianorum bosniensis\", was an act of alleged heresy abjuration by clergy of the Bosnian Church in presence of the Bosnian ruler, Ban Kulin, and Giovanni da Casamari. It affirmed the primacy of the pope and related to errors of practice, stemming from ignorance, rather than heretical doctrines. It was signed by seven Bosnian priors, on 8 April 1203 at Bilino Polje field, near today town of Zenica, in Bosnia and Herzegovina. The same document was brought to Buda, in 30 April by Giovanni da Casamari, Ban Kulin and two abbots, where it was examined by Emeric, King of Hungary, and the high clergy. ## The Netherlands {#the_netherlands} Another famous abjuration was brought about by the Plakkaat van Verlatinghe of July 26, 1581, the formal Act of Abjuration or declaration of independence of the Low Countries from the Spanish king, Philip II. This oath was the climax of the Eighty Years\' War (Dutch Revolt).	2025-06-20T00:00:00
2,834	A Vindication of the Rights of Woman	*A Vindication of the Rights of Woman: with Strictures on Political and Moral Subjects* , is a 1792 feminist essay written by British philosopher and women\'s rights advocate Mary Wollstonecraft (1759--1797), and is one of the earliest works of feminist philosophy. In it, Wollstonecraft responds to those educational and political theorists of the eighteenth century who did not believe women should receive a rational education. She argues that women ought to have an education commensurate with their position in society, claiming that women are essential to the nation because they educate its children and because they could be \"companions\" to their husbands, rather than mere wives. Instead of viewing women as ornaments to society or property to be traded in marriage, Wollstonecraft maintains that they are human beings deserving of the same fundamental rights as men. Wollstonecraft was prompted to write the Rights of Woman after reading Charles Maurice de Talleyrand-Périgord\'s 1791 report to the French National Assembly, which stated that women should only receive domestic education. From her reaction to this specific event, she launched a broad attack against double standards, indicting men for encouraging women to indulge in excessive emotion. Wollstonecraft hurried to complete the work in direct response to ongoing events; she intended to write a more thoughtful second volume but died before completing it. While Wollstonecraft does call for equality between the sexes in particular areas of life, especially morality, she does not explicitly state that men and women are equal. Her ambiguous statements regarding the equality of the sexes have made it difficult to classify Wollstonecraft as a modern feminist; the word itself did not emerge until decades after her death. Although it is commonly assumed that the Rights of Woman was unfavourably received, this is a modern misconception based on the belief that Wollstonecraft was as reviled during her lifetime as she became after the publication of William Godwin\'s Memoirs of the Author of A Vindication of the Rights of Woman (1798). The Rights of Woman was generally received well when it was first published in 1792. Biographer Emily W. Sunstein called it \"perhaps the most original book of \[Wollstonecraft\'s\] century\". Wollstonecraft\'s work had a significant impact on advocates for women\'s rights in the nineteenth century, particularly the 1848 Seneca Falls Convention which produced the Declaration of Sentiments laying out the aims of the women\'s suffrage movement in the United States. ## Historical context {#historical_context} A Vindication of the Rights of Woman was written against the tumultuous background of the French Revolution and the debates that it spawned in Britain. In a lively and sometimes vicious pamphlet war, now referred to as the Revolution controversy, British political commentators addressed topics ranging from representative government to human rights to the separation of church and state, many of these issues having been raised in France first. Wollstonecraft first entered this fray in 1790 with A Vindication of the Rights of Men, a response to Edmund Burke\'s Reflections on the Revolution in France (1790). In his Reflections, Burke criticized the view of many British thinkers and writers who had welcomed the early stages of the French revolution. While they saw the revolution as analogous to Britain\'s own Glorious Revolution in 1688, which had restricted the powers of the monarchy, Burke argued that the appropriate historical analogy was the English Civil War (1642--1651) in which Charles`{{spaces}}`{=mediawiki}I had been executed in 1649. He viewed the French revolution as the violent overthrow of a legitimate government. In Reflections he argues that citizens do not have the right to revolt against their government because civilization is the result of social and political consensus; its traditions cannot be continually challenged`{{snd}}`{=mediawiki}the result would be anarchy. One of the key arguments of Wollstonecraft\'s Rights of Men, published just six weeks after Burke\'s Reflections, is that rights cannot be based on tradition; rights, she argues, should be conferred because they are reasonable and just, regardless of their basis in tradition. When Charles Maurice de Talleyrand-Périgord presented his Rapport sur l\'instruction publique (1791) to the National Assembly in France, Wollstonecraft was galvanized to respond. In his recommendations for a national system of education, Talleyrand had written: > Let us bring up women, not to aspire to advantages which the Constitution denies them, but to know and appreciate those which it guarantees them`{{spaces}}`{=mediawiki}\... Men are destined to live on the stage of the world. A public education suits them: it early places before their eyes all the scenes of life: only the proportions are different. The paternal home is better for the education of women; they have less need to learn to deal with the interests of others, than to accustom themselves to a calm and secluded life. Wollstonecraft dedicated the Rights of Woman to Talleyrand: \"Having read with great pleasure a pamphlet which you have lately published, I dedicate this volume to you; to induce you to reconsider the subject, and maturely weigh what I have advanced respecting the rights of woman and national education.\" At the end of 1791, French feminist Olympe de Gouges had published her Declaration of the Rights of Woman and of the Female Citizen, and the question of women\'s rights became central to political debates in both France and Britain. The Rights of Woman is an extension of Wollstonecraft\'s arguments in the Rights of Men. In the Rights of Men, as the title suggests, she is concerned with the rights of particular men (eighteenth-century British men) while in the Rights of Woman, she is concerned with the rights afforded to \"woman\", an abstract category. She does not isolate her argument to eighteenth-century women or British women. The first chapter of the Rights of Woman addresses the issue of natural rights and asks who has those inalienable rights and on what grounds. She answers that since natural rights are given by God, for one segment of society to deny them to another segment is a sin. The Rights of Woman thus engages not only specific events in France and in Britain but also larger questions being raised by political philosophers such as John Locke and Jean-Jacques Rousseau. ## Themes The Rights of Woman is a long (almost 87,000 words) essay that introduces all of its major topics in the opening chapters and then repeatedly returns to them, each time from a different point of view. It also adopts a hybrid tone that combines rational argument with the fervent rhetoric of sensibility. Wollstonecraft did not employ the formal argumentation or logical prose style common to eighteenth-century philosophical writing. Hysteria was once seen as a physical phenomenon`{{snd}}`{=mediawiki}physicians and anatomists believed that the more \"sensitive\" people\'s \"nerves\", the more emotionally affected they would be by their surroundings. Since women were thought to have keener nerves than men, it was believed that women were more emotional than men. The emotional excess associated with sensibility also theoretically produced an ethic of compassion: those with sensibility could easily sympathise with people in pain. Thus historians have credited the discourse of sensibility and those who promoted it with the increased humanitarian efforts, such as the movement to abolish the slave trade. But sensibility also paralysed those who had too much of it; as scholar G. J. Barker-Benfield explains, \"an innate refinement of nerves was also identifiable with greater suffering, with weakness, and a susceptibility to disorder\". By the time Wollstonecraft was writing the Rights of Woman, sensibility had already been under sustained attack for a number of years. Sensibility, which had initially promised to draw individuals together through sympathy, was now viewed as \"profoundly separatist\"; novels, plays, and poems that employed the language of sensibility asserted individual rights, sexual freedom, and unconventional familial relationships based only upon feeling. Furthermore, as Janet Todd, another scholar of sensibility, argues, \"to many in Britain the cult of sensibility seemed to have feminized the nation, given women undue prominence, and emasculated men\". ### Rational education {#rational_education} One of Wollstonecraft\'s central arguments in the Rights of Woman is that women should be educated in a rational manner to give them the opportunity to contribute to society. In the eighteenth century, it was often assumed by educational philosophers and conduct book writers, who wrote what one might think of as early self-help books, that women were incapable of rational or abstract thought. Women, it was believed, were too susceptible to sensibility and too fragile to be able to think clearly. Wollstonecraft, along with other female reformers such as Catharine Macaulay and Hester Chapone, maintained that women were indeed capable of rational thought and deserved to be educated. She argued this point in her own conduct book, Thoughts on the Education of Daughters (1787), in her children\'s book, Original Stories from Real Life (1788), as well as in the Rights of Woman. Stating in her preface that \"my main argument is built on this simple principle, that if \[woman\] be not prepared by education to become the companion of man, she will stop the progress of knowledge and virtue; for truth must be common to all\", Wollstonecraft contends that society will degenerate without educated women, particularly because mothers are the primary educators of young children. She attributes the problem of uneducated women to men and \"a false system of education, gathered from the books written on this subject by men who \[consider\] females rather as women than human creatures\". Women are capable of rationality; it only appears that they are not, because men have refused to educate them and encouraged them to be frivolous (Wollstonecraft describes silly women as \"spaniels\" and \"toys\"). Wollstonecraft attacks conduct book writers such as James Fordyce and John Gregory as well as educational philosophers such as Jean-Jacques Rousseau who argue that a woman does not need a rational education. (Rousseau argues in Emile \[1762\] that women should be educated for the pleasure of men; Wollstonecraft, infuriated by this argument, attacks not only it but also Rousseau himself.) Intent on illustrating the limitations that contemporary educational theory placed upon women, Wollstonecraft writes, \"taught from their infancy that beauty is woman\'s sceptre, the mind shapes itself to the body, and, roaming round its gilt cage, only seeks to adorn its prison\", implying that without this damaging ideology, which encourages young women to focus their attention on beauty and outward accomplishments, they could achieve much more. Wives could be the rational \"companions\" of their husbands and even pursue careers should they so choose: \"women might certainly study the art of healing, and be physicians as well as nurses. And midwifery, decency seems to allot to them`{{spaces}}`{=mediawiki}\... they might, also, study politics`{{spaces}}`{=mediawiki}\... Business of various kinds, they might likewise pursue.\" For Wollstonecraft, \"the most perfect education\" is \"an exercise of the understanding as is best calculated to strengthen the body and form the heart. Or, in other words, to enable the individual to attach such habits of virtue as will render it independent.\" In addition to her broad philosophical arguments, Wollstonecraft lays out a specific plan for national education to counter Talleyrand\'s. In Chapter 12, \"On National Education\", she proposes that children be sent to free day schools as well as given some education at home \"to inspire a love of home and domestic pleasures\". She also maintains that schooling should be co-educational, contending that men and women, whose marriages are \"the cement of society\", should be \"educated after the same model\". ### Feminism It is debatable to what extent the Rights of Woman is a feminist text; because the definitions of feminist vary, different scholars have come to different conclusions. The words feminist and feminism were not coined until the 1890s, and there was no feminist movement to speak of during Wollstonecraft\'s lifetime. Rights of Woman is often considered the source or original, \"the ur-document of modern liberal feminism\". In the introduction to her work on Wollstonecraft\'s thought, Barbara Taylor writes: > Describing \[Wollstonecraft\'s philosophy\] as feminist is problematic, and I do it only after much consideration. The label is of course anachronistic`{{spaces}}`{=mediawiki}\... Treating Wollstonecraft\'s thought as an anticipation of nineteenth and twentieth-century feminist argument has meant sacrificing or distorting some of its key elements. Leading examples of this`{{spaces}}`{=mediawiki}\... have been the widespread neglect of her religious beliefs, and the misrepresentation of her as a bourgeois liberal, which together have resulted in the displacement of a religiously inspired utopian radicalism by a secular, class-partisan reformism as alien to Wollstonecraft\'s political project as her dream of a divinely promised age of universal happiness is to our own. Even more important however has been the imposition on Wollstonecraft of a heroic-individualist brand of politics utterly at odds with her own ethically driven case for women\'s emancipation. Wollstonecraft\'s leading ambition for women was that they should attain virtue, and it was to this end that she sought their liberation. In the Rights of Woman, Wollstonecraft does not make the claim for gender equality using the same arguments or the same language that late nineteenth- and twentieth-century feminists later would. For instance, rather than unequivocally stating that men and women are equal, Wollstonecraft contends that men and women are equal in the eyes of God, which means that they are both subject to the same moral law. For Wollstonecraft, men and women are equal in the most important areas of life. While such an idea may not seem revolutionary to twenty-first-century readers, its implications were revolutionary during the eighteenth century. For example, it implied that both men and women`{{snd}}`{=mediawiki}not just women`{{snd}}`{=mediawiki}should be modest and respect the sanctity of marriage. Wollstonecraft\'s argument exposed the sexual double standard of the late eighteenth century and demanded that men adhere to the same virtues demanded of women. However, Wollstonecraft\'s arguments for equality stand in contrast to her statements respecting the superiority of masculine strength and valour. Wollstonecraft states: > Let it not be concluded, that I wish to invert the order of things; I have already granted, that, from the constitution of their bodies, men seem to be designed by Providence to attain a greater degree of virtue. I speak collectively of the whole sex; but I see not the shadow of a reason to conclude that their virtues should differ in respect to their nature. In fact, how can they, if virtue has only one eternal standard? I must therefore, if I reason consequentially, as strenuously maintain that they have the same simple direction, as that there is a God. Wollstonecraft calls on men, rather than women, to initiate the social and political changes she outlines in the Rights of Woman. Because women are uneducated, they cannot alter their own situation`{{snd}}`{=mediawiki}men must come to their aid. Wollstonecraft writes at the end of her chapter \"Of the Pernicious Effects Which Arise from the Unnatural Distinctions Established in Society\": > I then would fain convince reasonable men of the importance of some of my remarks; and prevail on them to weigh dispassionately the whole tenor of my observations`{{spaces}}`{=mediawiki}\... I appeal to their understandings; and, as a fellow-creature, claim, in the name of my sex, some interest in their hearts. I entreat them to assist to emancipate their companion, to make her a help meet for them! Would men but generously snap our chains, and be content with rational fellowship instead of slavish obedience, they would find us more observant daughters, more affectionate sisters, more faithful wives, more reasonable mothers`{{snd}}`{=mediawiki}in a word, better citizens. Wollstonecraft\'s last novel, Maria: or, The Wrongs of Woman (1798), the fictionalized sequel to the Rights of Woman, is usually considered her most radical feminist work. ### Sensibility One of Wollstonecraft\'s most scathing criticisms in the Rights of Woman is against false and excessive sensibility, particularly in women. She argues that women who succumb to sensibility are \"blown about by every momentary gust of feeling\"; because these women are \"the prey of their senses\", they cannot think rationally. Not only do they do harm to themselves but they also do harm to all of civilization: these are not women who can refine civilization`{{snd}}`{=mediawiki}these are women who will destroy it. But reason and feeling are not independent for Wollstonecraft; rather, she believes that they should inform each other. For Wollstonecraft the passions underpin all reason. This was a theme that she would return to throughout her career, but particularly in her novels Mary: A Fiction (1788) and Maria: or, The Wrongs of Woman. For the eighteenth-century Scottish philosopher David Hume, reason is dominated by the passions. He held that passions rather than reason govern human behaviour, famously proclaiming in A Treatise of Human Nature that \"Reason is, and ought only to be the slave of the passions\". As part of her argument that women should not be overly influenced by their feelings and emotions, Wollstonecraft emphasises that they should not be constrained by or made slaves to their bodies or their sexual feelings. This particular argument has led many modern feminists to suggest that Wollstonecraft intentionally avoids granting women any sexual desire. Cora Kaplan argues that the \"negative and prescriptive assault on female sexuality\" is a leitmotif of the Rights of Woman. For example, Wollstonecraft advises her readers to \"calmly let passion subside into friendship\" in the ideal companionate marriage (that is, in the ideal of a love-based marriage that was developing at the time). It would be better, she writes, when \"two virtuous young people marry . . . if some circumstances checked their passion\". According to Wollstonecraft, \"love and friendship cannot subsist in the same bosom\". As Mary Poovey explains, \"Wollstonecraft betrays her fear that female desire might in fact court man\'s lascivious and degrading attentions, that the subordinate position women have been given might even be deserved. Until women can transcend their fleshly desires and fleshly forms, they will be hostage to the body.\" If women are not interested in sexuality, they cannot be dominated by men. Wollstonecraft worries that women are consumed with \"romantic wavering\", that is, they are interested only in satisfying their lusts. Because the Rights of Woman eliminates sexuality from a woman\'s life, Kaplan contends, it \"expresses a violent antagonism to the sexual\" while at the same time \"exaggerat\[ing\] the importance of the sensual in the everyday life of women\". Wollstonecraft was so determined to wipe sexuality from her picture of the ideal woman that she ended up foregrounding it by insisting upon its absence. But as Kaplan and others have remarked, Wollstonecraft may have been forced to make this sacrifice: \"it is important to remember that the notion of woman as politically enabled and independent \[was\] fatally linked \[during the eighteenth century\] to the unrestrained and vicious exercise of her sexuality.\" ### Republicanism Claudia Johnson, a prominent Wollstonecraft scholar, has called the Rights of Woman \"a republican manifesto\". Johnson contends that Wollstonecraft is hearkening back to the Commonwealth tradition of the seventeenth century and attempting to reestablish a republican ethos. In Wollstonecraft\'s version, there would be strong, but separate, masculine and feminine roles for citizens. According to Johnson, Wollstonecraft \"denounces the collapse of proper sexual distinction as the leading feature of her age, and as the grievous consequence of sentimentality itself. The problem undermining society in her view is feminized men\". If men feel free to adopt both the masculine position and the sentimental feminine position, she argues, women have no position open to them in society. Johnson therefore sees Wollstonecraft as a critic, in both the Rights of Men and the Rights of Woman, of the \"masculinization of sensitivity\" in such works as Edmund Burke\'s Reflections on the Revolution in France. In the Rights of Woman Wollstonecraft adheres to a version of republicanism that includes a belief in the eventual overthrow of all titles, including the monarchy. She also suggests that all men and women should be represented in government. But the bulk of her \"political criticism\", as Chris Jones, a Wollstonecraft scholar, explains, \"is couched predominantly in terms of morality\". Her definition of virtue focuses on the individual\'s happiness rather than, for example, the good of society. This is reflected in her explanation of natural rights. Because rights ultimately proceed from God, Wollstonecraft maintains that there are duties, tied to those rights, incumbent upon each and every person. For Wollstonecraft, the individual is taught republicanism and benevolence within the family; domestic relations and familial ties are crucial to her understanding of social cohesion and patriotism. ### Class In many ways the Rights of Woman is inflected by a bourgeois view of the world, as is its direct predecessor the Rights of Men. Wollstonecraft addresses her text to the middle class, which she calls the \"most natural state\". She also frequently praises modesty and industry, virtues which, at the time, were associated with the middle class. From her position as a middle-class writer arguing for a middle-class ethos, Wollstonecraft also attacks the wealthy, criticizing them using the same arguments she employs against women. She points out the \"false-refinement, immorality, and vanity\" of the rich, calling them \"weak, artificial beings, raised above the common wants and affections of their race, in a premature unnatural manner \[who\] undermine the very foundation of virtue, and spread corruption through the whole mass of society\". But Wollstonecraft\'s criticisms of the wealthy do not necessarily reflect a concomitant sympathy for the poor. For her, the poor are fortunate because they will never be trapped by the snares of wealth: \"Happy is it when people have the cares of life to struggle with; for these struggles prevent their becoming a prey to enervating vices, merely from idleness!\" She contends that charity has only negative consequences because, as Jones puts it, she \"sees it as sustaining an unequal society while giving the appearance of virtue to the rich\". In her national plan for education, she retains class distinctions (with an exception for the intelligent), suggesting that: \"After the age of nine, girls and boys, intended for domestic employments, or mechanical trades, ought to be removed to other schools, and receive instruction, in some measure appropriated to the destination of each individual`{{spaces}}`{=mediawiki}\... The young people of superior abilities, or fortune, might now be taught, in another school, the dead and living languages, the elements of science, and continue the study of history and politics, on a more extensive scale, which would not exclude polite literature.\" ## Rhetoric and style {#rhetoric_and_style} In attempting to navigate the cultural expectations of female writers and the generic conventions of political and philosophical discourse, Wollstonecraft, as she does throughout her oeuvre, constructs a unique blend of masculine and feminine styles in the Rights of Woman. She uses the language of philosophy, referring to her work as a \"treatise\" with \"arguments\" and \"principles\". However, Wollstonecraft also uses a personal tone, employing \"I\" and \"you\", dashes and exclamation marks, and autobiographical references to create a distinctly feminine voice in the text. The Rights of Woman further hybridizes its genre by weaving together elements of the conduct book, the short essay, and the novel, genres often associated with women, while at the same time claiming that these genres could be used to discuss philosophical topics such as rights. Although Wollstonecraft argues against excessive sensibility, the rhetoric of the Rights of Woman is at times heated and attempts to provoke the reader. Many of the most emotional comments in the book are directed at Rousseau. For example, after excerpting a long passage from Emile (1762), Wollstonecraft pithily states, \"I shall make no other comments on this ingenious passage, than just to observe, that it is the philosophy of lasciviousness.\" A mere page later, after indicting Rousseau\'s plan for female education, she writes \"I must relieve myself by drawing another picture.\" These terse exclamations are meant to draw the reader to her side of the argument (it is assumed that the reader will agree with them). While she claims to write in a plain style so that her ideas will reach the broadest possible audience, she actually combines the plain, rational language of the political treatise with the poetic, passionate language of sensibility to demonstrate that one can combine rationality and sensibility in the same self. In her efforts to vividly describe the condition of women within society, Wollstonecraft employs several different analogies. She often compares women to slaves, arguing that their ignorance and powerlessness places them in that position. But at the same time, she also compares them to \"capricious tyrants\" who use cunning and deceit to manipulate the men around them. At one point, she reasons that a woman can become either a slave or tyrant, which she describes as two sides of the same coin. Wollstonecraft also compares women to soldiers; like military men, they are valued only for their appearance and obedience. And like the rich, women\'s \"softness\" has \"debased mankind\". ## Revision Wollstonecraft was forced to write the Rights of Woman hurriedly to respond to Talleyrand and ongoing events. Upon completing the work, she wrote to her friend William Roscoe: \"I am dissatisfied with myself for not having done justice to the subject`{{spaces}}`{=mediawiki}\... Do not suspect me of false modesty`{{snd}}`{=mediawiki}I mean to say that had I allowed myself more time I could have written a better book, in every sense of the word`{{spaces}}`{=mediawiki}\... I intend to finish the next volume before I begin to print, for it is not pleasant to have the Devil coming for the conclusion of a sheet fore it is written.\" When Wollstonecraft revised the Rights of Woman for the second edition, she took the opportunity not only to fix small spelling and grammar mistakes but also to bolster the feminist claims of her argument. She changed some of her statements regarding female and male difference to reflect a greater equality between the sexes. Wollstonecraft never wrote the second part to the Rights of Woman, although William Godwin published her \"Hints\", which were \"chiefly designed to have been incorporated in the second part of the Vindication of the Rights of Woman\", in the posthumous collection of her works. However, she did begin writing the novel Maria: or, The Wrongs of Woman, which most scholars consider a fictionalized sequel to the Rights of Woman. It was unfinished at her death and also included in the Posthumous Works published by Godwin. ## Reception and legacy {#reception_and_legacy} When it was first published in 1792, the Rights of Woman was reviewed favourably by the Analytical Review, the General Magazine, the Literary Magazine, New York Magazine, and the Monthly Review, although the assumption persists that Rights of Woman received hostile reviews. It was almost immediately released in a second edition in 1792, several American editions appeared, and it was translated into French. Taylor writes that \"it was an immediate success\". Moreover, other writers such as Mary Hays and Mary Robinson specifically alluded to Wollstonecraft\'s text in their own works. Hays cited the Rights of Woman in her novel Memoirs of Emma Courtney (1796) and modelled her female characters after Wollstonecraft\'s ideal woman. Although female conservatives such as Hannah More excoriated Wollstonecraft personally, they actually shared many of the same values. As the scholar Anne Mellor has shown, both More and Wollstonecraft wanted a society founded on \"Christian virtues of rational benevolence, honesty, personal virtue, the fulfillment of social duty, thrift, sobriety, and hard work\". During the early 1790s, many writers within British society were engaged in an intense debate regarding the position of women in society. For example, the respected poet and essayist Anna Laetitia Barbauld and Wollstonecraft sparred back and forth; Barbauld published several poems responding to Wollstonecraft\'s work and Wollstonecraft commented on them in footnotes to the Rights of Woman. The work also provoked outright hostility. The bluestocking Elizabeth Carter was unimpressed with the work. Thomas Taylor, the Neoplatonist translator who had been a landlord to the Wollstonecraft family in the late 1770s, swiftly wrote a satire called A Vindication of the Rights of Brutes: if women have rights, why not animals too? After Wollstonecraft died in 1797, her husband William Godwin published his Memoirs of the Author of A Vindication of the Rights of Woman (1798). He revealed much about her private life that had previously not been known to the public: her illegitimate child, her love affairs, and her attempts at suicide. While Godwin believed he was portraying his wife with love, sincerity, and compassion, contemporary readers were shocked by Wollstonecraft\'s unorthodox lifestyle and she became a reviled figure. Richard Polwhele targeted her in particular in his anonymous long poem The Unsex\'d Females (1798), a defensive reaction to women\'s literary self-assertion: Hannah More is Christ to Wollstonecraft\'s Satan. His poem was \"well known\" among the responses to A Vindication. Wollstonecraft\'s ideas became associated with her life story and women writers felt that it was dangerous to mention her in their texts. Hays, who had previously been a close friend and an outspoken advocate for Wollstonecraft and her Rights of Woman, for example, did not include her in the collection of Illustrious and Celebrated Women she published in 1803. Maria Edgeworth specifically distances herself from Wollstonecraft in her novel Belinda (1802); she caricatures Wollstonecraft as a radical feminist in the character of Harriet Freke. But, like Jane Austen, she does not reject Wollstonecraft\'s ideas. Both Edgeworth and Austen argue that women are crucial to the development of the nation; moreover, they portray women as rational beings who should choose companionate marriage. The negative views towards Wollstonecraft persisted for over a century. The Rights of Woman was not reprinted until the middle of the nineteenth century and it still retained an aura of ill-repute. George Eliot wrote \"there is in some quarters a vague prejudice against the Rights of Woman as in some way or other a reprehensible book, but readers who go to it with this impression will be surprised to find it eminently serious, severely moral, and withal rather heavy\". The suffragist (i.e. moderate reformer, as opposed to suffragette) Millicent Garrett Fawcett wrote the introduction to the centenary edition of the Rights of Woman, cleansing the memory of Wollstonecraft and claiming her as the foremother of the struggle for the vote. While the Rights of Woman may have paved the way for feminist arguments, twentieth-century feminists have tended to use Wollstonecraft\'s life story, rather than her texts, for inspiration; her unorthodox lifestyle convinced them to try new \"experiments in living\", as Virginia Woolf termed it in her famous essay on Wollstonecraft. However, there is some evidence that the Rights of Woman may be influencing current feminists. Ayaan Hirsi Ali, a feminist who is critical of Islam\'s dictates regarding women, cites the Rights of Woman in her autobiography Infidel, writing that she was \"inspired by Mary Wollstonecraft, the pioneering feminist thinker who told women they had the same ability to reason as men did and deserved the same rights\". Miriam Schneir also includes this text in her anthology Feminism: The Essential Historical Writings, labelling it as one of the essential feminist works. Further evidence of the enduring legacy of Wollstonecraft\'s A Vindication may be seen by direct references in recent historical fiction set: for example, in The Silk Weaver (1998) set in the late eighteenth century among Dublin silk weavers, author Gabrielle Warnock (1998) intervenes as narrator to hold up 'Rights of Woman' for the reader to reflect upon the politics, morals, and feelings of her female characters. In Death Comes to Pemberley (2011), set in 1803, P. D. James has one male character reference Rights of Woman in reproving another (Darcy) for denying voice to the woman in matters that concern her.	2025-06-20T00:00:00
2,836	Azawakh	The Azawakh is a breed of dog from West Africa. With ancient origins, it is raised throughout the Sahelian zone of Mali, Niger, and Burkina Faso. This region includes the Azawagh Valley for which the breed is named. While commonly associated with the nomadic Tuareg people, the dogs are also bred and owned by other ethnic groups, such as the Peulh, Bella, and Hausa. The Azawakh is more related to the Sloughi than it is to the Saluki.`{{unreliable source?\|reason=Author did her own analysis\|date=April 2019}}`{=mediawiki} ## Description ### Appearance Slim and elegant, with bone structure and muscles showing through thin skin. Eyes are almond-shaped. The coat is very short and almost absent on the belly. Its bone structure shows clearly through the skin and musculature. Its muscles are \"dry\", meaning that they are quite flat, unlike the Greyhound and Whippet. In this respect it is similar in type to the Saluki. ### Colours Colours permitted by the Fédération Cynologique Internationale (FCI) breed standard are clear sand to dark fawn/brown, red and brindle (with or without a dark mask), with white bib, tail tip, and white on all feet (which can be tips of toes to high stockings). Since 2015 white stockings that go above the elbow joint are considered disqualifying features in the FCI member countries, as is a white collar or half collar (Irish marked). Some conservationists support the idea that in Africa, Azawakhs are still found in a variety of colours such as red, blue fawn (that is, with a lilac cast), grizzle, and, rarely, blue and black with various white markings including Irish marked (white collar) and particolour (mostly white). Because of this wide color variation in the native population, the American standard used by the AKC and UKC allows any color combination found in Africa. ### Movement The Azawakh\'s light, supple, lissome gait is a notable breed characteristic, as is an upright double suspension gallop. ## Temperament Bred by the Tuareg, Fula and various other nomads of the Sahara and sub-Saharan Sahel in the countries of Mali, Niger, Burkina Faso, and southern Algeria, the breed known by the Tuaregs as "Oska" was used there as a guard dog and to hunt gazelle and hare at speeds up to 40 mph. The austerity of the Sahel environment has ensured that only the most fit dogs survive and has accentuated the breed\'s ruggedness and independence. Unlike some other sighthounds, the Azawakh is more of a pack hunter and they bump down the quarry with hindquarters when it has been tired out. In role of a guard dog, if an Azawakh senses danger it will bark to alert the other members of the pack, and they will gather together as a pack under the lead of the alpha dog, then chase off or attack the predator. Unlike other sighthounds, the primary function of the Azawakh in its native land is that of a guard dog. It develops an intense bond with its owner, and tend to be reserved with strangers. Azawakh have high energy and tremendous endurance. They are excellent training companions for runners. Many Azawakh dislike rain and cold weather. Azawakh are pack oriented and form complex social hierarchies. They have tremendous memories and are able to recognize each other after long periods of separation. They can often be found sleeping on top of each other for warmth and companionship. ## Breed history {#breed_history} The breed is relatively uncommon in Europe and North America but there is a growing band of devotees. Azawakh may be registered with the FCI in the USA via the Federación Canófila de Puerto Rico (FCPR). European FCI clubs and the AKC recognize the FCPR as an acceptable registry. The AKC recognized the Azawakh a member of the Hound group in 2019. The American Azawakh Association (AAA) is the AKC Parent Club for the Azawakh. Azawakh may be registered with the UKC and ARBA. The breed is not yet registered by CKC. Azawakh are eligible for ASFA and AKC lure coursing and NOFCA open field coursing events.	2025-06-20T00:00:00
2,839	Angular momentum	Angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity -- the total angular momentum of a closed system remains constant. Angular momentum has both a direction and a magnitude, and both are conserved. Bicycles and motorcycles, flying discs, rifled bullets, and gyroscopes owe their useful properties to conservation of angular momentum. Conservation of angular momentum is also why hurricanes form spirals and neutron stars have high rotational rates. In general, conservation limits the possible motion of a system, but it does not uniquely determine it. The three-dimensional angular momentum for a point particle is classically represented as a pseudovector `{{math\|'''r''' × '''p'''}}`{=mediawiki}, the cross product of the particle\'s position vector `{{math\|'''r'''}}`{=mediawiki} (relative to some origin) and its momentum vector; the latter is `{{math\|1='''p''' = ''m'''''v'''}}`{=mediawiki} in Newtonian mechanics. Unlike linear momentum, angular momentum depends on where this origin is chosen, since the particle\'s position is measured from it. Angular momentum is an extensive quantity; that is, the total angular momentum of any composite system is the sum of the angular momenta of its constituent parts. For a continuous rigid body or a fluid, the total angular momentum is the volume integral of angular momentum density (angular momentum per unit volume in the limit as volume shrinks to zero) over the entire body. Similar to conservation of linear momentum, where it is conserved if there is no external force, angular momentum is conserved if there is no external torque. Torque can be defined as the rate of change of angular momentum, analogous to force. The net external torque on any system is always equal to the total torque on the system; the sum of all internal torques of any system is always 0 (this is the rotational analogue of Newton\'s third law of motion). Therefore, for a closed system (where there is no net external torque), the total torque on the system must be 0, which means that the total angular momentum of the system is constant. The change in angular momentum for a particular interaction is called angular impulse, sometimes twirl. Angular impulse is the angular analog of (linear) impulse. ## Examples The trivial case of the angular momentum $L$ of a body in an orbit is given by $L = 2 \pi M f r^2$ where $M$ is the mass of the orbiting object, $f$ is the orbit\'s frequency and $r$ is the orbit\'s radius. The angular momentum $L$ of a uniform rigid sphere rotating around its axis, instead, is given by $L = \frac{4}{5} \pi M f r^2$ where $M$ is the sphere\'s mass, $f$ is the frequency of rotation and $r$ is the sphere\'s radius. Thus, for example, the orbital angular momentum of the Earth with respect to the Sun is about 2.66 × 10^40^ kg⋅m^2^⋅s^−1^, while its rotational angular momentum is about 7.05 × 10^33^ kg⋅m^2^⋅s^−1^. In the case of a uniform rigid sphere rotating around its axis, if, instead of its mass, its density is known, the angular momentum $L$ is given by $L = \frac{16}{15} \pi^2 \rho f r^5$ where $\rho$ is the sphere\'s density, $f$ is the frequency of rotation and $r$ is the sphere\'s radius. In the simplest case of a spinning disk, the angular momentum $L$ is given by $L = \pi M f r^2$ where $M$ is the disk\'s mass, $f$ is the frequency of rotation and $r$ is the disk\'s radius. If instead the disk rotates about its diameter (e.g. coin toss), its angular momentum $L$ is given by $L = \frac{1}{2} \pi M f r^2$ ## Definition in classical mechanics {#definition_in_classical_mechanics} Just as for angular velocity, there are two special types of angular momentum of an object: the spin angular momentum is the angular momentum about the object\'s center of mass, while the orbital angular momentum is the angular momentum about a chosen center of rotation. The Earth has an orbital angular momentum by nature of revolving around the Sun, and a spin angular momentum by nature of its daily rotation around the polar axis. The total angular momentum is the sum of the spin and orbital angular momenta. In the case of the Earth the primary conserved quantity is the total angular momentum of the Solar System because angular momentum is exchanged to a small but important extent among the planets and the Sun. The orbital angular momentum vector of a point particle is always parallel and directly proportional to its orbital angular velocity vector ω, where the constant of proportionality depends on both the mass of the particle and its distance from origin. The spin angular momentum vector of a rigid body is proportional but not always parallel to the spin angular velocity vector Ω, making the constant of proportionality a second-rank tensor rather than a scalar. ### Orbital angular momentum in two dimensions {#orbital_angular_momentum_in_two_dimensions} Angular momentum is a vector quantity (more precisely, a pseudovector) that represents the product of a body\'s rotational inertia and rotational velocity (in radians/sec) about a particular axis. However, if the particle\'s trajectory lies in a single plane, it is sufficient to discard the vector nature of angular momentum, and treat it as a scalar (more precisely, a pseudoscalar). Angular momentum can be considered a rotational analog of linear momentum. Thus, where linear momentum `{{mvar\|p}}`{=mediawiki} is proportional to mass `{{mvar\|m}}`{=mediawiki} and linear speed `{{nowrap\|{{mvar\|v}},}}`{=mediawiki} $p = mv,$ angular momentum `{{mvar\|L}}`{=mediawiki} is proportional to moment of inertia `{{mvar\|I}}`{=mediawiki} and angular speed `{{mvar\|ω}}`{=mediawiki} measured in radians per second. $L = I\omega.$ Unlike mass, which depends only on amount of matter, moment of inertia depends also on the position of the axis of rotation and the distribution of the matter. Unlike linear velocity, which does not depend upon the choice of origin, orbital angular velocity is always measured with respect to a fixed origin. Therefore, strictly speaking, `{{mvar\|L}}`{=mediawiki} should be referred to as the angular momentum relative to that center. In the case of circular motion of a single particle, we can use $I = r^2m$ and $\omega = {v}/{r}$ to expand angular momentum as $L = r^2 m \cdot {v}/{r},$ reducing to: $L = rmv,$ the product of the radius of rotation `{{mvar\|r}}`{=mediawiki} and the linear momentum of the particle $p = mv$, where $v= r\omega$ is the linear (tangential) speed. This simple analysis can also apply to non-circular motion if one uses the component of the motion perpendicular to the radius vector: $L = rmv_\perp,$ where $v_\perp = v\sin(\theta)$ is the perpendicular component of the motion. Expanding, $L = rmv\sin(\theta),$ rearranging, $L = r\sin(\theta)mv,$ and reducing, angular momentum can also be expressed, $L = r_\perp mv,$ where $r_\perp = r\sin(\theta)$ is the length of the moment arm, a line dropped perpendicularly from the origin onto the path of the particle. It is this definition, `{{math\|(length of moment arm) × (linear momentum)}}`{=mediawiki}, to which the term moment of momentum refers. ### Scalar angular momentum from Lagrangian mechanics {#scalar_angular_momentum_from_lagrangian_mechanics} Another approach is to define angular momentum as the conjugate momentum (also called canonical momentum) of the angular coordinate $\phi$ expressed in the Lagrangian of the mechanical system. Consider a mechanical system with a mass $m$ constrained to move in a circle of radius $r$ in the absence of any external force field. The kinetic energy of the system is $T = \tfrac{1}{2}mr^2 \omega^2 = \tfrac{1}{2}mr^2 \dot{\phi}^2.$ And the potential energy is $U = 0.$ Then the Lagrangian is $\mathcal{L}\left(\phi, \dot{\phi}\right) = T - U = \tfrac{1}{2}mr^2 \dot{\phi}^2.$ The generalized momentum \"canonically conjugate to\" the coordinate $\phi$ is defined by $p_\phi = \frac{\partial \mathcal{L}}{\partial \dot{\phi}} = mr^2 \dot{\phi} = I\omega = L.$ ### Orbital angular momentum in three dimensions {#orbital_angular_momentum_in_three_dimensions} To completely define orbital angular momentum in three dimensions, it is required to know the rate at which the position vector sweeps out an angle, the direction perpendicular to the instantaneous plane of angular displacement, and the mass involved, as well as how this mass is distributed in space. By retaining this vector nature of angular momentum, the general nature of the equations is also retained, and can describe any sort of three-dimensional motion about the center of rotation -- circular, linear, or otherwise. In vector notation, the orbital angular momentum of a point particle in motion about the origin can be expressed as: $\mathbf{L} = I\boldsymbol{\omega},$ where - $I = r^2m$ is the moment of inertia for a point mass, - $\boldsymbol{\omega}=\frac{\mathbf{r}\times\mathbf{v}}{r^2}$ is the orbital angular velocity of the particle about the origin, - $\mathbf{r}$ is the position vector of the particle relative to the origin, and $r=\left\vert\mathbf{r}\right\vert$, - $\mathbf{v}$ is the linear velocity of the particle relative to the origin, and - $m$ is the mass of the particle. This can be expanded, reduced, and by the rules of vector algebra, rearranged: $\begin{align} \mathbf{L} &= \left(r^2m\right)\left(\frac{\mathbf{r}\times\mathbf{v}}{r^2}\right) \\ &= m\left(\mathbf{r}\times\mathbf{v}\right) \\ &= \mathbf{r}\times m\mathbf{v} \\ &= \mathbf{r}\times\mathbf{p}, \end{align}$ which is the cross product of the position vector $\mathbf{r}$ and the linear momentum $\mathbf{p} = m\mathbf{v}$ of the particle. By the definition of the cross product, the $\mathbf{L}$ vector is perpendicular to both $\mathbf{r}$ and $\mathbf{p}$. It is directed perpendicular to the plane of angular displacement, as indicated by the right-hand rule -- so that the angular velocity is seen as counter-clockwise from the head of the vector. Conversely, the $\mathbf{L}$ vector defines the plane in which $\mathbf{r}$ and $\mathbf{p}$ lie. By defining a unit vector $\mathbf{\hat{u}}$ perpendicular to the plane of angular displacement, a scalar angular speed $\omega$ results, where $\omega\mathbf{\hat{u}} = \boldsymbol{\omega},$ and $\omega = \frac{v_\perp}{r},$ where $v_\perp$ is the perpendicular component of the motion, as above. The two-dimensional scalar equations of the previous section can thus be given direction: $\begin{align} \mathbf{L} &= I\boldsymbol{\omega}\\ &= I\omega\mathbf{\hat{u}}\\ &= \left(r^2m\right)\omega\mathbf{\hat{u}}\\ &= rmv_\perp \mathbf{\hat{u}}\\ &= r_\perp mv\mathbf{\hat{u}}, \end{align}$ and $\mathbf{L} = rmv\mathbf{\hat{u}}$ for circular motion, where all of the motion is perpendicular to the radius $r$. In the spherical coordinate system the angular momentum vector expresses as : \\mathbf{L} = ` m \mathbf{r} \times \mathbf{v} = m r^2 \left(\dot\theta\,\hat{\boldsymbol\varphi} - \dot\varphi \sin\theta\,\mathbf{\hat{\boldsymbol\theta}}\right). ` ## Analogy to linear momentum {#analogy_to_linear_momentum} Angular momentum can be described as the rotational analog of linear momentum. Like linear momentum it involves elements of mass and displacement. Unlike linear momentum it also involves elements of position and shape. Many problems in physics involve matter in motion about some certain point in space, be it in actual rotation about it, or simply moving past it, where it is desired to know what effect the moving matter has on the point---can it exert energy upon it or perform work about it? Energy, the ability to do work, can be stored in matter by setting it in motion---a combination of its inertia and its displacement. Inertia is measured by its mass, and displacement by its velocity. Their product, $\begin{align} (\text{amount of inertia}) \times (\text{amount of displacement})&=\text{amount of (inertia⋅displacement)}\\ \text{mass} \times \text{velocity} &= \text{momentum}\\ m \times v &= p\\ \end{align}$ is the matter\'s momentum. Referring this momentum to a central point introduces a complication: the momentum is not applied to the point directly. For instance, a particle of matter at the outer edge of a wheel is, in effect, at the end of a lever of the same length as the wheel\'s radius, its momentum turning the lever about the center point. This imaginary lever is known as the moment arm. It has the effect of multiplying the momentum\'s effort in proportion to its length, an effect known as a moment. Hence, the particle\'s momentum referred to a particular point, $\begin{align} (\text{moment arm}) \times (\text{amount of inertia}) \times (\text{amount of displacement})&=\text{moment of (inertia⋅displacement)}\\ \text{length} \times \text{mass} \times \text{velocity} &= \text{moment of momentum}\\ r \times m \times v &= L\\ \end{align}$ is the angular momentum, sometimes called, as here, the moment of momentum of the particle versus that particular center point. The equation $L = rmv$ combines a moment (a mass $m$ turning moment arm $r$) with a linear (straight-line equivalent) speed $v$. Linear speed referred to the central point is simply the product of the distance $r$ and the angular speed $\omega$ versus the point: $v=r\omega,$ another moment. Hence, angular momentum contains a double moment: $L = rmr \omega.$ Simplifying slightly, $L = r^2 m\omega,$ the quantity $r^2m$ is the particle\'s moment of inertia, sometimes called the second moment of mass. It is a measure of rotational inertia. The above analogy of the translational momentum and rotational momentum can be expressed in vector form: - $\mathbf p = m\mathbf v$ for linear motion - $\mathbf L = I\boldsymbol\omega$ for rotation The direction of momentum is related to the direction of the velocity for linear movement. The direction of angular momentum is related to the angular velocity of the rotation. Because moment of inertia is a crucial part of the spin angular momentum, the latter necessarily includes all of the complications of the former, which is calculated by multiplying elementary bits of the mass by the squares of their distances from the center of rotation. Therefore, the total moment of inertia, and the angular momentum, is a complex function of the configuration of the matter about the center of rotation and the orientation of the rotation for the various bits. For a rigid body, for instance a wheel or an asteroid, the orientation of rotation is simply the position of the rotation axis versus the matter of the body. It may or may not pass through the center of mass, or it may lie completely outside of the body. For the same body, angular momentum may take a different value for every possible axis about which rotation may take place. It reaches a minimum when the axis passes through the center of mass. For a collection of objects revolving about a center, for instance all of the bodies of the Solar System, the orientations may be somewhat organized, as is the Solar System, with most of the bodies\' axes lying close to the system\'s axis. Their orientations may also be completely random. In brief, the more mass and the farther it is from the center of rotation (the longer the moment arm), the greater the moment of inertia, and therefore the greater the angular momentum for a given angular velocity. In many cases the moment of inertia, and hence the angular momentum, can be simplified by, $I=k^2m,$where $k$ is the radius of gyration, the distance from the axis at which the entire mass $m$ may be considered as concentrated. Similarly, for a point mass $m$ the moment of inertia is defined as, $I=r^2m$where $r$ is the radius of the point mass from the center of rotation, and for any collection of particles $m_i$ as the sum, $\sum_i I_i = \sum_i r_i^2m_i .$ Angular momentum\'s dependence on position and shape is reflected in its units versus linear momentum: kg⋅m^2^/s or N⋅m⋅s for angular momentum versus kg⋅m/s or N⋅s for linear momentum. When calculating angular momentum as the product of the moment of inertia times the angular velocity, the angular velocity must be expressed in radians per second, where the radian assumes the dimensionless value of unity. (When performing dimensional analysis, it may be productive to use orientational analysis which treats radians as a base unit, but this is not done in the International system of units). The units if angular momentum can be interpreted as torque⋅time. An object with angular momentum of `{{nowrap\|''L'' N⋅m⋅s}}`{=mediawiki} can be reduced to zero angular velocity by an angular impulse of `{{nowrap\|''L'' N⋅m⋅s}}`{=mediawiki}. The plane perpendicular to the axis of angular momentum and passing through the center of mass is sometimes called the invariable plane, because the direction of the axis remains fixed if only the interactions of the bodies within the system, free from outside influences, are considered. One such plane is the invariable plane of the Solar System. ### Angular momentum and torque {#angular_momentum_and_torque} Newton\'s second law of motion can be expressed mathematically, $\mathbf{F} = m\mathbf{a},$ or force = mass × acceleration. The rotational equivalent for point particles may be derived as follows: $\mathbf{L} = I\boldsymbol{\omega}$ which means that the torque (i.e. the time derivative of the angular momentum) is $\boldsymbol{\tau} = \frac{dI}{dt}\boldsymbol{\omega} + I\frac{d\boldsymbol{\omega}}{dt}.$ Because the moment of inertia is $mr^2$, it follows that $\frac{dI}{dt} = 2mr\frac{dr}{dt} = 2rp_{\|\|}$, and $\frac{d\mathbf{L}}{dt} = I\frac{d\boldsymbol{\omega}}{dt} + 2rp_{\|\|}\boldsymbol{\omega},$ which, reduces to $\boldsymbol{\tau} = I\boldsymbol{\alpha} + 2rp_{\|\|}\boldsymbol{\omega}.$ This is the rotational analog of Newton\'s second law. Note that the torque is not necessarily proportional or parallel to the angular acceleration (as one might expect). The reason for this is that the moment of inertia of a particle can change with time, something that cannot occur for ordinary mass. ## Conservation of angular momentum {#conservation_of_angular_momentum} ### General considerations {#general_considerations} A rotational analog of Newton\'s third law of motion might be written, \"In a closed system, no torque can be exerted on any matter without the exertion on some other matter of an equal and opposite torque about the same axis.\" Hence, angular momentum can be exchanged between objects in a closed system, but total angular momentum before and after an exchange remains constant (is conserved). Seen another way, a rotational analogue of Newton\'s first law of motion might be written, \"A rigid body continues in a state of uniform rotation unless acted upon by an external influence.\" Thus with no external influence to act upon it, the original angular momentum of the system remains constant. The conservation of angular momentum is used in analyzing central force motion. If the net force on some body is directed always toward some point, the center, then there is no torque on the body with respect to the center, as all of the force is directed along the radius vector, and none is perpendicular to the radius. Mathematically, torque $\boldsymbol{\tau} = \mathbf{r} \times \mathbf{F} = \mathbf{0},$ because in this case $\mathbf{r}$ and $\mathbf{F}$ are parallel vectors. Therefore, the angular momentum of the body about the center is constant. This is the case with gravitational attraction in the orbits of planets and satellites, where the gravitational force is always directed toward the primary body and orbiting bodies conserve angular momentum by exchanging distance and velocity as they move about the primary. Central force motion is also used in the analysis of the Bohr model of the atom. For a planet, angular momentum is distributed between the spin of the planet and its revolution in its orbit, and these are often exchanged by various mechanisms. The conservation of angular momentum in the Earth--Moon system results in the transfer of angular momentum from Earth to Moon, due to tidal torque the Moon exerts on the Earth. This in turn results in the slowing down of the rotation rate of Earth, at about 65.7 nanoseconds per day, and in gradual increase of the radius of Moon\'s orbit, at about 3.82 centimeters per year. The conservation of angular momentum explains the angular acceleration of an ice skater as they bring their arms and legs close to the vertical axis of rotation. By bringing part of the mass of their body closer to the axis, they decrease their body\'s moment of inertia. Because angular momentum is the product of moment of inertia and angular velocity, if the angular momentum remains constant (is conserved), then the angular velocity (rotational speed) of the skater must increase. The same phenomenon results in extremely fast spin of compact stars (like white dwarfs, neutron stars and black holes) when they are formed out of much larger and slower rotating stars. Conservation is not always a full explanation for the dynamics of a system but is a key constraint. For example, a spinning top is subject to gravitational torque making it lean over and change the angular momentum about the nutation axis, but neglecting friction at the point of spinning contact, it has a conserved angular momentum about its spinning axis, and another about its precession axis. Also, in any planetary system, the planets, star(s), comets, and asteroids can all move in numerous complicated ways, but only so that the angular momentum of the system is conserved. Noether\'s theorem states that every conservation law is associated with a symmetry (invariant) of the underlying physics. The symmetry associated with conservation of angular momentum is rotational invariance. The fact that the physics of a system is unchanged if it is rotated by any angle about an axis implies that angular momentum is conserved. ### Relation to Newton\'s second law of motion {#relation_to_newtons_second_law_of_motion} While angular momentum total conservation can be understood separately from Newton\'s laws of motion as stemming from Noether\'s theorem in systems symmetric under rotations, it can also be understood simply as an efficient method of calculation of results that can also be otherwise arrived at directly from Newton\'s second law, together with laws governing the forces of nature (such as Newton\'s third law, Maxwell\'s equations and Lorentz force). Indeed, given initial conditions of position and velocity for every point, and the forces at such a condition, one may use Newton\'s second law to calculate the second derivative of position, and solving for this gives full information on the development of the physical system with time. Note, however, that this is no longer true in quantum mechanics, due to the existence of particle spin, which is an angular momentum that cannot be described by the cumulative effect of point-like motions in space. As an example, consider decreasing of the moment of inertia, e.g. when a figure skater is pulling in their hands, speeding up the circular motion. In terms of angular momentum conservation, we have, for angular momentum L, moment of inertia I and angular velocity ω: $0 = dL = d (I\cdot \omega) = dI \cdot \omega + I \cdot d\omega$ Using this, we see that the change requires an energy of: $dE = d \left(\tfrac{1}{2} I\cdot \omega^2\right) = \tfrac{1}{2} dI \cdot \omega^2 + I \cdot \omega \cdot d\omega = -\tfrac{1}{2} dI \cdot \omega^2$ so that a decrease in the moment of inertia requires investing energy. This can be compared to the work done as calculated using Newton\'s laws. Each point in the rotating body is accelerating, at each point of time, with radial acceleration of: $-r\cdot \omega^2$ Let us observe a point of mass m, whose position vector relative to the center of motion is perpendicular to the z-axis at a given point of time, and is at a distance z. The centripetal force on this point, keeping the circular motion, is: $-m\cdot z\cdot \omega^2$ Thus the work required for moving this point to a distance dz farther from the center of motion is: $dW = -m\cdot z\cdot \omega^2\cdot dz = -m\cdot \omega^2\cdot d\left(\tfrac{1}{2} z^2\right)$ For a non-pointlike body one must integrate over this, with m replaced by the mass density per unit z. This gives: $dW = - \tfrac{1}{2}dI \cdot \omega^2$ which is exactly the energy required for keeping the angular momentum conserved. Note, that the above calculation can also be performed per mass, using kinematics only. Thus the phenomena of figure skater accelerating tangential velocity while pulling their hands in, can be understood as follows in layman\'s language: The skater\'s palms are not moving in a straight line, so they are constantly accelerating inwards, but do not gain additional speed because the accelerating is always done when their motion inwards is zero. However, this is different when pulling the palms closer to the body: The acceleration due to rotation now increases the speed; but because of the rotation, the increase in speed does not translate to a significant speed inwards, but to an increase of the rotation speed. ### Stationary-action principle {#stationary_action_principle} In classical mechanics it can be shown that the rotational invariance of action functionals implies conservation of angular momentum. The action is defined in classical physics as a functional of positions, $x_i (t)$ often represented by the use of square brackets, and the final and initial times. It assumes the following form in cartesian coordinates$$S\left([x_{i}];t_{1},t_{2}\right)\equiv\int_{t_{1}}^{t_{2}}d t\left(\frac{1}{2}m\frac{d x_{i}}{d t}\ \frac{d x_{i}}{d t}-V(x_{i})\right)$$where the repeated indices indicate summation over the index. If the action is invariant of an infinitesimal transformation, it can be mathematically stated as: $\delta S = S\left([x_{i}+\delta x_i];t_{1},t_{2}\right)-S\left([x_{i}];t_{1},t_{2}\right) =0$. Under the transformation, $x_i \rightarrow x_i + \delta x_i$, the action becomes: $S\left([x_{i}+\delta x_i];t_{1},t_{2}\right)=\!\int_{t_{1}}^{t_{2}}d t\left(\frac{1}{2}m\frac{d(x_{i}+\delta x_{i})}{d t}\frac{d(x_{i}+\delta x_{i})}{d t}-V(x_{i}+\delta x_{i})\right)$ where we can employ the expansion of the terms up-to first order in $\delta x_i$: $\begin{align} \frac{d(x_i+\delta x_i)}{d t} \frac{d( x_{i}+\delta x_{i})}{ d t } &\simeq\frac{d x_{i}}{d t} \frac{d x_{i}}{d t}-2\frac{d^{2}x_{i}}{d t^{2}}\delta x_{i}+2\frac{d}{d t}\left(\delta x_{i}\frac{d x_{i}}{d t}\right)\\ V(x_{i}+\delta x_{i}) & \simeq V(x_{i})+\delta x_{i}\frac{\partial V}{\partial x_i}\\ \end{align}$giving the following change in action: $S[x_{i}+\delta x_{i}]\simeq S[x_{i}]+\int_{t_{1}}^{t_{2}}d t\,\delta x_{i}\left(- \frac{\partial V}{\partial x_i}-m{\frac{d^{2}x_{i}}{d t^{2}}}\right)+m\int_{t_{1}}^{t_{2}}d t{\frac{d}{d t}}\left(\delta x_{i}{\frac{d x_{i}}{d t}}\right).$ Since all rotations can be expressed as matrix exponential of skew-symmetric matrices, i.e. as $R(\hat n,\theta) = e^{M \theta}$ where $M$ is a skew-symmetric matrix and $\theta$ is angle of rotation, we can express the change of coordinates due to the rotation $R(\hat n,\delta \theta )$, up-to first order of infinitesimal angle of rotation, $\delta \theta$ as: $\delta x_i = M_{ij} x_j \delta \theta .$ Combining the equation of motion and rotational invariance of action, we get from the above equations that$$0=\delta S=\int_{t_{1}}^{t_{2}}d t\frac{d}{d t}\left(m\frac{d x_{i}}{d t}\delta x_{i}\right)= M_{i j}\,\delta \theta \, m \,x_{j}\frac{d x_{i}}{d t}\Bigg\vert_{t_{1}}^{t_{2}}$$Since this is true for any matrix $M_{ij}$ that satisfies $M_{ij} = - M_{ji} ,$ it results in the conservation of the following quantity: $\ell_{ij}(t) := m\left(x_i \frac{dx_j}{dt}-x_j \frac{dx_i}{dt}\right),$ as $\ell_{ij}(t_1)=\ell_{ij}(t_2)$. This corresponds to the conservation of angular momentum throughout the motion. ### Lagrangian formalism {#lagrangian_formalism} In Lagrangian mechanics, angular momentum for rotation around a given axis, is the conjugate momentum of the generalized coordinate of the angle around the same axis. For example, $L_z$, the angular momentum around the z axis, is: $L_z = \frac{\partial \cal{L}}{\partial \dot\theta_z}$ where $\cal{L}$ is the Lagrangian and $\theta_z$ is the angle around the z axis. Note that $\dot\theta_z$, the time derivative of the angle, is the angular velocity $\omega_z$. Ordinarily, the Lagrangian depends on the angular velocity through the kinetic energy: The latter can be written by separating the velocity to its radial and tangential part, with the tangential part at the x-y plane, around the z-axis, being equal to: $\sum_i \tfrac{1}{2}m_i {v_T}_i^2 = \sum_i \tfrac{1}{2} m_i \left(x_i^2 + y_i^2\right) { {\omega_z}_i}^2$ where the subscript i stands for the i-th body, and m, v~T~ and ω~z~ stand for mass, tangential velocity around the z-axis and angular velocity around that axis, respectively. For a body that is not point-like, with density ρ, we have instead: $\frac{1}{2}\int \rho(x,y,z) \left(x_i^2 + y_i^2\right) { {\omega_z}_i}^2\,dx\,dy = \frac{1}{2} {I_z}_i { {\omega_z}_i}^2$ where integration runs over the area of the body, and I~z~ is the moment of inertia around the z-axis. Thus, assuming the potential energy does not depend on ω~z~ (this assumption may fail for electromagnetic systems), we have the angular momentum of the ith object: $\begin{align} {L_z}_i &= \frac{\partial \cal{L} }{\partial { {\omega_z}_i} } = \frac{\partial E_k}{\partial { {\omega_z}_i} } \\ &= {I_z}_i \cdot {\omega_z}_i \end{align}$ We have thus far rotated each object by a separate angle; we may also define an overall angle θ~z~ by which we rotate the whole system, thus rotating also each object around the z-axis, and have the overall angular momentum: $L_z = \sum_i {I_z}_i \cdot {\omega_z}_i$ From Euler--Lagrange equations it then follows that: $0 = \frac{\partial \cal{L} }{\partial { {\theta_z}_i} } - \frac{d}{dt}\left(\frac{\partial \cal{L} }{\partial { {\dot\theta_z}_i}}\right) = \frac{\partial \cal{L} }{\partial { {\theta_z}_i} } - \frac{d{L_z}_i}{dt}$ Since the lagrangian is dependent upon the angles of the object only through the potential, we have: $\frac{d{L_z}_i}{dt} = \frac{\partial \cal{L}}{\partial { {\theta_z}_i} } = -\frac{\partial V}{\partial { {\theta_z}_i} }$ which is the torque on the ith object. Suppose the system is invariant to rotations, so that the potential is independent of an overall rotation by the angle θ~z~ (thus it may depend on the angles of objects only through their differences, in the form $V({\theta_z}_i, {\theta_z}_j) = V({\theta_z}_i - {\theta_z}_j)$). We therefore get for the total angular momentum: $\frac{d L_z}{dt} = -\frac{\partial V}{\partial {\theta_z} } = 0$ And thus the angular momentum around the z-axis is conserved. This analysis can be repeated separately for each axis, giving conversation of the angular momentum vector. However, the angles around the three axes cannot be treated simultaneously as generalized coordinates, since they are not independent; in particular, two angles per point suffice to determine its position. While it is true that in the case of a rigid body, fully describing it requires, in addition to three translational degrees of freedom, also specification of three rotational degrees of freedom; however these cannot be defined as rotations around the Cartesian axes (see Euler angles). This caveat is reflected in quantum mechanics in the non-trivial commutation relations of the different components of the angular momentum operator. ### Hamiltonian formalism {#hamiltonian_formalism} Equivalently, in Hamiltonian mechanics the Hamiltonian can be described as a function of the angular momentum. As before, the part of the kinetic energy related to rotation around the z-axis for the ith object is: $\frac{1}{2} {I_z}_i { {\omega_z}_i}^2 = \frac{ { {L_z}_i}^2}{2 {I_z}_i}$ which is analogous to the energy dependence upon momentum along the z-axis, $\frac{ { {p_z}_i}^2}{ {2m}_i}$. Hamilton\'s equations relate the angle around the z-axis to its conjugate momentum, the angular momentum around the same axis: $\begin{align} \frac{d{\theta_z}_i}{dt} &= \frac{\partial \mathcal{H} }{\partial {L_z}_i} = \frac{ {L_z}_i}{ {I_z}_i} \\ \frac{d{L_z}_i}{dt} &= -\frac{\partial \mathcal{H} }{\partial {\theta_z}_i} = -\frac{\partial V}{\partial {\theta_z}_i} \end{align}$ The first equation gives ${L_z}_i = {I_z}_i \cdot { {\dot{\theta}_z}_i} = {I_z}_i \cdot {\omega_z}_i$ And so we get the same results as in the Lagrangian formalism. Note, that for combining all axes together, we write the kinetic energy as: $E_k = \frac{1}{2}\sum_i \frac{\|\mathbf{p}_i\|^2}{2m_i} = \sum_i \left(\frac{ {p_r}_i^2}{2m_i} + \frac{1}{2} {\mathbf{L}_i}^\textsf{T}{I_i}^{-1} \mathbf{L}_i\right)$ where p~r~ is the momentum in the radial direction, and the moment of inertia is a 3-dimensional matrix; bold letters stand for 3-dimensional vectors. For point-like bodies we have: $E_k = \sum_i \left(\frac{ {p_r}_i^2}{2m_i} + \frac{\|{\mathbf{L}_i}\|^2}{2m_i {r_i}^2}\right)$ This form of the kinetic energy part of the Hamiltonian is useful in analyzing central potential problems, and is easily transformed to a quantum mechanical work frame (e.g. in the hydrogen atom problem). ## Angular momentum in orbital mechanics {#angular_momentum_in_orbital_mechanics} While in classical mechanics the language of angular momentum can be replaced by Newton\'s laws of motion, it is particularly useful for motion in central potential such as planetary motion in the solar system. Thus, the orbit of a planet in the solar system is defined by its energy, angular momentum and angles of the orbit major axis relative to a coordinate frame. In astrodynamics and celestial mechanics, a quantity closely related to angular momentum is defined as $\mathbf{h} = \mathbf{r} \times \mathbf{v},$ called specific angular momentum. Note that $\mathbf{L} = m\mathbf{h}.$ Mass is often unimportant in orbital mechanics calculations, because motion of a body is determined by gravity. The primary body of the system is often so much larger than any bodies in motion about it that the gravitational effect of the smaller bodies on it can be neglected; it maintains, in effect, constant velocity. The motion of all bodies is affected by its gravity in the same way, regardless of mass, and therefore all move approximately the same way under the same conditions. ## Solid bodies {#solid_bodies} Angular momentum is also an extremely useful concept for describing rotating rigid bodies such as a gyroscope or a rocky planet. For a continuous mass distribution with density function ρ(r), a differential volume element dV with position vector r within the mass has a mass element dm = ρ(r)dV. Therefore, the infinitesimal angular momentum of this element is: $d\mathbf{L} = \mathbf{r}\times dm \mathbf{v} = \mathbf{r}\times \rho(\mathbf{r}) dV \mathbf{v} = dV \mathbf{r}\times \rho(\mathbf{r}) \mathbf{v}$ and integrating this differential over the volume of the entire mass gives its total angular momentum: $\mathbf{L}=\int_V dV \mathbf{r}\times \rho(\mathbf{r}) \mathbf{v}$ In the derivation which follows, integrals similar to this can replace the sums for the case of continuous mass. ### Collection of particles {#collection_of_particles} For a collection of particles in motion about an arbitrary origin, it is informative to develop the equation of angular momentum by resolving their motion into components about their own center of mass and about the origin. Given, - $m_i$ is the mass of particle $i$, - $\mathbf{R}_i$ is the position vector of particle $i$ w.r.t. the origin, - $\mathbf{V}_i$ is the velocity of particle $i$ w.r.t. the origin, - $\mathbf{R}$ is the position vector of the center of mass w.r.t. the origin, - $\mathbf{V}$ is the velocity of the center of mass w.r.t. the origin, - $\mathbf{r}_i$ is the position vector of particle $i$ w.r.t. the center of mass, - $\mathbf{v}_i$ is the velocity of particle $i$ w.r.t. the center of mass, The total mass of the particles is simply their sum, $M=\sum_i m_i.$ The position vector of the center of mass is defined by, $M\mathbf{R}=\sum_i m_i \mathbf{R}_i.$ By inspection, : $\mathbf{R}_i = \mathbf{R} + \mathbf{r}_i$ and $\mathbf{V}_i = \mathbf{V} + \mathbf{v}_i.$ The total angular momentum of the collection of particles is the sum of the angular momentum of each particle, `{{Equation box 1 \|indent=: \|equation =<math>\mathbf{L} = \sum_i \left( \mathbf{R}_i \times m_i \mathbf{V}_i \right)</math>     ({{EquationRef\|1}}) }}`{=mediawiki} Expanding $\mathbf{R}_i$, : \\begin{align} ` \mathbf{L} &= \sum_i \left[\left(\mathbf{R} + \mathbf{r}_i\right) \times m_i\mathbf{V}_i \right] \\`\ ` &= \sum_i \left[ \mathbf{R} \times m_i\mathbf{V}_i + \mathbf{r}_i \times m_i\mathbf{V}_i \right]` \\end{align} Expanding $\mathbf{V}_i$, : \\begin{align} ` \mathbf{L} &= \sum_i \left[ \mathbf{R} \times m_i\left(\mathbf{V} + \mathbf{v}_i\right) + \mathbf{r}_i \times m_i(\mathbf{V} + \mathbf{v}_i) \right ]\\`\ ` &= \sum_i \left[ \mathbf{R} \times m_i\mathbf{V} + \mathbf{R} \times m_i\mathbf{v}_i + \mathbf{r}_i \times m_i\mathbf{V} + \mathbf{r}_i \times m_i\mathbf{v}_i \right]\\`\ ` &= \sum_i \mathbf{R} \times m_i\mathbf{V} + \sum_i \mathbf{R} \times m_i\mathbf{v}_i + \sum_i \mathbf{r}_i \times m_i\mathbf{V} + \sum_i \mathbf{r}_i \times m_i\mathbf{v}_i` \\end{align} It can be shown that (see sidebar), ---------------------------------------------------------------------------------------------------------------------------- Prove that $\sum_i m_i\mathbf{r}_i = \mathbf{0}$ $\begin{align} \mathbf{r}_i &= \mathbf{R}_i - \mathbf{R} \\ m_i\mathbf{r}_i &= m_i\left(\mathbf{R}_i - \mathbf{R}\right) \\ \sum_i m_i\mathbf{r}_i &= \sum_i m_i\left(\mathbf{R}_i - \mathbf{R}\right)\\ &= \sum_i (m_i\mathbf{R}_i - m_i\mathbf{R})\\ &= \sum_i m_i\mathbf{R}_i - \sum_i m_i\mathbf{R}\\ &= \sum_i m_i\mathbf{R}_i - \left( \sum_i m_i \right) \mathbf{R}\\ &= \sum_i m_i\mathbf{R}_i - M\mathbf{R} \end{align}$ which, by the definition of the center of mass, is $\mathbf{0},$ and similarly for $\sum_i m_i \mathbf{v}_i.$ ---------------------------------------------------------------------------------------------------------------------------- : $\sum_i m_i\mathbf{r}_i = \mathbf{0}$ and $\sum_i m_i\mathbf{v}_i = \mathbf{0},$ therefore the second and third terms vanish, : $\mathbf{L} = \sum_i \mathbf{R} \times m_i\mathbf{V} + \sum_i \mathbf{r}_i \times m_i\mathbf{v}_i .$ The first term can be rearranged, : $\sum_i \mathbf{R} \times m_i\mathbf{V} = \mathbf{R} \times \sum_i m_i\mathbf{V} = \mathbf{R} \times M\mathbf{V},$ and total angular momentum for the collection of particles is finally, `{{Equation box 1 \|indent=: \|equation =<math>\mathbf{L} = \mathbf{R} \times M\mathbf{V} + \sum_i \mathbf{r}_i \times m_i\mathbf{v}_i </math>     ({{EquationRef\|2}}) }}`{=mediawiki} The first term is the angular momentum of the center of mass relative to the origin. Similar to `{{section link\|#Single particle}}`{=mediawiki}, below, it is the angular momentum of one particle of mass M at the center of mass moving with velocity V. The second term is the angular momentum of the particles moving relative to the center of mass, similar to `{{section link\|#Fixed center of mass}}`{=mediawiki}, below. The result is general---the motion of the particles is not restricted to rotation or revolution about the origin or center of mass. The particles need not be individual masses, but can be elements of a continuous distribution, such as a solid body. Rearranging equation (`{{EquationNote\|2}}`{=mediawiki}) by vector identities, multiplying both terms by \"one\", and grouping appropriately, $\begin{align} \mathbf{L} &= M(\mathbf{R} \times \mathbf{V}) + \sum_i \left[m_i\left(\mathbf{r}_i \times \mathbf{v}_i\right)\right], \\ &= \frac{R^2}{R^2}M\left(\mathbf{R} \times \mathbf{V}\right) + \sum_i \left[ \frac{r_i^2}{r_i^2}m_i\left(\mathbf{r}_i \times \mathbf{v}_i\right)\right] , \\ &= R^2M \left( \frac{\mathbf{R} \times \mathbf{V} }{R^2} \right) + \sum_i \left[ r_i^2 m_i \left( \frac{\mathbf{r}_i \times \mathbf{v}_i}{r_i^2} \right) \right] , \\ \end{align}$ gives the total angular momentum of the system of particles in terms of moment of inertia $I$ and angular velocity $\boldsymbol{\omega}$, #### Single particle case {#single_particle_case} In the case of a single particle moving about the arbitrary origin, $\begin{align} \mathbf{r}_i &= \mathbf{v}_i = \mathbf{0}, \\ \mathbf{r} &= \mathbf{R}, \\ \mathbf{v} &= \mathbf{V}, \\ m &= M, \end{align}$ $\sum_i \mathbf{r}_i \times m_i\mathbf{v}_i = \mathbf{0},$ $\sum_i I_i\boldsymbol{\omega}_i = \mathbf{0},$ and equations (`{{EquationNote\|2}}`{=mediawiki}) and (`{{EquationNote\|3}}`{=mediawiki}) for total angular momentum reduce to, $\mathbf{L} = \mathbf{R} \times m\mathbf{V} = I_R\boldsymbol{\omega}_R.$ #### Case of a fixed center of mass {#case_of_a_fixed_center_of_mass} For the case of the center of mass fixed in space with respect to the origin, $\mathbf{V} = \mathbf{0},$ $\mathbf{R} \times M\mathbf{V} = \mathbf{0},$ $I_R\boldsymbol{\omega}_R = \mathbf{0},$ and equations (`{{EquationNote\|2}}`{=mediawiki}) and (`{{EquationNote\|3}}`{=mediawiki}) for total angular momentum reduce to, $\mathbf{L} = \sum_i \mathbf{r}_i \times m_i\mathbf{v}_i = \sum_i I_i\boldsymbol{\omega}_i.$ ## Angular momentum in general relativity {#angular_momentum_in_general_relativity} Main article: Relativistic angular momentum In modern (20th century) theoretical physics, angular momentum (not including any intrinsic angular momentum -- see below) is described using a different formalism, instead of a classical pseudovector. In this formalism, angular momentum is the 2-form Noether charge associated with rotational invariance. As a result, angular momentum is generally not conserved locally for general curved spacetimes, unless they have rotational symmetry; whereas globally the notion of angular momentum itself only makes sense if the spacetime is asymptotically flat. If the spacetime is only axially symmetric like for the Kerr metric, the total angular momentum is not conserved but $p_{\phi}$ is conserved which is related to the invariance of rotating around the symmetry-axis, where note that $p_{\phi}=g_{\phi \mu}p^{\mu}=mg_{\mu \phi} dX^{\mu}/d\tau$ where $g_{\mu\nu}$ is the metric, $m=\sqrt{\|p_\mu p^{\mu}\|}$ is the rest mass, $dX^{\mu}/d\tau$ is the four-velocity, and $X^{\mu}=(t,r,\theta,\phi)$ is the four-position in spherical coordinates. In classical mechanics, the angular momentum of a particle can be reinterpreted as a plane element: $\mathbf{L} = \mathbf{r} \wedge \mathbf{p} \,,$ in which the exterior product (∧) replaces the cross product (×) (these products have similar characteristics but are nonequivalent). This has the advantage of a clearer geometric interpretation as a plane element, defined using the vectors x and p, and the expression is true in any number of dimensions. In Cartesian coordinates: $\begin{align} \mathbf{L} &= \left(xp_y - yp_x\right)\mathbf{e}_x \wedge \mathbf{e}_y + \left(yp_z - zp_y\right)\mathbf{e}_y \wedge \mathbf{e}_z + \left(zp_x - xp_z\right)\mathbf{e}_z \wedge \mathbf{e}_x\\ &= L_{xy}\mathbf{e}_x \wedge \mathbf{e}_y + L_{yz}\mathbf{e}_y \wedge \mathbf{e}_z + L_{zx}\mathbf{e}_z \wedge \mathbf{e}_x \,, \end{align}$ or more compactly in index notation: $L_{ij} = x_i p_j - x_j p_i\,.$ The angular velocity can also be defined as an anti-symmetric second order tensor, with components ω~ij~. The relation between the two anti-symmetric tensors is given by the moment of inertia which must now be a fourth order tensor: $L_{ij} = I_{ijk\ell} \omega_{k\ell} \,.$ Again, this equation in L and *ω\'\' as tensors is true in any number of dimensions. This equation also appears in the geometric algebra formalism, in whichLand*ω\'\' are bivectors, and the moment of inertia is a mapping between them. In relativistic mechanics, the relativistic angular momentum of a particle is expressed as an anti-symmetric tensor of second order: $M_{\alpha\beta} = X_\alpha P_\beta - X_\beta P_\alpha$ in terms of four-vectors, namely the four-position X and the four-momentum P, and absorbs the above L together with the moment of mass, i.e., the product of the relativistic mass of the particle and its center of mass, which can be thought of as describing the motion of its center of mass, since mass--energy is conserved. In each of the above cases, for a system of particles the total angular momentum is just the sum of the individual particle angular momenta, and the center of mass is for the system. ## Angular momentum in quantum mechanics {#angular_momentum_in_quantum_mechanics} In quantum mechanics, angular momentum (like other quantities) is expressed as an operator , and its one-dimensional projections have quantized eigenvalues. Angular momentum is subject to the Heisenberg uncertainty principle, implying that at any time, only one projection (also called \"component\") can be measured with definite precision; the other two then remain uncertain. Because of this, the axis of rotation of a quantum particle is undefined. Quantum particles do possess a type of non-orbital angular momentum called \"spin\", but this angular momentum does not correspond to a spinning motion. In relativistic quantum mechanics the above relativistic definition becomes a tensorial operator. ### Spin, orbital, and total angular momentum {#spin_orbital_and_total_angular_momentum} upright=1.25\\|thumb\\|Angular momenta of a classical object.`{{ubl \| '''Left:''' "spin" angular momentum '''S''' is really orbital angular momentum of the object at every point. \| '''Right:''' extrinsic orbital angular momentum '''L''' about an axis. \| '''Top:''' the [[moment of inertia tensor]] '''I''' and [[angular velocity]] '''ω''' ('''L''' is not always parallel to '''ω''').<ref>{{cite book\|title=Feynman's Lectures on Physics (volume 2)\|author1=R.P. Feynman \|author2=R.B. Leighton \|author3=M. Sands \|publisher=Addison–Wesley\|year=1964\|pages=31–7\|isbn=978-0-201-02117-2}}</ref> \| '''Bottom:''' momentum '''p''' and its radial position '''r''' from the axis. The total angular momentum (spin plus orbital) is '''J'''. For a ''quantum'' particle the interpretations are different; [[Spin (physics)\|particle spin]] does ''not'' have the above interpretation.}}`{=mediawiki} The classical definition of angular momentum as $\mathbf{L} = \mathbf{r}\times\mathbf{p}$ can be carried over to quantum mechanics, by reinterpreting r as the quantum position operator and p as the quantum momentum operator. L is then an operator, specifically called the orbital angular momentum operator. The components of the angular momentum operator satisfy the commutation relations of the Lie algebra so(3). Indeed, these operators are precisely the infinitesimal action of the rotation group on the quantum Hilbert space. (See also the discussion below of the angular momentum operators as the generators of rotations.) However, in quantum physics, there is another type of angular momentum, called spin angular momentum, represented by the spin operator S. Spin is often depicted as a particle literally spinning around an axis, but this is a misleading and inaccurate picture: spin is an intrinsic property of a particle, unrelated to any sort of motion in space and fundamentally different from orbital angular momentum. All elementary particles have a characteristic spin (possibly zero), and almost all elementary particles have nonzero spin. For example electrons have \"spin 1/2\" (this actually means \"spin ħ/2\"), photons have \"spin 1\" (this actually means \"spin ħ\"), and pi-mesons have spin 0. Finally, there is total angular momentum J, which combines both the spin and orbital angular momentum of all particles and fields. (For one particle, `{{nowrap\|'''J''' {{=}}`{=mediawiki} L + S}}.) Conservation of angular momentum applies to J, but not to L or S; for example, the spin--orbit interaction allows angular momentum to transfer back and forth between L and S, with the total remaining constant. Electrons and photons need not have integer-based values for total angular momentum, but can also have half-integer values. In molecules the total angular momentum F is the sum of the rovibronic (orbital) angular momentum N, the electron spin angular momentum S, and the nuclear spin angular momentum I. For electronic singlet states the rovibronic angular momentum is denoted J rather than N. As explained by Van Vleck, the components of the molecular rovibronic angular momentum referred to molecule-fixed axes have different commutation relations from those for the components about space-fixed axes. ### Quantization In quantum mechanics, angular momentum is quantized -- that is, it cannot vary continuously, but only in \"quantum leaps\" between certain allowed values. For any system, the following restrictions on measurement results apply, where $\hbar$ is the reduced Planck constant and $\hat n$ is any Euclidean vector such as x, y, or z: ------------------------------ -------------------------------------------------------------------------------------------------------------- If you measure\... The result can be\... $L_\hat{n}$ $\ldots, -2\hbar, -\hbar, 0, \hbar, 2\hbar, \ldots$ $S_\hat{n}$ or $J_\hat{n}$ $\ldots, -\frac{3}{2}\hbar, -\hbar, -\frac{1}{2}\hbar, 0, \frac{1}{2}\hbar, \hbar, \frac{3}{2}\hbar, \ldots$ $\begin{align} $\left[\hbar^2 n(n + 1)\right]$, where $n = 0, 1, 2, \ldots$ &L^2 \\ ={} &L_x^2 + L_y^2 + L_z^2 \end{align}$ $S^2$ or $J^2$ $\left[\hbar^2 n(n + 1)\right]$, where $n = 0, \tfrac{1}{2}, 1, \tfrac{3}{2}, \ldots$ ------------------------------ -------------------------------------------------------------------------------------------------------------- The reduced Planck constant $\hbar$ is tiny by everyday standards, about 10^−34^ J s, and therefore this quantization does not noticeably affect the angular momentum of macroscopic objects. However, it is very important in the microscopic world. For example, the structure of electron shells and subshells in chemistry is significantly affected by the quantization of angular momentum. Quantization of angular momentum was first postulated by Niels Bohr in his model of the atom and was later predicted by Erwin Schrödinger in his Schrödinger equation. ### Uncertainty In the definition $\mathbf{L}=\mathbf{r}\times\mathbf{p}$, six operators are involved: The position operators $r_x$, $r_y$, $r_z$, and the momentum operators $p_x$, $p_y$, $p_z$. However, the Heisenberg uncertainty principle tells us that it is not possible for all six of these quantities to be known simultaneously with arbitrary precision. Therefore, there are limits to what can be known or measured about a particle\'s angular momentum. It turns out that the best that one can do is to simultaneously measure both the angular momentum vector\'s magnitude and its component along one axis. The uncertainty is closely related to the fact that different components of an angular momentum operator do not commute, for example $L_xL_y \neq L_yL_x$. (For the precise commutation relations, see angular momentum operator.) ### Total angular momentum as generator of rotations {#total_angular_momentum_as_generator_of_rotations} As mentioned above, orbital angular momentum L is defined as in classical mechanics: $\mathbf{L}=\mathbf{r}\times\mathbf{p}$, but total angular momentum J is defined in a different, more basic way: J is defined as the \"generator of rotations\". More specifically, J is defined so that the operator $R(\hat{n},\phi) \equiv \exp\left(-\frac{i}{\hbar}\phi\, \mathbf{J}\cdot \hat{\mathbf{n} }\right)$ is the rotation operator that takes any system and rotates it by angle $\phi$ about the axis $\hat{\mathbf{n}}$. (The \"exp\" in the formula refers to operator exponential.) To put this the other way around, whatever our quantum Hilbert space is, we expect that the rotation group SO(3) will act on it. There is then an associated action of the Lie algebra so(3) of SO(3); the operators describing the action of so(3) on our Hilbert space are the (total) angular momentum operators. The relationship between the angular momentum operator and the rotation operators is the same as the relationship between Lie algebras and Lie groups in mathematics. The close relationship between angular momentum and rotations is reflected in Noether\'s theorem that proves that angular momentum is conserved whenever the laws of physics are rotationally invariant. ## Angular momentum in electrodynamics {#angular_momentum_in_electrodynamics} When describing the motion of a charged particle in an electromagnetic field, the canonical momentum P (derived from the Lagrangian for this system) is not gauge invariant. As a consequence, the canonical angular momentum L = r × P is not gauge invariant either. Instead, the momentum that is physical, the so-called kinetic momentum (used throughout this article), is (in SI units) $\mathbf{p} = m\mathbf{v} = \mathbf{P} - e \mathbf{A}$ where e is the electric charge of the particle and A the magnetic vector potential of the electromagnetic field. The gauge-invariant angular momentum, that is kinetic angular momentum, is given by $\mathbf{K}= \mathbf{r} \times ( \mathbf{P} - e\mathbf{A} )$ The interplay with quantum mechanics is discussed further in the article on canonical commutation relations. ## Angular momentum in optics {#angular_momentum_in_optics} In classical Maxwell electrodynamics the Poynting vector is a linear momentum density of electromagnetic field. $\mathbf{S}(\mathbf{r}, t) = \epsilon_0 c^2 \mathbf{E}(\mathbf{r}, t) \times \mathbf{B}(\mathbf{r}, t).$ The angular momentum density vector $\mathbf{L}(\mathbf{r}, t)$ is given by a vector product as in classical mechanics: $\mathbf{L}(\mathbf{r}, t) = \epsilon_0 \mu_0 \mathbf{r} \times \mathbf{S}(\mathbf{r}, t).$ The above identities are valid locally, i.e. in each space point $\mathbf{r}$ in a given moment $t$. ## Angular momentum in nature and the cosmos {#angular_momentum_in_nature_and_the_cosmos} Tropical cyclones and other related weather phenomena involve conservation of angular momentum in order to explain the dynamics. Winds revolve slowly around low pressure systems, mainly due to the coriolis effect. If the low pressure intensifies and the slowly circulating air is drawn toward the center, the molecules must speed up in order to conserve angular momentum. By the time they reach the center, the speeds become destructive. Johannes Kepler determined the laws of planetary motion without knowledge of conservation of momentum. However, not long after his discovery their derivation was determined from conservation of angular momentum. Planets move more slowly the further they are out in their elliptical orbits, which is explained intuitively by the fact that orbital angular momentum is proportional to the radius of the orbit. Since the mass does not change and the angular momentum is conserved, the velocity drops. Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon) and the primary planet that it orbits (e.g. Earth). The gravitational torque between the Moon and the tidal bulge of Earth causes the Moon to be constantly promoted to a slightly higher orbit (\~3.8 cm per year) and Earth to be decelerated (by −25.858 ± 0.003″/cy²) in its rotation (the length of the day increases by \~1.7 ms per century, +2.3 ms from tidal effect and −0.6 ms from post-glacial rebound). The Earth loses angular momentum which is transferred to the Moon such that the overall angular momentum is conserved. ## Angular momentum in engineering and technology {#angular_momentum_in_engineering_and_technology} Examples of using conservation of angular momentum for practical advantage are abundant. In engines such as steam engines or internal combustion engines, a flywheel is needed to efficiently convert the lateral motion of the pistons to rotational motion. Inertial navigation systems explicitly use the fact that angular momentum is conserved with respect to the inertial frame of space. Inertial navigation is what enables submarine trips under the polar ice cap, but are also crucial to all forms of modern navigation. Rifled bullets use the stability provided by conservation of angular momentum to be more true in their trajectory. The invention of rifled firearms and cannons gave their users significant strategic advantage in battle, and thus were a technological turning point in history. ## History Isaac Newton, in the Principia, hinted at angular momentum in his examples of the first law of motion, > A top, whose parts by their cohesion are perpetually drawn aside from rectilinear motions, does not cease its rotation, otherwise than as it is retarded by the air. The greater bodies of the planets and comets, meeting with less resistance in more free spaces, preserve their motions both progressive and circular for a much longer time. He did not further investigate angular momentum directly in the Principia, saying: > From such kind of reflexions also sometimes arise the circular motions of bodies about their own centers. But these are cases which I do not consider in what follows; and it would be too tedious to demonstrate every particular that relates to this subject. However, his geometric proof of the law of areas is an outstanding example of Newton\'s genius, and indirectly proves angular momentum conservation in the case of a central force. ### Law of Areas {#law_of_areas} #### Newton\'s derivation {#newtons_derivation} thumb\\|upright=1.25\\|Newton\'s derivation of the area law using geometric means As a planet orbits the Sun, the line between the Sun and the planet sweeps out equal areas in equal intervals of time. This had been known since Kepler expounded his second law of planetary motion. Newton derived a unique geometric proof, and went on to show that the attractive force of the Sun\'s gravity was the cause of all of Kepler\'s laws. During the first interval of time, an object is in motion from point A to point B. Undisturbed, it would continue to point c during the second interval. When the object arrives at B, it receives an impulse directed toward point S. The impulse gives it a small added velocity toward S, such that if this were its only velocity, it would move from B to V during the second interval. By the rules of velocity composition, these two velocities add, and point C is found by construction of parallelogram BcCV. Thus the object\'s path is deflected by the impulse so that it arrives at point C at the end of the second interval. Because the triangles SBc and SBC have the same base SB and the same height Bc or VC, they have the same area. By symmetry, triangle SBc also has the same area as triangle SAB, therefore the object has swept out equal areas SAB and SBC in equal times. At point C, the object receives another impulse toward S, again deflecting its path during the third interval from d to D. Thus it continues to E and beyond, the triangles SAB, SBc, SBC, SCd, SCD, SDe, SDE all having the same area. Allowing the time intervals to become ever smaller, the path ABCDE approaches indefinitely close to a continuous curve. Note that because this derivation is geometric, and no specific force is applied, it proves a more general law than Kepler\'s second law of planetary motion. It shows that the Law of Areas applies to any central force, attractive or repulsive, continuous or non-continuous, or zero. #### Conservation of angular momentum in the law of areas {#conservation_of_angular_momentum_in_the_law_of_areas} The proportionality of angular momentum to the area swept out by a moving object can be understood by realizing that the bases of the triangles, that is, the lines from S to the object, are equivalent to the radius `{{math\|<var>r</var>}}`{=mediawiki}, and that the heights of the triangles are proportional to the perpendicular component of velocity `{{math\|<var>v</var><sub>⊥</sub>}}`{=mediawiki}. Hence, if the area swept per unit time is constant, then by the triangular area formula `{{math\|{{sfrac\|1\|2}}(base)(height)}}`{=mediawiki}, the product `{{math\|(base)(height)}}`{=mediawiki} and therefore the product `{{math\|<var>rv</var><sub>⊥</sub>}}`{=mediawiki} are constant: if `{{math\|<var>r</var>}}`{=mediawiki} and the base length are decreased, `{{math\|<var>v</var><sub>⊥</sub>}}`{=mediawiki} and height must increase proportionally. Mass is constant, therefore angular momentum `{{math\|<var>rmv</var><sub>⊥</sub>}}`{=mediawiki} is conserved by this exchange of distance and velocity. In the case of triangle SBC, area is equal to `{{sfrac\|1\|2}}`{=mediawiki}(SB)(VC). Wherever C is eventually located due to the impulse applied at B, the product (SB)(VC), and therefore `{{math\|<var>rmv</var><sub>⊥</sub>}}`{=mediawiki} remain constant. Similarly so for each of the triangles. Another areal proof of conservation of angular momentum for any central force uses Mamikon\'s sweeping tangents theorem. ### After Newton {#after_newton} Leonhard Euler, Daniel Bernoulli, and Patrick d\'Arcy all understood angular momentum in terms of conservation of areal velocity, a result of their analysis of Kepler\'s second law of planetary motion. It is unlikely that they realized the implications for ordinary rotating matter. In 1736 Euler, like Newton, touched on some of the equations of angular momentum in his Mechanica without further developing them. Bernoulli wrote in a 1744 letter of a \"moment of rotational motion\", possibly the first conception of angular momentum as we now understand it. In 1799, Pierre-Simon Laplace first realized that a fixed plane was associated with rotation---his invariable plane. Louis Poinsot in 1803 began representing rotations as a line segment perpendicular to the rotation, and elaborated on the \"conservation of moments\". In 1852 Léon Foucault used a gyroscope in an experiment to display the Earth\'s rotation. William J. M. Rankine\'s 1858 Manual of Applied Mechanics defined angular momentum in the modern sense for the first time: > \... a line whose length is proportional to the magnitude of the angular momentum, and whose direction is perpendicular to the plane of motion of the body and of the fixed point, and such, that when the motion of the body is viewed from the extremity of the line, the radius-vector of the body seems to have right-handed rotation. In an 1872 edition of the same book, Rankine stated that \"The term angular momentum was introduced by Mr. Hayward,\" probably referring to R.B. Hayward\'s article On a Direct Method of estimating Velocities, Accelerations, and all similar Quantities with respect to Axes moveable in any manner in Space with Applications, which was introduced in 1856, and published in 1864. Rankine was mistaken, as numerous publications feature the term starting in the late 18th to early 19th centuries. However, Hayward\'s article apparently was the first use of the term and the concept seen by much of the English-speaking world. Before this, angular momentum was typically referred to as \"momentum of rotation\" in English.	2025-06-20T00:00:00
2,840	Plum pudding model	The plum pudding model is an obsolete scientific model of the atom. It was first proposed by J. J. Thomson in 1904 following his discovery of the electron in 1897, and was rendered obsolete by Ernest Rutherford\'s discovery of the atomic nucleus in 1911. The model tried to account for two properties of atoms then known: that there are electrons, and that atoms have no net electric charge. Logically there had to be an equal amount of positive charge to balance out the negative charge of the electrons. As Thomson had no idea as to the source of this positive charge, he tentatively proposed that it was everywhere in the atom, and that the atom was spherical. This was the mathematically simplest hypothesis to fit the available evidence, or lack thereof. In such a sphere, the negatively charged electrons would distribute themselves in a more or less even manner throughout the volume, simultaneously repelling each other while being attracted to the positive sphere\'s center. Despite Thomson\'s efforts, his model couldn\'t account for emission spectra and valencies. Based on experimental studies of alpha particle scattering (in the gold foil experiment), Ernest Rutherford developed an alternative model for the atom featuring a compact nucleus where the positive charge is concentrated. Thomson\'s model is popularly referred to as the \"plum pudding model\" with the notion that the electrons are distributed uniformly like raisins in a plum pudding. Neither Thomson nor his colleagues ever used this analogy. It seems to have been coined by popular science writers to make the model easier to understand for the layman. The analogy is perhaps misleading because Thomson likened the positive sphere to a liquid rather than a solid since he thought the electrons moved around in it. ## Significance Thomson\'s model was the first atomic model to describe an internal structure. Before this, atoms were simply the basic units of weight by which the chemical elements combined, and their only properties were valency and relative weight to hydrogen. The model had no properties which concerned physicists, such as electric charge, magnetic moment, volume, or absolute mass, and because of this some physicists had doubted atoms even existed. Thomson hypothesized that the quantity, arrangement, and motions of electrons in the atom could explain its physical and chemical properties, such as emission spectra, valencies, reactivity, and ionization. He was on the right track, though his approach was based on classical mechanics and he did not have the insight to incorporate quantized energy into it. ## Background Throughout the 19th century evidence from chemistry and statistical mechanics accumulated that matter was composed of atoms. The structure of the atom was discussed, and by the end of the century the leading model was the vortex theory of the atom, proposed by William Thomson (later Lord Kelvin) in 1867. By 1890, J.J. Thomson had his own version called the \"nebular atom\" hypothesis, in which atoms were composed of immaterial vortices and suggested similarities between the arrangement of vortices and periodic regularity found among the chemical elements. Thomson\'s discovery of the electron in 1897 changed his views. Thomson called them \"corpuscles\" (particles), but they were more commonly called \"electrons\", the name G. J. Stoney had coined for the \"fundamental unit quantity of electricity\" in 1891. However even late in 1899, few scientists believed in subatomic particles. Another emerging scientific theme of the 19th century was the discovery and study of radioactivity. Thomson discovered the electron by studying cathode rays, and in 1900 Henri Becquerel determined that the radiation from uranium, now called beta particles, had the same charge/mass ratio as cathode rays. These beta particles were believed to be electrons travelling at high speed. The particles were used by Thomson to probe atoms to find evidence for his atomic theory. The other form of radiation critical to this era of atomic models was alpha particles. Heavier and slower than beta particles, these were the key tool used by Rutherford to find evidence against Thomson\'s model. In addition to the emerging atomic theory, the electron, and radiation, the last element of history was the many studies of atomic spectra published in the late 19th century. Part of the attraction of the vortex model was its possible role in describing the spectral data as vibrational responses to electromagnetic radiation. Neither Thomson\'s model nor its successor, Rutherford\'s model, made progress towards understanding atomic spectra. That would have to wait until Niels Bohr built the first quantum-based atom model. ## Development Thomson\'s model was the first to assign a specific inner structure to an atom, though his earliest descriptions did not include mathematical formulas. From 1897 through 1913, Thomson proposed a series of increasingly detailed polyelectron models for the atom. His first versions were qualitative culminating in his 1906 paper and follow on summaries. Thomson\'s model changed over the course of its initial publication, finally becoming a model with much more mobility containing electrons revolving in the dense field of positive charge rather than a static structure. Thomson attempted unsuccessfully to reshape his model to account for some of the major spectral lines experimentally known for several elements. ### 1897 Corpuscles inside atoms {#corpuscles_inside_atoms} In a paper titled Cathode Rays, Thomson demonstrated that cathode rays are not light but made of negatively charged particles which he called corpuscles. He observed that cathode rays can be deflected by electric and magnetic fields, which does not happen with light rays. In a few paragraphs near the end of this long paper Thomson discusses the possibility that atoms were made of these corpuscles, calling them primordial atoms. Thomson believed that the intense electric field around the cathode caused the surrounding gas molecules to split up into their component corpuscles, thereby generating cathode rays. Thomson thus showed evidence that atoms were divisible, though he did not attempt to describe their structure at this point. Thomson notes that he was not the first scientist to propose that atoms are divisible, making reference to William Prout who in 1815 found that the atomic weights of various elements were multiples of hydrogen\'s atomic weight and hypothesised that all atoms were made of hydrogen atoms fused together. Prout\'s hypothesis was dismissed by chemists when by the 1830s it was found that some elements seemed to have a non-integer atomic weight---e.g. chlorine has an atomic weight of about 35.45. But the idea continued to intrigue scientists. The discrepancies were eventually explained with the discovery of isotopes in 1912. A few months after Thomson\'s paper appeared, George FitzGerald suggested that the corpuscle identified by Thomson from cathode rays and proposed as parts of an atom was a \"free electron\", as described by physicist Joseph Larmor and Hendrik Lorentz. While Thomson did not adopt the terminology, the connection convinced other scientists that cathode rays were particles, an important step in their eventual acceptance of an atomic model based on sub-atomic particles. In 1899 Thomson reiterated his atomic model in a paper that showed that negative electricity created by ultraviolet light landing on a metal (known now as the photoelectric effect) has the same mass-to-charge ratio as cathode rays; then he applied his previous method for determining the charge on ions to the negative electric particles created by ultraviolet light. He estimated that the electron\'s mass was 0.0014 times that of the hydrogen ion (as a fraction: `{{sfrac\|1\|714}}`{=mediawiki}). In the conclusion of this paper he writes: `{{blockquote\|I regard the atom as containing a large number of smaller bodies which I shall call corpuscles; these corpuscles are equal to each other; the mass of a corpuscle is the mass of the negative ion in a gas at low pressure, i.e. about 3 × 10<sup>−26</sup> of a gramme. In the normal atom, this assemblage of corpuscles forms a system which is electrically neutral. The negative effect is balanced by something which causes the space through which the corpuscles are spread to act as if it had a charge of positive electricity equal in amount to the sum of the negative charges on the corpuscles.}}`{=mediawiki} ### 1904 Mechanical model of the atom {#mechanical_model_of_the_atom} Thomson provided his first detailed description of the atom in his 1904 paper On the Structure of the Atom. Thomson starts with a short description of his model > \... the atoms of the elements consist of a number of negatively electrified corpuscles enclosed in a sphere of uniform positive electrification, \... Primarily focused on the electrons, Thomson adopted the positive sphere from Kelvin\'s atom model proposed a year earlier. He then gives a detailed mechanical analysis of such a system, distributing the electrons uniformly around a ring. The attraction of the positive electrification is balanced by the mutual repulsion of the electrons. His analysis focuses on stability, looking for cases where small changes in position are countered by restoring forces. After discussing his many formulae for stability he turned to analysing patterns in the number of electrons in various concentric rings of stable configurations. These regular patterns Thomson argued are analogous to the periodic law of chemistry behind the structure of the periodic table. This concept, that a model based on subatomic particles could account for chemical trends, encouraged interest in Thomson\'s model and influenced future work even if the details Thomson\'s electron assignments turned out to be incorrect. Thomson at this point believed that all the mass of the atom was carried by the electrons. This would mean that even a small atom would have to contain thousands of electrons, and the positive electrification that encapsulated them was without mass. ### 1905 lecture on electron arrangements {#lecture_on_electron_arrangements} In a lecture delivered to the Royal Institution of Great Britain in 1905, Thomson explained that it was too computationally difficult for him to calculate the movements of large numbers of electrons in the positive sphere, so he proposed a practical experiment. This involved magnetised pins pushed into cork discs and set afloat in a basin of water. The pins were oriented such that they repelled each other. Above the centre of the basin was suspended an electromagnet that attracted the pins. The equilibrium arrangement the pins took informed Thomson on what arrangements the electrons in an atom might take. For instance, he observed that while five pins would arrange themselves in a stable pentagon around the centre, six pins could not form a stable hexagon. Instead, one pin would move to the centre and the other five would form a pentagon around the centre pin, and this arrangement was stable. As he added more pins, they would arrange themselves in concentric rings around the centre. The experiment functioned in two dimensions instead of three, but Thomson inferred the electrons in the atom arranged themselves in concentric shells and they could move within these shells but did not move from one shell to another them except when electrons were added or subtracted from the atom. ### 1906 Estimating electrons per atom {#estimating_electrons_per_atom} Before 1906 Thomson considered the atomic weight to be due to the mass of the electrons (which he continued to call \"corpuscles\"). Based on his own estimates of the electron mass, an atom would need tens of thousands electrons to account for the mass. In 1906 he used three different methods, X-ray scattering, beta ray absorption, or optical properties of gases, to estimate that \"number of corpuscles is not greatly different from the atomic weight\". This reduced the number of electrons to tens or at most a couple of hundred and that in turn meant that the positive sphere in Thomson\'s model contained most of the mass of the atom. This meant that Thomson\'s mechanical stability work from 1904 and the comparison to the periodic table were no longer valid. Moreover, the alpha particle, so important to the next advance in atomic theory by Rutherford, would no longer be viewed as an atom containing thousands of electrons. In 1907, Thomson published The Corpuscular Theory of Matter which reviewed his ideas on the atom\'s structure and proposed further avenues of research. In Chapter 6, he further elaborates his experiment using magnetised pins in water, providing an expanded table. For instance, if 59 pins were placed in the pool, they would arrange themselves in concentric rings of the order 20-16-13-8-2 (from outermost to innermost). In Chapter 7, Thomson summarised his 1906 results on the number of electrons in an atom. He included one important correction: he replaced the beta-particle analysis with one based on the cathode ray experiments of August Becker, giving a result in better agreement with other approaches to the problem. Experiments by other scientists in this field had shown that atoms contain far fewer electrons than Thomson previously thought. Thomson now believed the number of electrons in an atom was a small multiple of its atomic weight: \"the number of corpuscles in an atom of any element is proportional to the atomic weight of the element --- it is a multiple, and not a large one, of the atomic weight of the element.\" This meant that almost all of the atom\'s mass had to be carried by the positive sphere, whatever it was made of. Thomson in this book estimated that a hydrogen atom is 1,700 times heavier than an electron (the current measurement is 1,837). Thomson noted that no scientist had yet found a positively charged particle smaller than a hydrogen ion. He also wrote that the positive charge of an atom is a multiple of a basic unit of positive charge, equal to the negative charge of an electron. Thomson refused to jump to the conclusion that the basic unit of positive charge has a mass equal to that of the hydrogen ion, arguing that scientists first had to know how many electrons an atom contains. For all he could tell, a hydrogen ion might still contain a few electrons---perhaps two electrons and three units of positive charge. ### 1910 Multiple scattering {#multiple_scattering} Thomson\'s difficulty with beta scattering in 1906 lead him to renewed interest in the topic. He encouraged J. Arnold Crowther to experiment with beta scattering through thin foils and, in 1910, Thomson produced a new theory of beta scattering. The two innovations in this paper was the introduction of scattering from the positive sphere of the atom and analysis that multiple or compound scattering was critical to the final results. This theory and Crowther\'s experimental results would be confronted by Rutherford\'s theory and Geiger and Mardsen new experiments with alpha particles. Another innovation in Thomson\'s 1910 paper was that he modelled how an atom might deflect an incoming beta particle if the positive charge of the atom existed in discrete units of equal but arbitrary size, spread evenly throughout the atom, separated by empty space, with each unit having a positive charge equal to the electron\'s negative charge. Thomson therefore came close to deducing the existence of the proton, which was something Rutherford eventually did. In Rutherford\'s model of the atom, the protons are clustered in a very small nucleus, but in Thomson\'s alternative model, the positive units were spread throughout the atom. ## Thomson\'s 1910 beta scattering model {#thomsons_1910_beta_scattering_model} In his 1910 paper \"On the Scattering of rapidly moving Electrified Particles\", Thomson presented equations that modelled how beta particles scatter in a collision with an atom. His work was based on beta scattering studies by James Crowther. ### Partial deflection by the positive sphere {#partial_deflection_by_the_positive_sphere} Thomson typically assumed the positive charge in the atom was uniformly distributed throughout its volume, encapsulating the electrons. In his 1910 paper, Thomson presented the following equation which isolated the effect of this positive sphere: $\bar\theta_2 = \frac{\pi}{4} \cdot \frac{k q_\text{e} q_\text{g}}{m v^2 R}$ where k is the Coulomb constant, q~e~ is the charge of the beta particle, q~g~ is the charge of the positive sphere, m is the mass of the beta particle, and R is the radius of the sphere. Because the atom is many thousands of times heavier than the beta particle, no correction for recoil is needed. Thomson did not explain how this equation was developed, but the historian John L. Heilbron provided an educated guess he called a \"straight-line\" approximation. Consider a beta particle passing through the positive sphere with its initial trajectory at a lateral distance b from the centre. The path is assumed to have a very small deflection and therefore is treated here as a straight line. center\\|thumb\\|upright=2\\|Diagram is not to scale. The beta particle\'s deviation is in fact so small, the path is practically a straight line. Inside a sphere of uniformly distributed positive charge the force exerted on the beta particle at any point along its path through the sphere would be directed along the radius `{{mvar \|r}}`{=mediawiki} with magnitude: $F = \frac{k q_\text{e} q_\text{g}}{r^2} \cdot \frac{r^3}{R^3}$ The component of force perpendicular to the trajectory and thus deflecting the path of the particle would be: $F_\text{y} = \frac{k q_\text{e} q_\text{g}}{r^2} \cdot \frac{r^3}{R^3} \cdot \cos\varphi = \frac{b k q_\text{e} q_\text{g}}{R^3}$ The lateral change in momentum p~y~ is therefore $\Delta p_\text{y} = F_\text{y} t =\frac{b k q_\text{e} q_\text{g}}{R^3} \cdot \frac{L}{v}$ The resulting angular deflection, $\theta_2$, is given by $\tan\theta_2 = \frac{\Delta p_\text{y}}{p_\text{x}} = \frac{b k q_\text{e} q_\text{g}}{R^3} \cdot \frac{L}{v} \cdot \frac{1}{mv}$ where p~x~ is the average horizontal momentum taken to be equal to the incoming momentum. Since we already know the deflection is very small, we can treat $\tan\theta_2$ as being equal to $\theta_2$. To find the average deflection angle $\bar\theta_2$, the angle for each value of b and the corresponding L are added across the face sphere, then divided by the cross-section area. $L=2\sqrt{R^2 -b^2}$ per Pythagorean theorem. $\bar\theta_2 = \frac{1}{\pi R^2} \int_0^R \frac{b k q_\text{e} q_\text{g}}{R^3} \cdot \frac{2\sqrt{R^2 - b^2}}{v} \cdot \frac{1}{mv} \cdot 2\pi b \cdot \mathrm{d}b$ $= \frac{\pi}{4} \cdot \frac{k q_\text{e} q_\text{g}}{mv^2R}$ This matches Thomson\'s formula in his 1910 paper. ### Partial deflection by the electrons {#partial_deflection_by_the_electrons} Thomson modelled the collisions between a beta particle and the electrons of an atom by calculating the deflection of one collision then multiplying by a factor for the number of collisions as the particle crosses the atom. center\\|thumb\\|upright=2 For the electrons within an arbitrary distance s of the beta particle\'s path, their mean distance will be `{{sfrac\|''s''\|2}}`{=mediawiki}. Therefore, the average deflection per electron will be $2 \arctan \frac{k q_\text{e} q_\text{e}}{mv^2 \tfrac{s}{2}} \approx \frac{4 k q_\text{e} q_\text{e}}{m v^2 s}$ where q~e~ is the elementary charge, k is the Coulomb constant, m and v are the mass and velocity of the beta particle. The factor for the number of collisions was known to be the square root of the number of possible electrons along path. The number of electrons depends upon the density of electrons along the particle path times the path length L. The net deflection caused by all the electrons within this arbitrary cylinder of effect around the beta particle\'s path is $\theta_1 = \frac{4k q_\text{e} q_\text{e}}{mv^2 s} \cdot \sqrt{N_0 \pi s^2 L}$ where N~0~ is the number of electrons per unit volume and $\pi s^2 L$ is the volume of this cylinder. Since Thomson calculated the deflection would be very small, he treats L as a straight line. Therefore $L = 2\sqrt{R^2 - b^2}$ where b is the distance of this chord from the centre. The mean of $\sqrt{L}$ is given by the integral $\frac{1}{\pi R^2} \int_0^R \sqrt{2 \sqrt{R^2 - b^2}} \cdot 2\pi b \cdot \mathrm{d}b = \frac{4}{5} \sqrt{2R}$ We can now replace $\sqrt{L}$ in the equation for $\theta_1$ to obtain the mean deflection $\bar{\theta}_1$: $\bar{\theta}_1 = \frac{4k q_\text{e} q_\text{e}}{mv^2 s} \cdot \sqrt{N_0 \pi s^2} \cdot \frac{4}{5} \sqrt{2R}$ $= \frac{16}{5} \cdot \frac{k q_\text{e} q_\text{e}}{m v^2} \cdot \frac{1}{R} \cdot \sqrt{\frac{3N}{2}}$ where N is the number of electrons in the atom, equal to $N_0 \tfrac{4}{3} \pi R^3$. ### Deflection by the positive charge in discrete units {#deflection_by_the_positive_charge_in_discrete_units} In his 1910 paper, Thomson proposed an alternative model in which the positive charge exists in discrete units separated by empty space, with those units being evenly distributed throughout the atom\'s volume. center\\|thumb\\|upright=2 In this concept, the average scattering angle of the beta particle is given by: $\bar{\theta}_2 = \frac{16}{5} \cdot \frac{k q_\text{e} q_\text{e}}{m v^2} \cdot \frac{1}{R} \cdot \sqrt{\frac{3N}{2}} \sqrt{1 - \left (1 - \frac{\pi}{8} \right ) \sqrt{\sigma}}$ where σ is the ratio of the volume occupied by the positive charge to the volume of the whole atom. Thomson did not explain how he arrived at this equation. ### Net deflection {#net_deflection} To find the combined effect of the positive charge and the electrons on the beta particle\'s path, Thomson provided the following equation: $\bar{\theta} = \sqrt{\bar{\theta}_1^2 + \bar{\theta}_2^2}$ ## Demise of the plum pudding model {#demise_of_the_plum_pudding_model} upright=1.5\\|thumb\\|The results of the Rutherford scattering experiments and their implications for atomic theory\ Left: Had Thomson\'s model been correct, all the alpha particles should have passed through the foil with minimal scattering.\ Right: What Geiger and Marsden observed was that a small fraction of the alpha particles experienced strong deflection. Thomson probed the structure of atoms through beta particle scattering, whereas his former student Ernest Rutherford was interested in alpha particle scattering. Beta particles are electrons emitted by radioactive decay, whereas alpha particles are essentially helium atoms, also emitted in process of decay. Alpha particles have considerably more momentum than beta particles and Rutherford found that matter scatters alpha particles in ways that Thomson\'s plum pudding model could not predict. Between 1908 and 1913, Ernest Rutherford, Hans Geiger, and Ernest Marsden collaborated on a series of experiments in which they bombarded thin metal foils with a beam of alpha particles and measured the intensity versus scattering angle of the particles. They found that the metal foil could scatter alpha particles by more than 90°. This should not have been possible according to the Thomson model: the scattering into large angles should have been negligible. The odds of a beta particle being scattered by more than 90° under such circumstances is astronomically small, and since alpha particles typically have much more momentum than beta particles, their deflection should be smaller still. The Thomson models simply could not produce electrostatic forces of sufficient strength to cause such large deflection. The charges in the Thomson model were too diffuse. This led Rutherford to discard the Thomson for a new model where the positive charge of the atom is concentrated in a tiny nucleus. Rutherford went on to make more compelling discoveries. In Thomson\'s model, the positive charge sphere was just an abstract component, but Rutherford found something concrete to attribute the positive charge to: particles he dubbed \"protons\". Whereas Thomson believed that the electron count was roughly correlated to the atomic weight, Rutherford showed that (in a neutral atom) it is exactly equal to the atomic number. Thomson hypothesised that the arrangement of the electrons in the atom somehow determined the spectral lines of a chemical element. He was on the right track, but it had nothing to do with how atoms circulated in a sphere of positive charge. Scientists eventually discovered that it had to do with how electrons absorb and release energy in discrete quantities, moving through energy levels which correspond to emission and absorption spectra. Thomson had not incorporated quantum mechanics into his atomic model, which at the time was a very new field of physics. Niels Bohr and Erwin Schroedinger later incorporated quantum mechanics into the atomic model. ### Rutherford\'s nuclear model {#rutherfords_nuclear_model} Rutherford\'s 1911 paper on alpha particle scattering showed that Thomson\'s scattering model could not explain the large angle scattering and it showed that multiple scattering was not necessary to explain the data. However, in the years immediately following its publication few scientists took note. The scattering model predictions were not considered definitive evidence against Thomson\'s plum pudding model. Thomson and Rutherford had pioneered scattering as a technique to probe atoms, its reliability and value were unproven. Before Rutherford\'s paper the alpha particle was considered an atom, not a compact mass. It was not clear why it should be a good probe. Moreover, Rutherford\'s paper did not discuss the atomic electrons vital to practical problems like chemistry or atomic spectroscopy. Rutherford\'s nuclear model would only become widely accepted after the work of Niels Bohr. ## Mathematical Thomson problem {#mathematical_thomson_problem} The Thomson problem in mathematics seeks the optimal distribution of equal point charges on the surface of a sphere. Unlike the original Thomson atomic model, the sphere in this purely mathematical model does not have a charge, and this causes all the point charges to move to the surface of the sphere by their mutual repulsion. There is still no general solution to Thomson\'s original problem of how electrons arrange themselves within a sphere of positive charge. ## Origin of the nickname {#origin_of_the_nickname} The first known writer to compare Thomson\'s model to a plum pudding was an anonymous reporter in an article for the British pharmaceutical magazine The Chemist and Druggist in August 1906. The analogy was never used by Thomson nor his colleagues. It seems to have been coined by popular science writers to make the model easier to understand for the layman.	2025-06-20T00:00:00
2,853	Aberdeen Bestiary	The *Aberdeen Bestiary* (Aberdeen University Library, Univ Lib. MS 24) is a 12th-century English illuminated manuscript bestiary that was first listed in 1542 in the inventory of the Old Royal Library at the Palace of Westminster. Due to similarities, it is often considered to be the \"sister\" manuscript of the Ashmole Bestiary. The connection between the ancient Greek didactic text Physiologus and similar bestiary manuscripts is also often noted. Information about the manuscript\'s origins and patrons are circumstantial, although the manuscript most likely originated from the 13th century and was owned by a wealthy ecclesiastical patron from northern or southern England. Currently, the Aberdeen Bestiary resides in the Aberdeen University Library in Scotland. ## History The Aberdeen Bestiary and the Ashmole Bestiary are considered by Xenia Muratova, a professor of Art History, to be \"the work of different artists belonging to the same artistic milieu.\" Due to their \"striking similarities\" they are often compared and described by scholars as being \"sister manuscripts.\" The medievalist scholar M. R. James considered the Aberdeen Bestiary \'\'a replica of Ashmole 1511\" a view echoed by many other art historians. ### Provenance The original patron of both the Aberdeen and Ashmole Bestiary was considered to be a high-ranking member of society such as a prince, king or another high ranking church official or monastery. However, since the section related to monastery life that was commonly depicted within the Aviarium manuscript was missing the original patron remains uncertain but it appears less likely to be a church member. The Aberdeen Bestiary was kept in Church and monastic settings for a majority of its history. However at some point it entered into the English royal collections library. The royal Westminster Library shelf stamp of Henry VIII of England is stamped on the side of the bestiary. How King Henry acquired the manuscript remains unknown although it was probably taken from a monastery. The manuscript appears to have been well-read by the family based on the amount of reading wear on the edges of the pages. Around the time King James of Scotland became the King of England the bestiary was passed along to Marischal College in Aberdeen, Scotland. The manuscript is in fragmented condition as many illuminations on folios were removed individually as miniatures likely not for monetary but possibly for personal reasons. The manuscript currently is in the Aberdeen Library in Scotland where it has remained since 1542. ## Description ### Materials The Aberdeen bestiary is a gilded, decorated manuscript featuring large miniatures and some of the finest pigment, parchment and gold leaf from its time. Some portions of the manuscript such as folio eight recto even feature tarnished silver leaf. The original patron was wealthy enough to afford such materials so that the artists and scribes could enjoy creative freedom while creating the manuscripts. The artists were professionally trained and experimented with new techniques - such as heavy washes mixed with light washes and dark thick lines and use of contrasting color. The aqua color that is in the Aberdeen Bestiary is not present in the Ashmole Bestiary. The Aberdeen manuscript is loaded with filigree flora design and champie style gold leaf initials. Canterbury is considered to be the original location of manufacture as the location was well known for manufacturing high-end luxury books during the thirteen century. Its similarities with the Canterbury Paris Psalter tree style also further draws evidence of this relation. ### Style The craftsmanship of both Ashmole and Aberdeen bestiary suggest similar artists and scribes. Both the Ashmole and Aberdeen bestiary were probably made within 10 years of each other due to their stylistic and material similarities and the fact that both are crafted with the finest materials of their time. Stylistically both manuscripts are very similar but the Aberdeen has figures that are both more voluminous and less energetic than those of the Ashmole Bestiary. The color usage has been suggested as potentially Biblical in meaning as color usage had different interpretations in the early 13th century. The overall style of the human figures as well as color usage is very reminiscent of Roman mosaic art especially with the attention to detail in the drapery. Circles and ovals semi-realistically depict highlights throughout the manuscript. The way that animals are shaded in a Romanesque fashion with the use of bands to depict volume and form, which is similar to an earlier 12th-century Bury Bible made at Bury St.Edmunds. This Bestiary also shows stylistic similarities with the Paris Psalters of Canterbury. The Aviary section is similar to the Aviariium which is a well-known 12th century monastic text. The deviation from traditional color usage can be seen in the tiger, satyr, and unicorn folios as well as many other folios. The satyr in the Aberdeen Bestiary when compared to the satyr section of the slightly older Worksop bestiary is almost identical. There are small color notes in the Aberdeen Bestiary that are often seen in similar manuscripts dating between 1175 and 1250 which help indicate that it was made near the year 1200 or 1210. These notes are similar to many other side notes written on the sides of pages throughout the manuscript and were probably by the painter to remind himself of special circumstances, these note occur irregularly throughout the text. ### Illuminations Folio page 1 to 3 recto depicts the Genesis 1:1-25 which is represented with a large full page illumination Biblical Creation scene in the manuscript. Folio 5 recto shows Adam, a large figure surrounded by gold leaf and towering over others, with the theme of \'Adam naming the animals\' - this starts the compilation of the bestiary portion within the manuscript. Folio 5 verso depicts quadrupeds, livestock, wild beasts, and the concept of the herd. Folio 7 to 18 recto depicts large cats and other beasts such as wolves, foxes and dogs. Many pages from the start of the manuscript\'s bestiary section such as 11 verso featuring a hyena shows small pin holes which were likely used to map out and copy artwork to a new manuscript. Folio 20 verso to 28 recto depicts livestock such as sheep, horses, and goats. Small animals like cats and mice are depicted on folio 24 to 25. Pages 25 recto to 63 recto feature depictions of birds and folio 64 recto to 80 recto depicts reptiles, worms and fish. 77 recto to 91 verso depicts trees and plants and other elements of nature such as the nature of man. The end folios of the manuscript from 93 recto to 100 recto depicts the nature of stones and rocks. Seventeen of the Aberdeen manuscript pages are pricked for transfer in a process called pouncing such as clearly seen in the hyena folio as well as folio 3 recto and 3 verso depicting Genesis 1:26-1:28, 31, 1:1-2. The pricking must have been done shortly after the creation of the Adam and Eve folio pages since there is not damage done to nearby pages. Other pages used for pouncing include folio 7 recto to 18 verso which is the beginning of the beasts portion of the manuscript and likely depicted a lions as well as other big cats such as leopards, panthers and their characteristic as well as other large wild and domesticated beasts. ### Missing Folios {#missing_folios} On folio 6 recto there was likely intended to be a depiction of a lion as in the Ashmole bestiary, but in this instance the pages were left blank although there are markings of margin lines. In comparison to the Ashmole bestiary, on 9 verso some leaves are missing which should have likely contained imagery of the antelope (Antalops), unicorn (Unicornis), lynx (Lynx), griffin (Gryps), part of elephant (Elephans). Near folio 21 verso two illuminations of the ox (Bos), camel (Camelus), dromedary (Dromedarius), ass (Asinus), onager (Onager) and part of horse (Equus) are also assumed to be missing. Also missing from folio 15 recto on are some leaves which should have contained crocodile (Crocodilus), manticore (Mantichora) and part of parandrus (Parandrus). These missing folios are assumed from comparisons between the Ashmole and other related bestiaries. ## Contents - Folio 1 recto : Genesis creation narrative of heaven and earth (Genesis, 1: 1--5). (Full page) - Folio 1 verso: Creation of the waters and the firmament (Genesis, 1: 6--8) - Folio 2 recto : Creation of the birds and fish (Genesis, 1: 20--23) - Folio 2 verso : Creation of the animals (Genesis, 1: 24--25) - Folio 3 recto : Creation of man (Genesis, 1: 26--28, 31; 2: 1--2) - Folio 5 recto : Adam names the animals (Isidore of Seville, Etymologiae, Book XII, i, 1--2) - Folio 5 verso : Animal (Animal) (Isidore of Seville, Etymologiae, Book XII, i, 3) - Folio 5 verso : Quadruped (Quadrupes) (Isidore of Seville, Etymologiae, Book XII, i, 4) - Folio 5 verso : Livestock (Pecus) (Isidore of Seville, Etymologiae, Book XII, i, 5--6) - Folio 5 verso : Beast of burden (Iumentum) (Isidore of Seville, Etymologiae, Book XII, i, 7) - Folio 5 verso : Herd (Armentum) (Isidore of Seville, Etymologiae, Book XII, i, 8) ### Beasts (Bestiae) {#beasts_bestiae} - Folio 7 recto : Lion (Leo) (Physiologus, Chapter 1; Isidore of Seville, Etymologiae, Book XII, ii, 3--6) - Folio 8 recto : Tiger (Tigris) (Isidore of Seville, Etymologiae, Book XII, ii, 7) - Folio 8 verso : Pard (Pard) (Isidore of Seville, Etymologiae, Book XII, ii, 10--11) - Folio 9 recto : Panther (Panther) (Physiologus, Chapter 16; Isidore of Seville, Etymologiae, Book XII, ii, 8--9) - Folio 10 recto : Elephant (Elephans) (Isidore of Seville, Etymologiae, Book XII, ii, 14; Physiologus, Chapter 43; Ambrose, Hexaemeron, Book VI, 35; Solinus, [Collectanea rerum memorabilium](http://www.thelatinlibrary.com/solinus5.html), xxv, 1--7) - Folio 11 recto : Beaver (Castor) - Folio 11 recto : Ibex (Ibex) (Hugh of Fouilloy, II, 15) - Folio 11 verso : Hyena (Yena) (Physiologus, Chapter 24; Solinus, Collectanea rerum memorabilium, xxvii, 23--24) - Folio 12 recto : Crocotta (Crocotta) (Solinus, Collectanea rerum memorabilium, xxvii, 26) - Folio 12 recto : Bonnacon (Bonnacon) (Solinus, Collectanea rerum memorabilium, xl, 10--11) - Folio 12 verso : Ape (Simia) - Folio 13 recto : Satyr (Satyrs) - Folio 13 recto : Deer (Cervus) - Folio 14 recto : Goat (Caper) - Folio 14 verso : Wild goat (Caprea) - Folio 15 recto : Monoceros (Monoceros) (Solinus, [Collectanea rerum memorabilium](http://www.thelatinlibrary.com/solinus5.html), lii, 39--40) - Folio 15 recto : Bear (Ursus) - Folio 15 verso : Leucrota (Leucrota) (Solinus, Collectanea rerum memorabilium, lii, 34) - Folio 16 recto : Parandrus (Parandrus) (Solinus, Collectanea rerum memorabilium, xxx, 25) - Folio 16 recto : Fox (Vulpes) - Folio 16 verso : Yale (Eale) (Solinus, Collectanea rerum memorabilium, lii, 35) - Folio 16 verso : Wolf (Lupus) - Folio 18 recto : Dog (Canis) ### Livestock (Pecora) {#livestock_pecora} - Folio 20 verso : Sheep (Ovis) (Isidore of Seville, Etymologiae, Book XII, i, 9; Ambrose, Hexaemeron, Book VI, 20) - Folio 21 recto : Wether (Vervex) (Isidore of Seville, Etymologiae, Book XII, i, 10) - Folio 21 recto : Ram (Aries) (Isidore of Seville, Etymologiae, Book XII, i, 11) - Folio 21 recto : Lamb (Agnus) (Isidore of Seville, Etymologiae, Book XII, i, 12; Ambrose, Hexaemeron, Book VI, 28) - Folio 21 recto : He-goat (Hircus) (Isidore of Seville, Etymologiae, Book XII, i, 14) - Folio 21 verso : Kid (Hedus) (Isidore of Seville, Etymologiae, Book XII, i, 13) - Folio 21 verso : Boar (Aper) (Isidore of Seville, Etymologiae, Book XII, i, 27) - Folio 21 verso : Bullock (Iuvencus) (Isidore of Seville, Etymologiae, Book XII, i, 28) - Folio 21 verso : Bull (Taurus) (Isidore of Seville, Etymologiae, Book XII, i, 29) - Folio 22 recto : Horse (Equus) (Isidore of Seville, Etymologiae, Book XII, i, 41--56; Hugh of Fouilloy, III, xxiii) - Folio 23 recto : Mule (Mulus) (Isidore of Seville, Etymologiae, Book XII, i, 57--60) ### Small animals (Minuta animala) {#small_animals_minuta_animala} - Folio 23 verso : Cat (Musio) (Isidore of Seville, Etymologiae, Book XII, ii, 38) - Folio 23 verso : Mouse (Mus) (Isidore of Seville, Etymologiae, Book XII, iii, 1) - Folio 23 verso : Weasel (Mustela) (Isidore of Seville, Etymologiae, Book XII, iii, 2; Physiologus, Chapter 21) - Folio 24 recto : Mole (Talpa) (Isidore of Seville, Etymologiae, Book XII, iii, 5) - Folio 24 recto : Hedgehog (Ericius) (Isidore of Seville, Etymologiae, Book XII, iii, 7; Ambrose, Hexaemeron, VI, 20) - Folio 24 verso : Ant (Formica) (Physiologus, 12; Ambrose, Hexaemeron, Book VI, 16, 20) ### Birds (Aves) {#birds_aves} - Folio 25 recto : Bird (Avis) - Folio 25 verso : Dove (Columba) - Folio 26 recto : Dove and hawk (Columba et Accipiter) - Folio 26 verso : Dove (Columba) - Folio 29 verso : North wind and South wind (Aquilo et Auster ventus) - Folio 30 recto : Hawk (Accipiter) - Folio 31 recto : Turtle dove (Turtur) - Folio 32 verso : Palm tree (Palma) - Folio 33 verso : Cedar (Cedrus) - Folio 34 verso : Pelican (Pellicanus) - Orange and blue - Folio 35 verso : Night heron (Nicticorax) - Folio 36 recto : Hoopoe (Epops) - Folio 36 verso : Magpie (Pica) - Folio 37 recto : Raven (Corvus) - Folio 38 verso : Cock (Gallus) - Folio 41 recto : Ostrich (Strutio) - Folio 44 recto : Vulture (Vultur) - Folio 45 verso : Crane (Grus) - Folio 46 verso : Kite (Milvus) - Folio 46 verso : Parrot (Psitacus) - Folio 47 recto : Ibis (Ibis) - Folio 47 verso : Swallow (Yrundo) - Folio 48 verso : Stork (Ciconia) - Folio 49 verso : Blackbird (Merula) - Folio 50 recto : Eagle-owl (Bubo) - Folio 50 verso : Hoopoe (Hupupa) - Folio 51 recto : Little owl (Noctua) - Folio 51 recto : Bat (Vespertilio) - Folio 51 verso : Jay (Gragulus) - Folio 52 verso : Nightingale (Lucinia) - Folio 53 recto : Goose (Anser) - Folio 53 verso : Heron (Ardea) - Folio 54 recto : Partridge (Perdix) - Folio 54 verso : Halcyon (Alcyon) - Folio 55 recto : Coot (Fulica) - Folio 55 recto : Phoenix (Fenix) - Folio 56 verso : Caladrius (Caladrius) - Folio 57 verso : Quail (Coturnix) - Folio 58 recto : Crow (Cornix) - Folio 58 verso : Swan (Cignus) - Folio 59 recto : Duck (Anas) - Folio 59 verso : Peacock (Pavo) - Folio 61 recto : Eagle (Aquila) - Folio 63 recto : Bee (Apis) ### Snakes and Reptiles (Serpentes) {#snakes_and_reptiles_serpentes} - Folio 64 verso : Peridexion tree (Perindens) - Folio 65 verso : Snake (Serpens) - Folio 65 verso : Dragon (Draco) - Folio 66 recto : Basilisk (Basiliscus) - Folio 66 verso : Regulus (Regulus) - Folio 66 verso : Viper (Vipera) - Folio 67 verso : Asp (Aspis) - Folio 68 verso : Scitalis (Scitalis) - Folio 68 verso : Amphisbaena (Anphivena) - Folio 68 verso : Hydrus (Ydrus) - Folio 69 recto : Boa (Boa) - Folio 69 recto : Iaculus (Iaculus) - Folio 69 verso : Siren (Siren) - Folio 69 verso : Seps (Seps) - Folio 69 verso : Dipsa (Dipsa) - Folio 69 verso : Lizard (Lacertus) - Folio 69 verso : Salamander (Salamandra) - Folio 70 recto : Saura (Saura) - Folio 70 verso : Newt (Stellio) - Folio 71 recto : Of the nature of Snakes (De natura serpentium) ### Worms (Vermes) {#worms_vermes} - Folio 72 recto : Worms (Vermis) ### Fish (Pisces) {#fish_pisces} - Folio 72 verso : Fish (Piscis) - Folio 73 recto : Whale (Balena) - Folio 73 recto : Serra (Serra) - Folio 73 recto : Dolphin (Delphinus) - Folio 73 verso : Sea-pig (Porcus marinus) - Folio 73 verso : Crocodile (Crocodrillus) - Folio 73 verso : Mullet (Mullus) - Folio 74 recto : Fish (Piscis) ### Trees and Plants (Arbories) {#trees_and_plants_arbories} - Folio 77 verso : Tree (Arbor) - Folio 78 verso : Fig (Ficus) - Folio 79 recto : Again of trees (Item de arboribus) - Folio 79 recto : Mulberry - Folio 79 recto : Sycamore - Folio 79 recto : Hazel - Folio 79 recto : Nuts - Folio 79 recto : Almond - Folio 79 recto : Chestnut - Folio 79 recto : Oak - Folio 79 verso : Beech - Folio 79 verso : Carob - Folio 79 verso : Pistachio - Folio 79 verso : Pitch pine - Folio 79 verso : Pine - Folio 79 verso : Fir - Folio 79 verso : Cedar - Folio 80 recto : Cypress - Folio 80 recto : Juniper - Folio 80 recto : Plane - Folio 80 recto : Oak - Folio 80 recto : Ash - Folio 80 recto : Alder - Folio 80 verso : Elm - Folio 80 verso : Poplar - Folio 80 verso : Willow - Folio 80 verso : Osier - Folio 80 verso : Box ### Nature of Man (Natura hominis) {#nature_of_man_natura_hominis} - Folio 80 verso : Isidorus on the nature of man (Ysidorus de natura hominis) - Folio 89 recto : Isidorus on the parts of man\'s body (Ysidorus de membris hominis) - Folio 91 recto : Of the age of man (De etate hominis) ### Stones (Lapides) {#stones_lapides} - Folio 93 verso : Fire-bearing stone (Lapis ignifer) - Folio 94 verso : Adamas stone (Lapis adamas) - Folio 96 recto : Myrmecoleon (Mermecoleon) - Folio 96 verso : Verse (Versus) - Folio 97 recto : Stone in the foundation of the wall (Lapis in fundamento muri) - Folio 97 recto : The first stone, Jasper - Folio 97 recto : The second stone, Sapphire - Folio 97 recto : The third stone, Chalcedony - Folio 97 verso : The fourth stone, Smaragdus - Folio 98 recto : The fifth stone, Sardonyx - Folio 98 recto : The sixth stone, Sard - Folio 98 verso : The seventh stone, Chrysolite - Folio 98 verso : The eighth stone, Beryl - Folio 99 recto : The ninth stone, Topaz - Folio 99 verso : The tenth stone, Chrysoprase - Folio 99 verso : The eleventh stone, Hyacinth - Folio 100 recto : The twelfth stone, Amethyst - Folio 100 recto : Of stones and what they can do (De effectu lapidum) ## Gallery <File:Phoenix> detail from Aberdeen Bestiary.jpg\\|alt=Folio 56 Recto - Phoenix (detail)\\|Folio 56 Recto - Phoenix (detail) <File:Aberdeen> Bestiary Basilisk.jpg\\|alt=Folio 66 Recto - Basilisk (Detail)\\|Folio 66 Recto - Basilisk (detail) <File:Beaver> (Aberdeen Bestiary).jpg\\|alt=Folio 11 Recto - Beaver (Detail)\\|Folio 11 Recto - Beaver (detail) <File:Hyena> bestiary.jpg\\|alt=Folio 11 Verso - Hyena (Detail)\\|Folio 11 Verso - Hyena (detail) <File:AberdeenBestiaryFolio065vDragonDetail.jpg%7Calt=Folio> 65 Verso - Dragon (detail)\\|Folio 65 Verso - Dragon (detail) <File:Vultures> in Aberdeen Bestiary.jpg\\|alt=Folio 44 Recto - Vulture (detail)\\|Folio 44 Recto - Vulture (detail) <File:Aberdeen> Bestiary - Owl.JPG\\|alt=Folio 51 Recto - Little Owl (detail)\\|Folio 51 Recto - Little Owl (detail) <File:Bubo> owl aberdeen bestiary.png\\|alt=Folio 50 - Eagle Owl (detail)\\|Folio 50 - Eagle Owl (detail) <File:Aberdeen> ram.jpg\\|alt=Folio 21 Recto - Ram/Aries (Detail)\\|Folio 21 Recto - Ram/Aries (detail) <File:AberdeenBestiaryFolio008vLeopardDetail.jpg%7Calt=Folio> 8 Verso - Leopard (detail)\\|Folio 8 Verso - Leopard (detail) <File:AberdeenBestiaryFolio008rTigerDetail.jpg%7Calt=Folio> 8 Recto - Tiger\\|Folio 8 Recto - Tiger <File:F13r-aberdeen-best.jpg%7Calt=Folio> 13 Recto - Satyr (detail)\\|Folio 13 Recto - Satyr (detail) <File:F15r-aberdeen-best-detail.jpg%7Calt=Folio> 15 Recto - Monoceros (detail)\\|Folio 15 Recto - Monoceros (detail) <File:Wolf> sneak.jpg\\|alt=Folio 16 Verso - Wolf (detail)\\|Folio 16 Verso - Wolf (detail) <File:AberdeenBestiaryFolio005rAdamNamesAnimalsDetail.jpg%7Calt=Folio> 5 Recto - Adam (detail)\\|Folio 5 Recto - Adam (detail)	2025-06-20T00:00:00
2,856	Latin American Integration Association	The Latin American Integration Association / Asociación Latinoamericana de Integración / Associação Latino-Americana de Integração (LAIA / ALADI) is an international and regional scope organization. It was created on 12 August 1980 by the 1980 Montevideo Treaty, replacing the Latin American Free Trade Association (LAFTA/ALALC). Currently, it has 13 member countries, and any of the Latin American States may apply for accession. ## Objectives The development of the integration process developed within the framework of the ALADI aims at promoting the harmonious and balanced socio-economic development of the region, and its long-term objective is the gradual and progressive establishment of a Latin-American single market. ## Basic functions {#basic_functions} - Promotion and regulation of reciprocal trade - Economic complementation - Development of economic cooperation actions contributing to the markets extension. ## General principles {#general_principles} - Pluralism in political and economic matters; - Progressive convergence of partial actions for the establishment of a Latin-American Common Market; - Flexibility; - Differential treatments based on the development level of the member countries; and - Multiple forms of trade agreements. ## Integration mechanisms {#integration_mechanisms} The ALADI promotes the establishment of an area of economic preferences within the region, in order to create a Latin-American common market, through three mechanisms: - A Regional Tariff Preference applied to goods from the member countries compared to tariffs in-force for third countries. - Regional Scope Agreements, those in which all member countries participate. - Partial Scope Agreements, those wherein two or more countries of the area participate. The Relatively Less Economically Developed Countries of the region (Bolivia, Ecuador and Paraguay) benefit from a preferential system, through the lists of markets opening offered by the countries in favor of the Relatively Less Economically Developed Countries; special programs of cooperation (business rounds, pre-investment, financing, technological support); and countervailing measures in favor of the land-locked countries, the full participation of such countries in the integration process is sought. The ALADI includes in its legal structure the strongest sub-regional, plurilateral and bilateral integration agreements arising in growing numbers in the continent. As a result, the ALADI -- as an institutional and legal framework or "umbrella" of the regional integration- develops actions in order to support and foster these efforts for the progressive establishment of a common economic space. ## Member states {#member_states} State Members Join Date Population Land Surface Exclusive Economic Zone Platform Capital City --------------- ----------- ------------ -------------- ------------------------- ---------- ------------------- Founder km^2^ km^2^ km^2^ Buenos Aires Founder km^2^ Landlocked Sucre & La Paz Founder km^2^ km^2^ km^2^ Brasília Founder km^2^ km^2^ km^2^ Santiago de Chile Founder km^2^ km^2^ km^2^ Bogotá 1999 km^2^ km^2^ km^2^ Havana Founder km^2^ km^2^ km^2^ Quito Founder km^2^ km^2^ km^2^ Mexico City Founder km^2^ Landlocked Asunción 2011 km^2^ km^2^ km^2^ Panama City Founder km^2^ km^2^ km^2^ Lima Founder km^2^ km^2^ km^2^ Montevideo Founder km^2^ km^2^ km^2^ Caracas Total: km^2^ km^2^ km^2^ ## Accession of other Latin American countries {#accession_of_other_latin_american_countries} The 1980 Montevideo Treaty is open to the accession of any Latin-American country. On 26 August 1999, the first accession to the 1980 Montevideo Treaty was executed, with the incorporation of the Republic of Cuba as a member country of the ALADI. On 10 May 2012, the Republic of Panama became the thirteenth member country of the ALADI. Likewise, the accession of the Republic of Nicaragua was accepted in the Sixteenth Meeting of the Council of Ministers (Resolution 75 (XVI)), held on 11 August 2011. Currently, Nicaragua moves towards the fulfillment of conditions for becoming a member country of the ALADI. The ALADI opens its field of actions for the rest of Latin America through multilateral links or partial agreements with other countries and integration areas of the continent (Article 25). The Latin-American Integration Association also contemplates the horizontal cooperation with other integration movements in the world and partial actions with third developing countries or their respective integration areas (Article 27). ## Institutional structure {#institutional_structure} Council of Ministers of Foreign Affairs The Council of Ministers is the supreme body of the ALADI, and adopts the decisions for the superior political management of the integration process. It is constituted by the Ministers of Foreign Affairs of the member countries. Notwithstanding, when one of such member countries assigns the competence of the integration affairs to a different Minister or Secretary of State, the member countries may be represented, with full powers, by the respective Minister or Secretary. It is convened by the Committee of Representatives, meets and makes decisions with the presence of all the member countries. Evaluation and Convergence Conference It is in charge, among others, of analyzing the functioning of the integration process in all its aspects, promoting the convergence of the partial scope agreements seeking their progressive multilateralization, and promoting greater scope actions as regards economic integration. It is made up of Plenipotentiaries of the member countries. Committee of Representatives It is the permanent political body and negotiating forum of the ALADI, where all the initiatives for the fulfillment of the objectives established by the 1980 Montevideo Treaty are analyzed and agreed on. It is composed of a Permanent Representative of each member country with right to one vote and an Alternate Representative. It meets regularly every 15 days and its Resolutions are adopted by the affirmative vote of two thirds of the member countries. General Secretariat It is the technical body of the ALADI, and it may propose, evaluate, study and manage for the fulfillment of the objectives of the ALADI. It is composed of technical and administrative personnel, and directed by a Secretary-General, who has the support of two Undersecretaries, elected for a three-year period, renewable for the same term. ## Secretaries general {#secretaries_general} - 1980--1984 `{{flagicon\|PAR}}`{=mediawiki} Julio César Schupp (Paraguay) - 1984--1987 `{{flagicon\|URU}}`{=mediawiki} Juan José Real (Uruguay) - 1987--1990 `{{flagicon\|ARG}}`{=mediawiki} Norberto Bertaina (Argentina) - 1990--1993 `{{flagicon\|COL}}`{=mediawiki} Jorge Luis Ordóñez (Colombia) - 1993--1999 `{{flagicon\|BRA}}`{=mediawiki} Antônio José de Cerqueira Antunes (Brasil) - 2000--2005 `{{flagicon\|VEN}}`{=mediawiki} Juan Francisco Rojas Penso (Venezuela) - 2005--2008 `{{flagicon\|URU}}`{=mediawiki} Didier Opertti (Uruguay) - 2008--2009 `{{flagicon\|PAR}}`{=mediawiki} Bernardino Hugo Saguier-Caballero (Paraguay) - 2009--2011 `{{flagicon\|PAR}}`{=mediawiki} José Félix Fernández Estigarribia (Paraguay) - 2011--2017 `{{flagicon\|ARG}}`{=mediawiki} Carlos Álvarez (Argentina) - 2017-- `{{flagicon\|MEX}}`{=mediawiki} Alejandro de la Peña Navarrete (Mexico)	2025-06-20T00:00:00
2,858	Aircraft spotting	Aircraft spotting or planespotting is a hobby consisting of observing and tracking aircraft, which is usually accomplished by photography or videography. Besides monitoring aircraft, planespotters also record information regarding airports, air traffic control communications, airline routes, and more. ## History and evolution {#history_and_evolution} Aviation enthusiasts have been watching airplanes and other aircraft since aviation began. However, as a hobby (distinct from active/wartime work), planespotting did not appear until the second half of the 20th century. During World War II and the subsequent Cold War, some countries encouraged their citizens to become \"planespotters\" in an \"observation corps\" or similar public body for reasons of public security. Britain had the Royal Observer Corps which operated between 1925 and 1995. A journal called The Aeroplane Spotter was published in January 1940. The publication included a glossary that was refined in 2010 and published online. The development of technology and global resources enabled a revolution in planespotting. Point and shoot cameras, DSLRs and walkie talkies have significantly changed the hobby. With the help of the internet, websites such as FlightAware and Flightradar24 have made it possible for planespotters to track and locate specific aircraft around the world. Websites such as airliners.net, Instagram and YouTube allow spotters to upload their photos or videos of their sightings and share them with viewers worldwide. ## Techniques When spotting aircraft, observers generally notice the key attributes of an aircraft, such as a distinctive noise from its engine, the number of contrails it is producing, or its callsign. Observers can also assess the size of the aircraft and the number, type, and position of its engines. Another distinctive attribute is the position of wings relative to the fuselage and the degree to which they are swept rearwards. The wings may be above the fuselage, below it, or fixed at midpoint. The number of wings indicates whether it is a monoplane, biplane or triplane. The position of the tailplane relative to the fin(s) and the shape of the fin are other attributes. The configuration of the landing gear can be distinctive, as well as the size and shape of the cockpit and passenger windows along with the layout of emergency exits and doors. Other features include the speed, cockpit placement, colour scheme or special equipment that changes the silhouette of the aircraft. Taken together these traits will enable the identification of an aircraft. If the observer is familiar with the airfield being used by the aircraft and its normal traffic patterns, they are more likely to leap quickly to a decision about the aircraft\'s identity -- they may have seen the same type of aircraft from the same angle many times. This is particularly prevalent if the aircraft spotter is spotting commercial aircraft, operated by airlines that have a limited fleet. Spotters use equipment such as ADS-B decoders to track the movements of aircraft. The two most famous devices used are the AirNav Systems RadarBox and Kinetic Avionics SBS series. Both of them read and process the radar data and show the movements on a computer screen. Another tool that spotters can use are apps such as FlightRadar24 or Flightaware, where they can look at arrival and departure schedules and track the location of aircraft that have their transponder on. Most of the decoders also allow the exporting of logs from a certain route or airport. ## Spotting styles {#spotting_styles} Some spotters will note and compile the markings, a national insignia or airline livery or logo, a squadron badge or code letters in the case of a military aircraft. Published manuals allow more information to be deduced, such as the delivery date or the manufacturer\'s construction number. Camouflage markings differ, depending on the surroundings in which that aircraft is expected to operate. In general, most spotters attempt to see as many aircraft of a given type, a particular airline, or a particular subset of aircraft such as business jets, commercial airliners, military and/or general aviation aircraft. Some spotters attempt to see every airframe and are known as \"frame spotters.\" Others are keen to see every registration worn by each aircraft. Ancillary activities might include listening-in to air traffic control transmissions (using radio scanners, where that is legal), liaising with other \"spotters\" to clear up uncertainties as to what aircraft have been seen at specific times or in particular places. Several internet mailing list groups have been formed to help communicate aircraft seen at airports, queries and anomalies. These groups can cater to certain regions, certain aircraft types, or may appeal to a wider audience. The result is that information on aircraft movements can be delivered worldwide in a real-time fashion to spotters. The hobbyist might travel long distances to visit different airports, to see an unusual aircraft, or to view the remains of aircraft withdrawn from use. Air shows usually draw large numbers of spotters as they are opportunities to enter airfields and air bases worldwide that are usually closed to the public and to see displayed aircraft at close range. Some aircraft may be placed in the care of museums (see Aviation archaeology) -- or perhaps be cannibalized in order to repair a similar aircraft already preserved. Aircraft registrations can be found in books, with online resources, or in monthly magazines from enthusiast groups. Most spotters maintained books of different aircraft fleets and would underline or check each aircraft seen. Each year, a revised version of the books would be published and the spotter would need to re-underline every aircraft seen. With the development of commercial aircraft databases spotters were finally able to record their sightings in an electronic database and produce reports that emulated the underlined books. Thanks to the Internet and live video streaming, planespotters are now able to watch departure and arrival traffic from anywhere in the world with Internet access. Airline Videos Live, based in Los Angeles at LAX and streaming since 2019, offers several days of streaming weekly on their exclusive YouTube channel in a highly polished format, manned by \"The Plane Jockeys\". In addition to LAX, AVL also streams from airports such as San Francisco (SFO), New York (JFK), Phoenix (PHX) and even Sint Maarten, and have a following more than 830,000 subscribers, dwarfing the smaller streaming channels in the area. ## Legal ramifications {#legal_ramifications} The legal repercussions of the hobby were dramatically shown in November 2001 when fourteen aircraft spotters (twelve British, two Dutch) were arrested by Greek police after being observed at an open day at the Greek Air Force base at Kalamata. They were charged with espionage and faced a possible 20-year prison sentence if found guilty. After being held for six weeks, they were eventually released on \$11,696 (£9,000) bail, and the charges reduced to the misdemeanor charge of illegal information collection. They returned for their trial in April, 2002 and were found guilty, with eight of the group sentenced to three years, the rest for one year. At their appeal a year later, all were acquitted. ## As airport watch groups {#as_airport_watch_groups} In the wake of the targeting of airports by terrorists, enthusiasts\' organisations and police in the UK have cooperated in creating a code of conduct for planespotters, in a similar vein to guidelines devised for train spotters. By asking enthusiasts to contact police if spotters believe they see or hear something suspicious, this is an attempt to allow enthusiasts to continue their hobby while increasing security around airports. Birmingham and Stansted pioneered this approach in Britain and prior to the 2012 London Olympics, RAF Northolt introduced a Flightwatch scheme based on the same cooperative principles. These changes are also being made abroad in countries such as Australia, where aviation enthusiasts are reporting suspicious or malicious actions to police. The organisation of such groups has now been echoed in parts of North America. For example, the Bensenville, Illinois police department have sponsored an Airport Watch group at the Chicago O\'Hare Airport. Members are issued identification cards and given training to accurately record and report unusual activities around the airport perimeter. (Members are not permitted airside.) Meetings are attended and supported by the FBI, Chicago Department of Aviation and the TSA who also provide regular training to group members. The Bensenville program was modeled on similar programs in Toronto, Ottawa and Minneapolis. In 2009, a similar airport watch group was organized between airport security and local aircraft spotters at Montréal--Pierre Elliott Trudeau International Airport. As of 2016, the group has 46 members and a special phone number to use to contact police if suspicious activity is seen around the airport area. ## Extraordinary rendition {#extraordinary_rendition} Following the events of 9/11, information collected by planespotters helped uncover what is known as extraordinary rendition by the CIA. Information on unusual movements of rendition aircraft provided data that was mapped by critical geographers such as Trevor Paglen and the Institute for Applied Autonomy. These data and maps led first to news reports and then to a number of governmental and inter-governmental investigations.	2025-06-20T00:00:00
2,866	Ammeter	An ammeter (abbreviation of ampere meter) is an instrument used to measure the current in a circuit. Electric currents are measured in amperes (A), hence the name. For direct measurement, the ammeter is connected in series with the circuit in which the current is to be measured. An ammeter usually has low resistance so that it does not cause a significant voltage drop in the circuit being measured. Instruments used to measure smaller currents, in the milliampere or microampere range, are designated as milliammeters or microammeters. Early ammeters were laboratory instruments that relied on the Earth\'s magnetic field for operation. By the late 19th century, improved instruments were designed which could be mounted in any position and allowed accurate measurements in electric power systems. It is generally represented by letter \'A\' in a circuit. ## History The relation between electric current, magnetic fields and physical forces was first noted by Hans Christian Ørsted in 1820, who observed a compass needle was deflected from pointing North when a current flowed in an adjacent wire. The tangent galvanometer was used to measure currents using this effect, where the restoring force returning the pointer to the zero position was provided by the Earth\'s magnetic field. This made these instruments usable only when aligned with the Earth\'s field. Sensitivity of the instrument was increased by using additional turns of wire to multiply the effect -- the instruments were called \"multipliers\". The word rheoscope as a detector of electrical currents was coined by Sir Charles Wheatstone about 1840 but is no longer used to describe electrical instruments. The word makeup is similar to that of rheostat (also coined by Wheatstone) which was a device used to adjust the current in a circuit. Rheostat is a historical term for a variable resistance, though unlike rheoscope may still be encountered. ## Types Some instruments are panel meters, meant to be mounted on some sort of control panel. Of these, the flat, horizontal or vertical type is often called an edgewise meter. ### Moving-coil {#moving_coil} The D\'Arsonval galvanometer is a moving coil ammeter. It uses magnetic deflection, where current passing through a coil placed in the magnetic field of a permanent magnet causes the coil to move. The modern form of this instrument was developed by Edward Weston, and uses two spiral springs to provide the restoring force. The uniform air gap between the iron core and the permanent magnet poles make the deflection of the meter linearly proportional to current. These meters have linear scales. Basic meter movements can have full-scale deflection for currents from about 25 microamperes to 10 milliamperes. Because the magnetic field is polarised, the meter needle acts in opposite directions for each direction of current. A DC ammeter is thus sensitive to which polarity it is connected in; most are marked with a positive terminal, but some have centre-zero mechanisms and can display currents in either direction. A moving coil meter indicates the average (mean) of a varying current through it, which is zero for AC. For this reason, moving-coil meters are only usable directly for DC, not AC. This type of meter movement is extremely common for both ammeters and other meters derived from them, such as voltmeters and ohmmeters. ### Moving magnet {#moving_magnet} Moving magnet ammeters operate on essentially the same principle as moving coil, except that the coil is mounted in the meter case, and a permanent magnet moves the needle. Moving magnet Ammeters are able to carry larger currents than moving coil instruments, often several tens of amperes, because the coil can be made of thicker wire and the current does not have to be carried by the hairsprings. Indeed, some Ammeters of this type do not have hairsprings at all, instead using a fixed permanent magnet to provide the restoring force. ### Electrodynamic An electrodynamic ammeter uses an electromagnet instead of the permanent magnet of the d\'Arsonval movement. This instrument can respond to both alternating and direct current and also indicates true RMS for AC. See wattmeter for an alternative use for this instrument. ### Moving-iron {#moving_iron} Moving iron ammeters use a piece of iron which moves when acted upon by the electromagnetic force of a fixed coil of wire. The moving-iron meter was invented by Austrian engineer Friedrich Drexler in 1884. This type of meter responds to both direct and alternating currents (as opposed to the moving-coil ammeter, which works on direct current only). The iron element consists of a moving vane attached to a pointer, and a fixed vane, surrounded by a coil. As alternating or direct current flows through the coil and induces a magnetic field in both vanes, the vanes repel each other and the moving vane deflects against the restoring force provided by fine helical springs. The deflection of a moving iron meter is proportional to the square of the current. Consequently, such meters would normally have a nonlinear scale, but the iron parts are usually modified in shape to make the scale fairly linear over most of its range. Moving iron instruments indicate the RMS value of any AC waveform applied. Moving iron ammeters are commonly used to measure current in industrial frequency AC circuits. ### Hot-wire {#hot_wire} In a hot-wire ammeter, a current passes through a wire which expands as it heats. Although these instruments have slow response time and low accuracy, they were sometimes used in measuring radio-frequency current. These also measure true RMS for an applied AC. ### Digital In much the same way as the analogue ammeter formed the basis for a wide variety of derived meters, including voltmeters, the basic mechanism for a digital meter is a digital voltmeter mechanism, and other types of meter are built around this. Digital ammeter designs use a shunt resistor to produce a calibrated voltage proportional to the current flowing. This voltage is then measured by a digital voltmeter, through use of an analog-to-digital converter (ADC); the digital display is calibrated to display the current through the shunt. Such instruments are often calibrated to indicate the RMS value for a sine wave only, but many designs will indicate true RMS within limitations of the wave crest factor. ### Integrating There is also a range of devices referred to as integrating ammeters. In these ammeters the current is summed over time, giving as a result the product of current and time; which is proportional to the electrical charge transferred with that current. These can be used for metering energy (the charge needs to be multiplied by the voltage to give energy) or for estimating the charge of a battery or capacitor. ## Picoammeter A picoammeter, or pico ammeter, measures very low electric current, usually from the picoampere range at the lower end to the milliampere range at the upper end. Picoammeters are used where the current being measured is below the limits of sensitivity of other devices, such as multimeters. Most picoammeters use a \"virtual short\" technique and have several different measurement ranges that must be switched between to cover multiple decades of measurement. Other modern picoammeters use log compression and a \"current sink\" method that eliminates range switching and associated voltage spikes. Special design and usage considerations must be observed in order to reduce leakage current which may swamp measurements such as special insulators and driven shields. Triaxial cable is often used for probe connections. ## Application Ammeters must be connected in series with the circuit to be measured. For relatively small currents (up to a few amperes), an ammeter may pass the whole of the circuit current. For larger direct currents, a shunt resistor carries most of the circuit current and a small, accurately-known fraction of the current passes through the meter movement. For alternating current circuits, a current transformer may be used to provide a convenient small current to drive an instrument, such as 1 or 5 amperes, while the primary current to be measured is much larger (up to thousands of amperes). The use of a shunt or current transformer also allows convenient location of the indicating meter without the need to run heavy circuit conductors up to the point of observation. In the case of alternating current, the use of a current transformer also isolates the meter from the high voltage of the primary circuit. A shunt provides no such isolation for a direct-current ammeter, but where high voltages are used it may be possible to place the ammeter in the \"return\" side of the circuit which may be at low potential with respect to earth. Ammeters must not be connected directly across a voltage source since their internal resistance is very low and excess current would flow. Ammeters are designed for a low voltage drop across their terminals, much less than one volt; the extra circuit losses produced by the ammeter are called its \"burden\" on the measured circuit(I). Ordinary Weston-type meter movements can measure only milliamperes at most, because the springs and practical coils can carry only limited currents. To measure larger currents, a resistor called a shunt is placed in parallel with the meter. The resistances of shunts is in the integer to fractional milliohm range. Nearly all of the current flows through the shunt, and only a small fraction flows through the meter. This allows the meter to measure large currents. Traditionally, the meter used with a shunt has a full-scale deflection (FSD) of `{{nowrap\|50 mV}}`{=mediawiki}, so shunts are typically designed to produce a voltage drop of `{{nowrap\|50 mV}}`{=mediawiki} when carrying their full rated current. To make a multi-range ammeter, a selector switch can be used to connect one of a number of shunts across the meter. It must be a make-before-break switch to avoid damaging current surges through the meter movement when switching ranges. A better arrangement is the Ayrton shunt or universal shunt, invented by William E. Ayrton, which does not require a make-before-break switch. It also avoids any inaccuracy because of contact resistance. In the figure, assuming for example, a movement with a full-scale voltage of 50 mV and desired current ranges of 10 mA, 100 mA, and 1 A, the resistance values would be: R1 = 4.5 ohms, R2 = 0.45 ohm, R3 = 0.05 ohm. And if the movement resistance is 1000 ohms, for example, R1 must be adjusted to 4.525 ohms. Switched shunts are rarely used for currents above 10 amperes. Zero-center ammeters are used for applications requiring current to be measured with both polarities, common in scientific and industrial equipment. Zero-center ammeters are also commonly placed in series with a battery. In this application, the charging of the battery deflects the needle to one side of the scale (commonly, the right side) and the discharging of the battery deflects the needle to the other side. A special type of zero-center ammeter for testing high currents in cars and trucks has a pivoted bar magnet that moves the pointer, and a fixed bar magnet to keep the pointer centered with no current. The magnetic field around the wire carrying current to be measured deflects the moving magnet. Since the ammeter shunt has a very low resistance, mistakenly wiring the ammeter in parallel with a voltage source will cause a short circuit, at best blowing a fuse, possibly damaging the instrument and wiring, and exposing an observer to injury. In AC circuits, a current transformer can be used to convert the large current in the main circuit into a smaller current more suited to a meter. Some designs of transformer are able to directly convert the magnetic field around a conductor into a small AC current, typically either `{{nowrap\|1 A}}`{=mediawiki} or `{{nowrap\|5 A}}`{=mediawiki} at full rated current, that can be easily read by a meter. In a similar way, accurate AC/DC non-contact ammeters have been constructed using Hall effect magnetic field sensors. A portable hand-held clamp-on ammeter is a common tool for maintenance of industrial and commercial electrical equipment, which is temporarily clipped over a wire to measure current. Some recent types have a parallel pair of magnetically soft probes that are placed on either side of the conductor.	2025-06-20T00:00:00
2,868	Amanda Hesser	Amanda Hesser (born 1971) is an American food writer, editor, cookbook author and entrepreneur. Most notably, she was the food editor of The New York Times Magazine, the editor of T Living, a quarterly publication of The New York Times, author of The Essential New York Times Cookbook which was a New York Times bestseller, and co-founder and CEO of Food52. ## Biography After finishing her first book, in 1997, Hesser was hired as a food reporter for The New York Times where she wrote more than 750 stories. While at the Times, Hesser wrote about the influence of Costco on the wine industry, and how the Farmer Consumer Advisory Committee made decisions for the New York City Greenmarket. She was also among the first to write about Ferran Adrià of El Bulli in a major American publication. Hesser was involved in two cases of conflict of interest while working at the Times. In 2004, she awarded the restaurant Spice Market a three-star rating without disclosing that the year before, the restaurant\'s owner, Jean-Georges Vongerichten, had provided a complimentary jacket blurb for her book Cooking for Mr. Latte. In 2007, Hesser published a favorable review of Vegetable Harvest by Patricia Wells without noting that in 1999, Wells had provided a jacket blurb for Hesser\'s book The Cook and the Gardener. In both cases, the Times subsequently pointed out the conflicts of interest with editors\' notes. While Hesser left the Times in March 2008 to focus on the development of Food52, she continued to write the \"Recipe Redux\" feature for the Times magazine until February 27, 2011. As co-founder and CEO of Food52, she has raised two rounds of investment from parties including Lerer Hippeau Ventures and Bertelsmann Digital Media Investments. Food52 has won numerous notable awards, including the James Beard Foundation Award for Publication of the Year (2012) and the International Association of Culinary Professionals Award for Best Website (2013). In February 2017, noting that 92 percent of the company was white, she and her co-founder Merrill Stubbs \"issued a statement about the ways in which the company intended to redress a lack of racial equality in its workplace.\" By the following January, \"they published a follow-up letter updating readers on the progress of their efforts, stating that their staff had been reduced to being 76 percent white.\" Hesser was featured in Food & Wine\'s 40 under 40 list, was named one of the 50 most influential women in food by Gourmet magazine, and had a cameo as herself in the film Julie & Julia. Hesser lives in Brooklyn Heights with her husband, Tad Friend, a staff writer for The New Yorker, and their two children.	2025-06-20T00:00:00
2,877	Augustine of Canterbury	Augustine of Canterbury (early 6th century -- most likely 26 May 604) was a Christian monk who became the first archbishop of Canterbury in the year 597. He is considered the \"Apostle to the English\". Augustine was the prior of a monastery in Rome when Pope Gregory the Great chose him in 595 to lead a mission, usually known as the Gregorian mission, to Britain to Christianize King Æthelberht and his Kingdom of Kent from Anglo-Saxon paganism. Kent was likely chosen because Æthelberht commanded major influence over neighbouring Anglo-Saxon kingdoms in addition to his marriage to Bertha, a Frankish princess, who was expected to exert some influence over her husband. Before reaching Kent, the missionaries had considered turning back, but Gregory urged them on, and in 597, Augustine landed on the Isle of Thanet and proceeded to Æthelberht\'s main town of Canterbury. King Æthelberht converted to Christianity and allowed the missionaries to preach freely, giving them land to found a monastery outside the city walls. Augustine was consecrated as a bishop and converted many of the king\'s subjects, including thousands during a mass baptism on Christmas Day in 597. Pope Gregory sent more missionaries in 601, along with encouraging letters and gifts for the churches, although attempts to persuade the native British bishops to submit to Augustine\'s authority failed. Roman bishops were established at London, and Rochester in 604, and a school was founded to train Anglo-Saxon priests and missionaries. Augustine also arranged the consecration of his successor, Laurence of Canterbury. The archbishop probably died in 604 and was soon revered as a saint. ## Background to the mission {#background_to_the_mission} After the withdrawal of the Roman legions from their province of Britannia in 410, the inhabitants were left to defend themselves against the attacks of the Saxons. Before the Roman withdrawal, Britannia had been converted to Christianity and produced the ascetic Pelagius. Britain sent three bishops to the Council of Arles in 314, and a Gaulish bishop went to the island in 396 to help settle disciplinary matters. Material remains testify to a growing presence of Christians, at least until around 360. After the Roman legions departed, pagan tribes settled the southern parts of the island while western Britain, beyond the Anglo-Saxon kingdoms, remained Christian. This native British Church developed in isolation from Rome under the influence of missionaries from Ireland and was centred on monasteries instead of bishoprics. Other distinguishing characteristics were its calculation of the date of Easter and the style of the tonsure haircut that clerics wore. Evidence for the survival of Christianity in the eastern part of Britain during this time includes the survival of the cult of Saint Alban and the occurrence in place names of eccles, derived from the Latin ecclesia, meaning \"church\". There is no evidence that these native Christians tried to convert the Anglo-Saxons. The invasions destroyed most remnants of Roman civilisation in the areas held by the Saxons and related tribes, including the economic and religious structures. It was against this background that Pope Gregory I decided to send a mission, often called the Gregorian mission, to convert the Anglo-Saxons to Christianity in 595. The Kingdom of Kent was ruled by Æthelberht, who had married a Christian princess named Bertha before 588, and perhaps earlier than 560. Bertha was the daughter of Charibert I, one of the Merovingian kings of the Franks. As one of the conditions of her marriage, she brought a bishop named Liudhard with her to Kent. Together in Canterbury, they restored a church that dated to Roman times`{{snd}}`{=mediawiki}possibly the current St Martin\'s Church. Æthelberht was a pagan at this point but allowed his wife freedom of worship. One biographer of Bertha states that under his wife\'s influence, Æthelberht asked Pope Gregory to send missionaries. The historian Ian N. Wood feels that the initiative came from the Kentish court as well as the queen. Other historians, however, believe that Gregory initiated the mission, although the exact reasons remain unclear. Bede, an 8th-century monk who wrote a history of the English church, recorded a famous story in which Gregory saw fair-haired Saxon slaves from Britain in the Roman slave market and was inspired to try to convert their people. More practical matters, such as the acquisition of new provinces acknowledging the primacy of the papacy, and a desire to influence the emerging power of the Kentish kingdom under Æthelberht, were probably involved. The mission may have been an outgrowth of the missionary efforts against the Lombards who, as pagans and Arian Christians, were not on good relations with the Catholic church in Rome. Aside from Æthelberht\'s granting of freedom of worship to his wife, the choice of Kent was probably dictated by a number of other factors. Kent was the dominant power in southeastern Britain. Since the eclipse of King Ceawlin of Wessex in 592, Æthelberht was the bretwalda, or leading Anglo-Saxon ruler; Bede refers to Æthelberht as having imperium (overlordship) south of the River Humber. Trade between the Franks and Æthelberht\'s kingdom was well established, and the language barrier between the two regions was apparently only a minor obstacle, as the interpreters for the mission came from the Franks. Lastly, Kent\'s proximity to the Franks allowed support from a Christian area. There is some evidence, including Gregory\'s letters to Frankish kings in support of the mission, that some of the Franks felt that they had a claim to overlordship over some of the southern British kingdoms at this time. The presence of a Frankish bishop could also have lent credence to claims of overlordship, if Bertha\'s Bishop Liudhard was felt to be acting as a representative of the Frankish church and not merely as a spiritual advisor to the queen. Frankish influence was not merely political; archaeological remains attest to a cultural influence as well. In 595, Gregory chose Augustine, who was the prior of the Abbey of St Andrew in Rome, to head the mission to Kent. The pope selected monks to accompany Augustine and sought support from the Frankish royalty and clergy in a series of letters, of which some copies survive in Rome. He wrote to King Theuderic II of Burgundy and to King Theudebert II of Austrasia, as well as their grandmother Brunhild, seeking aid for the mission. Gregory thanked King Chlothar II of Neustria for aiding Augustine. Besides hospitality, the Frankish bishops and kings provided interpreters and Frankish priests to accompany the mission. By soliciting help from the Frankish kings and bishops, Gregory helped to assure a friendly reception for Augustine in Kent, as Æthelbert was unlikely to mistreat a mission which visibly had the support of his wife\'s relatives and people. Moreover, the Franks appreciated the chance to participate in mission that would extend their influence in Kent. Chlothar, in particular, needed a friendly realm across the Channel to help guard his kingdom\'s flanks against his fellow Frankish kings. Sources make no mention of why Pope Gregory chose a monk to head the mission. Pope Gregory once wrote to Æthelberht complimenting Augustine\'s knowledge of the Bible, so Augustine was evidently well educated. Other qualifications included administrative ability, for Gregory was the abbot of St Andrews as well as being pope, which left the day-to-day running of the abbey to Augustine, the prior. ## Arrival and first efforts {#arrival_and_first_efforts} Augustine was accompanied by Laurence of Canterbury, his eventual successor to the archbishopric, and a group of about 40 companions, some of whom were monks. Soon after leaving Rome, the missionaries halted, daunted by the nature of the task before them. They sent Augustine back to Rome to request papal permission to return. Gregory refused and sent Augustine back with letters encouraging the missionaries to persevere. In 597, Augustine and his companions landed in Kent. They achieved some initial success soon after their arrival: Æthelberht permitted the missionaries to settle and preach in his capital of Canterbury where they used the church of St Martin\'s for services. Neither Bede nor Gregory mentions the date of Æthelberht\'s conversion, but it probably took place in 597. In the early medieval period, large-scale conversions required the ruler\'s conversion first, and Augustine is recorded as making large numbers of converts within a year of his arrival in Kent. Also, by 601, Gregory was writing to both Æthelberht and Bertha, calling the king his son and referring to his baptism. A late medieval tradition, recorded by the 15th-century chronicler Thomas Elmham, gives the date of the king\'s conversion as Whit Sunday, or 2 June 597; there is no reason to doubt this date, although there is no other evidence for it. Against a date in 597 is a letter of Gregory\'s to Patriarch Eulogius of Alexandria in June 598, which mentions the number of converts made by Augustine, but does not mention any baptism of the king. However, it is clear that by 601 the king had been converted. His baptism likely took place at Canterbury. Augustine established his episcopal see at Canterbury. It is not clear when and where Augustine was consecrated as a bishop. Bede, writing about a century later, states that Augustine was consecrated by the Frankish Archbishop Ætherius of Arles, Gaul (France) after the conversion of Æthelberht. Contemporary letters from Pope Gregory, however, refer to Augustine as a bishop before he arrived in England. A letter of Gregory\'s from September 597 calls Augustine a bishop, and one dated ten months later says Augustine had been consecrated on Gregory\'s command by bishops of the German lands. The historian R. A. Markus discusses the various theories of when and where Augustine was consecrated, and suggests he was consecrated before arriving in England, but argues the evidence does not permit deciding exactly where this took place. Soon after his arrival, Augustine founded the monastery of Saints Peter and Paul, which later became St Augustine\'s Abbey, on land donated by the king. In a letter Gregory wrote to the patriarch of Alexandria in 598, he claimed that more than 10,000 Christians had been baptised; the number may be exaggerated but there is no reason to doubt that a mass conversion took place. However, there were probably some Christians already in Kent before Augustine arrived, remnants of the Christians who lived in Britain in the later Roman Empire. Little literary traces remain of them, however. One other effect of the king\'s conversion by Augustine\'s mission was that the Frankish influence on the southern kingdoms of Britain was decreased. After these conversions, Augustine sent Laurence back to Rome with a report of his success, along with questions about the mission. Bede records the letter and Gregory\'s replies in chapter 27 of his Historia ecclesiastica gentis Anglorum; this section of the History is usually known as the Libellus responsionum. Augustine asked for Gregory\'s advice on a number of issues, including how to organise the church, the punishment for church robbers, guidance on who was allowed to marry whom, and the consecration of bishops. Other topics were relations between the churches of Britain and Gaul, childbirth and baptism, and when it was lawful for people to receive communion and for a priest to celebrate mass. Further missionaries were sent from Rome in 601. They brought a pallium for Augustine and a present of sacred vessels, vestments, relics, and books. The pallium was the symbol of metropolitan status, and signified that Augustine was now an archbishop unambiguously associated with the Holy See. Along with the pallium, a letter from Gregory directed the new archbishop to consecrate 12 suffragan bishops as soon as possible and to send a bishop to York. Gregory\'s plan was that there would be two metropolitans, one at York and one at London, with 12 suffragan bishops under each archbishop. As part of this plan, Augustine was expected to transfer his archiepiscopal see to London from Canterbury. This move never happened; no contemporary sources give the reason, but it was probably because London was not part of Æthelberht\'s domains. Instead, London was part of the kingdom of Essex, ruled by Æthelberht\'s nephew Saebert of Essex, who converted to Christianity in 604. The historian S. Brechter has suggested that the metropolitan see was indeed moved to London, and that it was only with the abandonment of London as a see after the death of Æthelberht that Canterbury became the archiepiscopal see. This theory contradicts Bede\'s version of events, however. ## Additional work {#additional_work} In 604, Augustine founded two more bishoprics in Britain. Two men who had come to Britain with him in 601 were consecrated, Mellitus as Bishop of London and Justus as Bishop of Rochester. Bede relates that Augustine, with the help of the king, \"recovered\" a church built by Roman Christians in Canterbury. It is not clear if Bede meant that Augustine rebuilt the church or that Augustine merely reconsecrated a building that had been used for pagan worship. Archaeological evidence seems to support the latter interpretation; in 1973 the remains of an aisled building dating from the Romano-British period were uncovered just south of the present Canterbury Cathedral. The historian Ian Wood argues that the existence of the Libellus points to more contact between Augustine and the native Christians because the topics covered in the work are not restricted to conversion from paganism, but also dealt with relations between differing styles of Christianity. Augustine failed to extend his authority to the Christians in Wales and Dumnonia to the west. Gregory had decreed that these Christians should submit to Augustine and that their bishops should obey him, apparently believing that more of the Roman governmental and ecclesiastical organisation survived in Britain than was actually the case. According to the narrative of Bede, the Britons in these regions viewed Augustine with uncertainty, and their suspicion was compounded by a diplomatic misjudgement on Augustine\'s part. In 603, Augustine and Æthelberht summoned the British bishops to a meeting south of the Severn. These guests retired early to confer with their people, who, according to Bede, advised them to judge Augustine based upon the respect he displayed at their next meeting. When Augustine failed to rise from his seat on the entrance of the British bishops, they refused to recognise him as their archbishop. There were, however, deep differences between Augustine and the British church that perhaps played a more significant role in preventing an agreement. At issue were the tonsure, the observance of Easter, and practical and deep-rooted differences in approach to asceticism, missionary endeavours, and how the church itself was organised. Some historians believe that Augustine had no real understanding of the history and traditions of the British church, damaging his relations with their bishops. Also, there were political dimensions involved, as Augustine\'s efforts were sponsored by the Kentish king, and at this period the Wessex and Mercian kingdoms were expanding to the west, into areas held by the Britons. ## Further success {#further_success} Gregory also instructed Augustine on other matters. Temples were to be consecrated for Christian use, and feasts, if possible, moved to days celebrating Christian martyrs. One religious site was revealed to be a shrine of a local St Sixtus, whose worshippers were unaware of details of the martyr\'s life or death. They may have been native Christians, but Augustine did not treat them as such. When Gregory was informed, he told Augustine to stop the cult and use the shrine for the Roman St Sixtus. Gregory legislated on the behaviour of the laity and the clergy. He placed the new mission directly under papal authority and made it clear that English bishops would have no authority over Frankish counterparts nor vice versa. Other directives dealt with the training of native clergy and the missionaries\' conduct. The King\'s School, Canterbury claims Augustine as its founder, which would make it the world\'s oldest existing school, but the first documentary records of the school date from the 16th century. Augustine did establish a school, and soon after his death Canterbury was able to send teachers out to support the East Anglian mission. Augustine received liturgical books from the pope, but their exact contents are unknown. They may have been some of the new mass books that were being written at this time. The exact liturgy that Augustine introduced to England remains unknown, but it would have been a form of the Latin language liturgy in use at Rome. ## Death and legacy {#death_and_legacy} Before his death, Augustine consecrated Laurence of Canterbury as his successor to the archbishopric, probably to ensure an orderly transfer of office. Although at the time of Augustine\'s death, 26 May 604, the mission barely extended beyond Kent, his undertaking introduced a more active missionary style into the British Isles. Despite the earlier presence of Christians in Ireland and Wales, no efforts had been made to try to convert the Saxon invaders. Augustine was sent to convert the descendants of those invaders, and eventually became the decisive influence in Christianity in most of the British Isles. Much of his success came about because of Augustine\'s close relationship with Æthelberht, which gave the archbishop time to establish himself. Augustine\'s example also influenced the great missionary efforts of the Anglo-Saxon Church. Augustine\'s body was originally buried in the portico of what is now St Augustine\'s, Canterbury, but it was later exhumed and placed in a tomb within the abbey church, which became a place of pilgrimage and veneration. After the Norman Conquest the cult of St Augustine was actively promoted. After the Conquest, his shrine in St Augustine\'s Abbey held a central position in one of the axial chapels, flanked by the shrines of his successors Laurence and Mellitus. King Henry I of England granted St. Augustine\'s Abbey a six-day fair around the date on which Augustine\'s relics were translated to his new shrine, from 8 September through 13 September. A life of Augustine was written by Goscelin around 1090, but this life portrays Augustine in a different light, compared to Bede\'s account. Goscelin\'s account has little new historical content, mainly being filled with miracles and imagined speeches. Building on this account, later medieval writers continued to add new miracles and stories to Augustine\'s life, often quite fanciful. These authors included William of Malmesbury, who claimed that Augustine founded Cerne Abbey, the author (generally believed to be John Brompton) of a late medieval chronicle containing invented letters from Augustine, and a number of medieval writers who included Augustine in their romances. Another problem with investigating Augustine\'s saintly cult is the confusion resulting because most medieval liturgical documents mentioning Augustine do not distinguish between Augustine of Canterbury and Augustine of Hippo, a fourth-century saint. Medieval Scandinavian liturgies feature Augustine of Canterbury quite often, however. During the English Reformation, Augustine\'s shrine was destroyed and his relics were lost. Augustine\'s shrine was re-established in March 2012 at the church of St. Augustine in Ramsgate, Kent, very close to the mission\'s landing site. St Augustine\'s Cross, a Celtic cross erected in 1884, marks the spot in Ebbsfleet, Thanet, East Kent, where the newly arrived Augustine is said to have first met and preached to the awaiting King Ethelbert.	2025-06-20T00:00:00
2,883	Active Server Pages	{{ multiple issues\\| `{{primary sources\|date=February 2015}}`{=mediawiki} `{{more citations needed\|date=February 2015}}`{=mediawiki} }} `{{Infobox software \| name = Active Server Pages (ASP) \| logo = \| developer = [[Microsoft]] \| latest_release_version = 3.0 \| latest_release_date = {{Start date and age\|2000\|2\|17}} \| genre = [[Web application framework]] \| license = [[Proprietary software]] \| website = }}`{=mediawiki} `{{Infobox file format \| name = Active Server Pages \| logo = \| extension = .asp \| mime = \| type code = \| uniform type = \| magic = \| owner = [[Microsoft]] \| genre = \| container for = \| contained by = \| extended from = \| extended to = \| standard = \| free = \| url = }}`{=mediawiki} Active Server Pages (ASP) is Microsoft\'s first server-side scripting language and engine for dynamic web pages. It was first released in December 1996, before being superseded in January 2002 by ASP.NET. ## History Initially released as an add-on to Internet Information Services (IIS) via the Windows NT 4.0 Option Pack (1996), it is included as a component of Windows Server (since the initial release of Windows 2000 Server). There have been three versions of ASP, each introduced with different versions of IIS: - ASP 1.0 was released in December 1996 as part of IIS 3.0 - ASP 2.0 was released in September 1997 as part of IIS 4.0 - ASP 3.0 was released in November 2000 as part of IIS 5.0 ASP 2.0 provides six built-in objects: Application, ASPError, Request, Response, Server, and Session. A `Session` object, for example, represents a session that maintains the state of variables from page to page. The Active Scripting engine\'s support of the Component Object Model enables ASP websites to access functionality in compiled libraries such as dynamic-link libraries. ASP 3.0 does not differ greatly from ASP 2.0 but it does offer some additional enhancements such as Server.Transfer method, Server.Execute method, and an enhanced ASPError object. ASP 3.0 also enables buffering by default and optimized the engine for better performance. ASP was supported until 14 January 2020 on Windows 7. The use of ASP pages will be supported on Windows 8 for a minimum of 10 years from the Windows 8 release date. ASP is supported in all available versions of IIS as of 2024. ## Architecture ASP uses scripting on the server to generate content that is sent to the client\'s web browser via HTTP response. The ASP interpreter reads and executes all script code between \<% and %\> tags, the result of which is content generation. These scripts were written using VBScript, JScript, or PerlScript. The `@Language` directive, the `{{tag\|script\|s\|params=language="''language''" runat="server"}}`{=mediawiki} syntax or server configuration can be used to select the language. In the example below, Response.Write Now() is in an HTML page; it would be dynamically replaced by the current time of the server. +----------------------------+----------------------------+ \| Server side \| Client Side \| +============================+============================+ \| ``` aspx-vb \| ``` output \| \| The server's current time: \| The server's current time: \| \| <% \| 8/11/2015 6:24:45 PM \| \| Response.Write Now() \| ``` \| \| %> \| \| \| ``` \| \| +----------------------------+----------------------------+ Web pages with the .asp filename extension use ASP, although some web sites disguise their choice of scripting language for security purposes by using the more common .htm or .html extensions. Pages with the .aspx extension use compiled ASP.NET; however, ASP.NET pages may still include some ASP scripting. The introduction of ASP.NET led to use of the term Classic ASP for the original technology. Sun Java System ASP (formerly ChiliSoft ASP) was a popular and reportedly complete emulator, but it has been discontinued. ### The Server object {#the_server_object} The server object allows connections to databases (ADO), filesystem, and use of components installed on the server. ``` vbscript <% Dim oAdoCon, oAdoRec, oAdoStm, oCdoCon, oCdoMsg, oSciDic, oSciFsm, oMswAdr Set oAdoCon = Server.CreateObject("ADODB.Connection") Set oAdoRec = Server.CreateObject("ADODB.Recordset") Set oAdoStm = Server.CreateObject("ADODB.Stream") Set oCdoCon = Server.CreateObject("CDO.Configuration") Set oCdoMsg = Server.CreateObject("CDO.Message") Set oSciDic = Server.CreateObject("Scripting.Dictionary") Set oSciFsm = Server.CreateObject("Scripting.FileSystemObject") Set oMswAdr = Server.CreateObject("MSWC.Swingbridge") %> ``` ### The Application object {#the_application_object} This object stores global variables, which are variables accessible to all users. ``` aspx-vb <% Application("Ali") = "My ASP Application" Response.Write "Welcome to " & Server.HTMLEncode(Application("Ali")) & "!" %> ``` ### The Session object {#the_session_object} Stores variables accessible only to a single visitor, which are local variables. ``` vbscript <% If Len(Request.QueryString("name")) > 0 Then Session("name") = Request.QueryString("name") End If Response.Write "Welcome " & Server.HTMLEncode(Session("name")) & "!" %> ``` The session object is file based and multiple concurrent read and/or write requests will be blocked and processed in turn. ### The Err object {#the_err_object} Allows the management and fixing of non-fatal errors. ``` vbscript <% On Error Resume Next Response.Write 1 / 0 ' Division by zero If Err.Number <> 0 Then Response.Write "Error Code: " & Server.HTMLEncode(Err.Number) & "<br />" Response.Write "Error Source: " & Server.HTMLEncode(Err.Source) & "<br />" Response.Write "Error Description: " & Server.HTMLEncode(Err.Description) & "<br />" Err.Clear End If %> ```	2025-06-20T00:00:00
2,889	Amorphous solid	In condensed matter physics and materials science, an amorphous solid (or non-crystalline solid) is a solid that lacks the long-range order that is a characteristic of a crystal. The terms \"glass\" and \"glassy solid\" are sometimes used synonymously with amorphous solid; however, these terms refer specifically to amorphous materials that undergo a glass transition. Examples of amorphous solids include glasses, metallic glasses, and certain types of plastics and polymers. ## Etymology The term \"Amorphous\" comes from the Greek a (\"without\"), and morphé (\"shape, form\"). ## Structure Amorphous materials have an internal structure of molecular-scale structural blocks that can be similar to the basic structural units in the crystalline phase of the same compound. Unlike in crystalline materials, however, no long-range regularity exists: amorphous materials cannot be described by the repetition of a finite unit cell. Statistical measures, such as the atomic density function and radial distribution function, are more useful in describing the structure of amorphous solids. Although amorphous materials lack long range order, they exhibit localized order on small length scales. By convention, short range order extends only to the nearest neighbor shell, typically only 1-2 atomic spacings. Medium range order may extend beyond the short range order by 1-2 nm. ## Fundamental properties of amorphous solids {#fundamental_properties_of_amorphous_solids} ### Glass transition at high temperatures {#glass_transition_at_high_temperatures} The freezing from liquid state to amorphous solid - glass transition - is considered one of the very important and unsolved problems of physics. ### Universal low-temperature properties of amorphous solids {#universal_low_temperature_properties_of_amorphous_solids} At very low temperatures (below 1-10 K), a large family of amorphous solids have various similar low-temperature properties. Although there are various theoretical models, neither glass transition nor low-temperature properties of glassy solids are well understood on the fundamental physics level. Amorphous solids is an important area of condensed matter physics aiming to understand these substances at high temperatures of glass transition and at low temperatures towards absolute zero. From the 1970s, low-temperature properties of amorphous solids were studied experimentally in great detail. For all of these substances, specific heat has a (nearly) linear dependence as a function of temperature, and thermal conductivity has nearly quadratic temperature dependence. These properties are conventionally called anomalous being very different from properties of crystalline solids. On the phenomenological level, many of these properties were described by a collection of tunnelling two-level systems. Nevertheless, the microscopic theory of these properties is still missing after more than 50 years of the research. Remarkably, a dimensionless quantity of internal friction is nearly universal in these materials. This quantity is a dimensionless ratio (up to a numerical constant) of the phonon wavelength to the phonon mean free path. Since the theory of tunnelling two-level states (TLSs) does not address the origin of the density of TLSs, this theory cannot explain the universality of internal friction, which in turn is proportional to the density of scattering TLSs. The theoretical significance of this important and unsolved problem was highlighted by Anthony Leggett. ## Nano-structured materials {#nano_structured_materials} Amorphous materials will have some degree of short-range order at the atomic-length scale due to the nature of intermolecular chemical bonding. Furthermore, in very small crystals, short-range order encompasses a large fraction of the atoms; nevertheless, relaxation at the surface, along with interfacial effects, distorts the atomic positions and decreases structural order. Even the most advanced structural characterization techniques, such as X-ray diffraction and transmission electron microscopy, can have difficulty distinguishing amorphous and crystalline structures at short-size scales. ## Characterization of amorphous solids {#characterization_of_amorphous_solids} Due to the lack of long-range order, standard crystallographic techniques are often inadequate in determining the structure of amorphous solids. A variety of electron, X-ray, and computation-based techniques have been used to characterize amorphous materials. Multi-modal analysis is very common for amorphous materials. ### X-ray and neutron diffraction {#x_ray_and_neutron_diffraction} Unlike crystalline materials, which exhibit strong Bragg diffraction, the diffraction patterns of amorphous materials are characterized by broad and diffuse peaks. As a result, detailed analysis and complementary techniques are required to extract real space structural information from the diffraction patterns of amorphous materials. It is useful to obtain diffraction data from both X-ray and neutron sources as they have different scattering properties and provide complementary data. Pair distribution function analysis can be performed on diffraction data to determine the probability of finding a pair of atoms separated by a certain distance. Another type of analysis that is done with diffraction data of amorphous materials is radial distribution function analysis, which measures the number of atoms found at varying radial distances away from an arbitrary reference atom. From these techniques, the local order of an amorphous material can be elucidated. ### X-ray absorption fine-structure spectroscopy {#x_ray_absorption_fine_structure_spectroscopy} X-ray absorption fine-structure spectroscopy is an atomic scale probe making it useful for studying materials lacking in long-range order. Spectra obtained using this method provide information on the oxidation state, coordination number, and species surrounding the atom in question as well as the distances at which they are found. ### Atomic electron tomography {#atomic_electron_tomography} The atomic electron tomography technique is performed in transmission electron microscopes capable of reaching sub-Angstrom resolution. A collection of 2D images taken at numerous different tilt angles is acquired from the sample in question and then used to reconstruct a 3D image. After image acquisition, a significant amount of processing must be done to correct for issues such as drift, noise, and scan distortion. High-quality analysis and processing using atomic electron tomography results in a 3D reconstruction of an amorphous material detailing the atomic positions of the different species that are present. ### Fluctuation electron microscopy {#fluctuation_electron_microscopy} Fluctuation electron microscopy is another transmission electron microscopy-based technique that is sensitive to the medium-range order of amorphous materials. Structural fluctuations arising from different forms of medium-range order can be detected with this method. Fluctuation electron microscopy experiments can be done in conventional or scanning transmission electron microscope mode. ### Computational techniques {#computational_techniques} Simulation and modeling techniques are often combined with experimental methods to characterize structures of amorphous materials. Commonly used computational techniques include density functional theory, molecular dynamics, and reverse Monte Carlo. ## Uses and observations {#uses_and_observations} ### Amorphous thin films {#amorphous_thin_films} Amorphous phases are important constituents of thin films. Thin films are solid layers of a few nanometres to tens of micrometres thickness that are deposited onto a substrate. So-called structure zone models were developed to describe the microstructure of thin films as a function of the homologous temperature (T~h~), which is the ratio of deposition temperature to melting temperature. According to these models, a necessary condition for the occurrence of amorphous phases is that (T~h~) has to be smaller than 0.3. The deposition temperature must be below 30% of the melting temperature. ### Superconductivity Regarding their applications, amorphous metallic layers played an important role in the discovery of superconductivity in amorphous metals made by Buckel and Hilsch. The superconductivity of amorphous metals, including amorphous metallic thin films, is now understood to be due to phonon-mediated Cooper pairing. The role of structural disorder can be rationalized based on the strong-coupling Eliashberg theory of superconductivity. ### Thermal protection {#thermal_protection} Amorphous solids typically exhibit higher localization of heat carriers compared to crystalline, giving rise to low thermal conductivity. Products for thermal protection, such as thermal barrier coatings and insulation, rely on materials with ultralow thermal conductivity. ### Technological uses {#technological_uses} Today, optical coatings made from TiO~2~, SiO~2~, Ta~2~O~5~ etc. (and combinations of these) in most cases consist of amorphous phases of these compounds. Much research is carried out into thin amorphous films as a gas-separating membrane layer. The technologically most important thin amorphous film is probably represented by a few nm thin SiO~2~ layers serving as isolator above the conducting channel of a metal-oxide semiconductor field-effect transistor (MOSFET). Also, hydrogenated amorphous silicon (Si:H) is of technical significance for thin-film solar cells. ### Pharmaceutical use {#pharmaceutical_use} In the pharmaceutical industry, some amorphous drugs have been shown to offer higher bioavailability than their crystalline counterparts as a result of the higher solubility of the amorphous phase. However, certain compounds can undergo precipitation in their amorphous form in vivo and can then decrease mutual bioavailability if administered together. Studies of GDC-0810 ASDs show a strong interrelationship between microstructure, physical properties and dissolution performance. ### In soils {#in_soils} Amorphous materials in soil strongly influence bulk density, aggregate stability, plasticity, and water holding capacity of soils. The low bulk density and high void ratios are mostly due to glass shards and other porous minerals not becoming compacted. Andisol soils contain the highest amounts of amorphous materials. ## Phase Amorphous phases were a phenomenon of particular interest for the study of thin-film growth. The growth of polycrystalline films is often used and preceded by an initial amorphous layer, the thickness of which may amount to only a few nm. The most investigated example is represented by the unoriented molecules of thin polycrystalline silicon films. Wedge-shaped polycrystals were identified by transmission electron microscopy to grow out of the amorphous phase only after the latter has exceeded a certain thickness, the precise value of which depends on deposition temperature, background pressure, and various other process parameters. The phenomenon has been interpreted in the framework of Ostwald\'s rule of stages that predicts the formation of phases to proceed with increasing condensation time towards increasing stability.	2025-06-20T00:00:00
2,899	ArgoUML	ArgoUML is an UML diagramming application written in Java and released under the open source Eclipse Public License. By virtue of being a Java application, it is available on any platform supported by Java SE. ## History ArgoUML was originally developed at UC Irvine by Jason E. Robbins, leading to his Ph.D. It was an open source project hosted by Tigris.org and moved in 2019 to GitHub. The ArgoUML project included more than 19,000 registered users and over 150 developers. In 2003, ArgoUML won the Software Development Magazine\'s annual Readers\' Choice Award in the "Design and Analysis Tools" category. ArgoUML development has suffered from lack of manpower. For example, Undo has been a perpetually requested feature since 2003 but has not been implemented yet. ## Features According to the official feature list, ArgoUML is capable of the following: - All 9 UML 1.4 diagrams are supported. - Closely follows the UML standard. - Platform independent -- Java 1.5+ and C++. - Click and Go! with Java Web Start (no setup required, starts from your web browser). - Standard UML 1.4 Metamodel. - XMI support. - Export diagrams as GIF, PNG, PS, EPS, PGML and SVG. - Available in ten languages: EN, EN-GB, DE, ES, IT, RU, FR, NB, PT, ZH. - Advanced diagram editing and zoom. - Built-in design critics provide unobtrusive review of design and suggestions for improvements. - Extensible modules interface. - OCL support. - Forward engineering (code generation supports C++ and C#, Java, PHP 4, PHP 5, Ruby and, with less mature modules, Ada, Delphi and SQL). - Reverse engineering / JAR/class file import. ## Weaknesses - ArgoUML does not yet completely implement the UML standard. - Partial undo feature (working for graphics edits ) - Java Web Start launching may no longer work reliably. See Java Web Start.	2025-06-20T00:00:00
2,900	File archiver	In computing, a file archiver is utility software that combines files into a single archive file `{{endash}}`{=mediawiki} or in less common cases, multiple files. A minimally designed archiver might concatenate the content of files along with file name and length. A more advanced archiver stores additional metadata, such as the timestamps, file attributes and access control information. An archiver might compress input file content to reduce the size of the resulting archive. The process of making an archive file is called archiving or packing. Reconstructing the original files from an archive is called unarchiving, unpacking or extracting. ## Multics In the early days of computing, Multics provided the `{{code\|archive}}`{=mediawiki} command `{{endash}}`{=mediawiki} a basic archiver without compression `{{endash}}`{=mediawiki} that descended from the CTSS command of the same name. Multics also provided a magnetic tape archiver command, `{{code\|ta}}`{=mediawiki}, which was perhaps the forerunner of the Unix command `{{code\|tar}}`{=mediawiki}. ## Unix As the Unix archive tools ar, tar, and cpio do not provide compression, other tools, such as gzip, bzip2, or xz, are used to compress an archive file after it is created and to decompress before extracting. Not only does separating archiving from compressing follow the Unix philosophy that each tool should provide a single capability; not attempt to accomplish everything with one tool, it has the following advantages: - As compression technology progresses, users may use a different compression tool without having to change how they use the archiver. - Solid compression allows the compressor to take advantage of redundancy across the multiple archived files in order to achieve better compression than simply compressing each file individually. Disadvantages include: - Extracting a single file requires decompressing the entire file, which can be costly in terms of time and storage space; adding a file to an existing archive requires both decompression and recompression. - The archive becomes damage-prone; corruption in any part of the file might cause all files to be lost. A challenge: - Compression cannot take advantage of redundancy between files unless the compression window is larger than the size of an individual file; for example, gzip uses DEFLATE, which typically operates with a 32768-byte window, whereas bzip2 uses a Burrows--Wheeler transform roughly 27 times bigger; xz defaults to 8 MiB but supports significantly larger windows. Generally, extensions are successively added to the file name to indicate the operations performed and therefore required to read a file. For example, archiving with `{{code\|tar}}`{=mediawiki} command and then compressing with `{{code\|gzip}}`{=mediawiki} command might be indicated with the `.tar.gz` extension. ## Windows Archiving tools on Windows tend to have a graphical user interface (GUI) and to include compression `{{endash}}`{=mediawiki} including the built-in Windows feature as well as commonly used, third-party tools such as WinRAR and 7-Zip. Unlike the built-in feature, WinRAR and 7-zip also provide a command-line interface (CLI) and solid compression.	2025-06-20T00:00:00
2,907	Axayacatl	Axayacatl (`{{IPAc-en\|ˌ\|æ\|ʃ\|ə\|ˈ\|j\|ɑː\|k\|ə\|t\|əl}}`{=mediawiki}; āxāyacatl `{{IPA\|nah\|aːʃaːˈjákatɬ\|\|Axayakatl.ogg}}`{=mediawiki}; Axayácatl `{{IPA\|es\|axaˈʝakatɬ\|}}`{=mediawiki}; meaning \"face of water\"; c. 1449--1481) was the sixth \[\[tlatoani\]\] of the \[\[altepetl\]\] of Tenochtitlan and Emperor of the Aztec Triple Alliance. ## Biography ### Early life and background {#early_life_and_background} Axayacatl was a son of the princess Atotoztli II and her cousin, prince Tezozomoc. He was a grandson of the Emperors Moctezuma I and Itzcoatl. He was a descendant of the king Cuauhtototzin. He was a successor of Moctezuma and his brothers were Emperors Tizoc and Ahuitzotl and his sister was the Queen Chalchiuhnenetzin. He was an uncle of the Emperor Cuauhtémoc and father of Emperors Moctezuma II and Cuitláhuac. ### Rise to power {#rise_to_power} During his youth, his military prowess gained him the favor influential figures such as Nezahualcoyotl and Tlacaelel I, and thus, upon the death of Moctezuma I in 1469, he was chosen to ascend to the throne, much to the displeasure of his two older brothers, Tizoc and Ahuitzotl. It is also important that the Great Sun Stone, also known as the Aztec Calendar, was carved under his leadership. An earthquake in Tenochtitlán occurred and destroyed many homes. ### Military actions and death {#military_actions_and_death} Using as a pretext the insulting behavior of a few Tlatelolcan citizens, Axayacatl invaded his neighbor, killed its ruler, Moquihuix, and replaced him with a military governor. The Tlatelolcans lost any voice they had in forming Aztec policy. Axayacatl largely dedicated his twelve-year reign to consolidating his militaristic repute: he led successful campaigns against the neighboring altepetl of Tlatelolco in 1473 (see Battle of Tlatelolco) and the Matlatzinca of the Toluca Valley in 1474, but was finally defeated by the Tarascans of Michoacán in 1476. Despite some subsequent minor triumphs, Axayacatl\'s defeat at the hands of the Tarascans irreversibly marred his image, as it constituted the only major defeat suffered by the Aztecs up to that moment. In spite of his young age, he fell gravely ill in 1480, passing away a mere year later, in 1481, whereupon he was succeeded by his brother Tizoc. ### Axayacatl the poet {#axayacatl_the_poet} Axayacatl wrote two poems. The first, Ycuic Axayayatzin (English: \"Song of Axayacatl\") is a defense against his brothers and critics; the second, Huehue cuicatl (English: \"Song of the Ancients\") is a lament written after his defeat in Michoacan. ## In popular culture {#in_popular_culture} - The Obsidian and Blood series by Aliette de Bodard are set in the last year of the reign of Axayacatl and the first years of the reign of Tizoc, with their youngest brother Ahuitzotl appearing as a primary character.	2025-06-20T00:00:00
2,908	Ahuitzotl	Ahuitzotl (āhuitzotl\]\], `{{IPA\|nah\|aːˈwit͡sot͡ɬ\|-\|Awisotl.ogg}}`{=mediawiki}) was the eighth Aztec ruler, the Huey Tlatoani of the city of Tenochtitlan, son of princess Atotoztli II. His name literally means \"Water Thorny\" and was also applied to the otter. It is also theorized that more likely, the animal called ahuitzotl is actually the water opossum, the hand symbolizing its prehensile tail, which otters notably lack. Either Ahuitzotl or his predecessor Tizoc was the first tlatoani of Tenochtitlan to assume the title Huey Tlatoani (\"supreme tlatoani\") to make their superiority over the other cities in the Triple Alliance (Aztec Empire) clear. Ahuitzotl was responsible for much of the expansion of the Mexica domain, and consolidated the empire\'s power after emulating his predecessor. He took power as Emperor in the year 7 Rabbit (1486), after the death of his predecessor and brother, Tizoc. He had two sons, the kings Chimalpilli II and Cuauhtémoc, and one daughter. ## Biography Perhaps the greatest known military leader of pre-Columbian Mesoamerica, Ahuizotl began his reign by suppressing a Huastec rebellion, and then swiftly more than doubled the size of lands under Aztec dominance. He conquered the Mixtec, Zapotec, and other peoples from Pacific Coast of Mexico down to the western part of Guatemala. Ahuizotl also supervised a major rebuilding of Tenochtitlan on a grander scale including the expansion of the Great Pyramid or Templo Mayor in the year 8 Reed (1487). He presided over the introduction of the great-tailed grackle into the Valley of Mexico, the earliest documented case of human-mediated bird introduction in the Western Hemisphere. Ahuizotl died in the year 10 Rabbit (1502) and was succeeded by his nephew, Moctezuma II. Ahuizotl took his name from the animal ahuizotl, which the Aztecs considered to be a legendary creature in its own right rather than a mere mythical representation of the king. In January 2021 the INAH proposed moving the statues of Ahuizotl and Itzcóatl, known as the Indios Verdes, from the Parque del Mestizaje in Gustavo A. Madero, Mexico City to the Paseo de la Reforma. "The transfer means a reading of the urban space, recovering the historical discourse that gave rise to the formation of a set of monuments and roundabouts on Paseo de la Reforma, conceived at the end of the 19th century, with the idea of honoring the Reformation, a great transformation that it meant for Mexico, but to recover a historical reading that began precisely by underlining the Mexican splendor and the importance of the pre-Hispanic or Mesoamerican antecedents of our country", Diego Prieto, director of INAH said. ## In popular culture {#in_popular_culture} Under the name Teomitl, Ahuitzotl is a primary character in the Obsidian and Blood series by Aliette de Bodard, which are set in the last year of the reign of Axayacatl and the first years of the reign of Tizoc. In the historical fiction novel Aztec by Gary Jennings, Ahuitzotl is a prominent character. Set in the time just before the arrival of the Spanish Conquistadors, it accounts his construction of the many expansions of Tenochtitlan, and wars of conquest, trade, and proclivities.	2025-06-20T00:00:00
2,916	Belgian hip-hop	Belgian hip hop music has a few rappers stemming from Africa and Italy. Belgium, like France, controlled African countries like the Democratic Republic of the Congo (formerly Zaire), Rwanda, and Burundi until the early 1960s. Like in France, immigrants from these countries started to study and live in Belgium. The Belgian hip hop scene started in the late 1980s with a U.S.-based techno/hip hop group called Technotronic. In the group was an emcee named Ya Kid K from the Democratic Republic of the Congo who later led the group into international fame with hits like \"Pump up the Jam\" and \"Shake That Body\". In 1990, she also joined the group Hi-Tek 3 who were heard on Teenage Mutant Ninja Turtles: The Original Motion Picture Soundtrack. However, the first major pop rapper from Belgium was Benny B, who had a very mainstream and commercial sound. According to the European Music Office\'s report on Music in Europe, this was the first of many pop acts that helped inspire a backlash and the creation of an underground hip hop scene. Also in the late 1980s in the Walloon south of the country, French speaking/rapping Starflam was the biggest name in hip hop. In the Flemish north Dutch speaking/rapping groups like \'t Hof van Commerce, Krapoel In Axe, St Andries MC\'s, and ABN were popular, rapping in their regional dialects. Today, the Belgian hip hop scene is growing. Rappers like Coely, Roméo Elvis and Damso are achieving commercial success in their country and abroad. Other contemporary rappers/formations are Stikstof, Woodie Smalls, L\'Or Du Commun and Isha (rapper).	2025-06-20T00:00:00
2,917	Dutch hip-hop	Dutch hip hop or Nederhop (\"Netherhop\") is hip hop / rap music created by Dutch speaking musicians in the Netherlands and Flanders (Belgium). Although the first Dutch rappers in Europe typically wrote in the English language, this began to change when Osdorp Posse gained a big following of fans. They were the first to record and release hip hop in the Dutch language, perform for big crowds and to achieve chart success with their albums. In 1995, the same year Osdorp Posse had a top 20 chart hit with their album Afslag Osdorp, rapper Extince was the first Dutch rap artist to achieve a top 10 hit in the singles charts with Spraakwater. After rapper Def Rhymz was the first to reach the Dutch main chart with number 1 hits such as Doekoe (Sranan Tongo for \'money\'; 1999), and Schudden (\"Shake (it)\"/\"Shaking\"; 2001) with a more pop, R&B and dance influenced sound, Dutch language hip hop has grown into a staple of mainstream pop music in the Netherlands and Flanders in the 21st century. In 2021, Netherlands music streaming charts were dominated by Dutch rap music artists like Boef, Josylvio, Broederliefde, Lil\' Kleine, Snelle, and Sevn Alias.`{{Update inline \|date=April 2024}}`{=mediawiki} ## History ### 1980s Between 1980 and 1985 a few Dutch Hip Hop records had already been released, but in 1986 Dutch rap duo MC Miker G & DJ Sven had a top 10 hit in at least ten countries across Europe with their Holiday Rap, which sampled Madonna\'s \"Holiday\". It caused notable financial disputes, four years ahead of Vanilla Ice\'s similar sampling troubles with Ice Ice Baby. That same year Dutch rapper Extince released his first record Rap Around The Clock, and in 1987 he scored a modest hit with The Milkshake Rap. However, in the late 1980s Nederhop (\"Netherhop\") emerged, as artists began to rap in Dutch, such as Def Rhymz, Blonnie B, Alex and the CityCrew, Dynamic Rockers, and the Osdorp Posse. Though there is disagreement about who were the first, the pioneers\' work was at first only experimental, except for the Osdorp Posse, a group from Osdorp, a \"hood\" in Amsterdam, who were first to release tracks in Dutch, for instance the single Moordenaar (\"Murderer\") in 1989, marking a beginning milestone of Nederhop. After their frontman, rapper Def P, began by literally translating English raps into Dutch, he started writing original work that still contained peculiar idioms that resulted from his earlier literal rewordings. The result was described by rapper Ali B as highly visual and captivating. Once Extince switched to Dutch in 1994, having rapped in English since 1984, both he and Osdorp Posse became highly influential in Nederhop in the 1990s and beyond. Notable in the late 1980s were All Star Fresh of King Bee topping charts with: \"Back by Dope Demand\" in early 1990 and Rudeboy of Urban Dance Squad who, at the time, were arguably more widely known in New York City than in the Netherlands. DJ and Producer All Star Fresh turned professional as early as 1979. After winning the Dutch Mixing Championships (DMC) in 1988, he was invited for the World Mix Championships in the London Royal Hall and won third place among strong competition. He was invited by Dave Funkenklein to enter the lion\'s den in New York. He made history in the Big Apple of hiphop by being the first non-American to fly into the finals of the World Supremacy Battle of DJs. He gained the highly respected second place of this prestigious DJ contest. The impression that he made that year, resulted in many invitations to perform with artists like Public Enemy, Stetsasonic, Ice T and Ultra Magnetic MCs. All Star Fresh. As performer and producer he is better known as KING BEE. With his second floor filler Back By Dope Demand he achieved one of his biggest hiphop hits. In the Netherlands it resulted in a Top 3 position, and best Dance Product by The Edison Awards in the Netherlands. (The Edison Awards is an award by the Dutch Music Industry.) This also meant that with this title, he was the first black artist to win this award in the Netherlands. After that he appeared as supporting act for Madonnas show in the Netherlands. All Star Fresh kept entering the dance floors. The last titles mentioned were also popular worldwide, selling over 2.4 million copies. He didn\'t only work within projects like King Bee or Capella, but also was featuring well known production teams like Snap (I Got the Power). This teamwork resulted in the single Lets Get Busy (Clubland Quarts feat Snap `{{sic\|introductin}}`{=mediawiki} King Bee). This record ended up No. 1 in the Billboard Dance Charts (United States). Other productions in this line were Deepzone \"It\'s Gonna Be All right\", Kellee- my love, Ty Holden- you\'re my Inspiration and His Royal Freshness- They don\'t understand. ### 1990s {#s_1} Urban Dance Squad was a Dutch rap rock band formed after a jam session at a festival in Utrecht in 1986, including rapper/vocalist Rudeboy Remington and DJ DNA (DoNotAsk). The band\'s music is described as a blend of genres, including hard rock, funk, soul, hip hop, reggae, jazz and ska and is compared with Living Colour, Red Hot Chili Peppers and Fishbone. They are still known for their hit single Deeper Shade of Soul, which charted at number 21 in the United States on Billboard Hot 100. In 1989 Osdorp Posse formed, the first rap act solely in the Dutch language. They started out translating N.W.A songs to Dutch, but soon began writing their own rhymes. Dutch rap was still frowned up in general. Many hip hop listeners found it silly to hear raps in a different language than English and the radio and television didn\'t want to have anything to do with it at all. Osdorp Posse overcame this, and gained a small crowd of followers. Indie label Djax Records from Eindhoven picked up on this and signed Osdorp Posse to their label. In 1992 they released their debut album Osdorp Stijl, making it the first ever Dutch language hip hop album. Their beats, created by producer Seda on Amiga 500 with Protracker, had a heavy sound and was similar to U.S. old-school hip hop, while also embracing an own style by making use of samples from metal music. The lyrics were often focussed on social criticism, with frontman Def P describing it as hardcore rap. In Deventer they found their first following, and the first Dutch language hip hop scene was born. The first hip hop groups after Osdorp Posse were Zuid-Oost Posse and Maasstraat Mannen. Dutch rap kept on reaching a bigger crowd, though it still could be considered as an underground genre. A year after the debut album of Osdorp Posse, they released 2 more albums, Roffer Dan Ooit and Vlijmscherp. Paving the way like this, many Dutch rap acts popped up. In 1994 a breakthrough took place with the release of compilation record De Posse: Nederhop Groeit (meaning \"Nederhop is growing\"), presenting no less than 7 different new Dutch rap acts on one record. These groups performed all across the Netherlands, gaining even a bigger audience. By 1996, Djax Records released material by Ouderkerk Kaffers, White Wolf, West Klan, Dr. Doom, Spookrijders, Zuid Oost Posse, Klaas Vaak, Cut, Mach, Vuurwerk, Loco-Motief, Lijkenpikkers, Bitchez & Cream, Space Marines, Jesse, Neuk! and De Uitverkorenen. The media still largely boycotted Dutch rap, while often expressing criticism on the harsh lyrics and lo-fi beats. Despite this, Osdorp Posse managed to build a large following of fans by 1995, resulting in nation-wide sold-out tours and big spots at Dutch festivals. They performed at the Lowlands Festival in 1995, with their popularity getting completely underestimated by the bookers, causing fans to even climb up lightning rigs and poles of the festival tent to be able to experience the set. In 1997 Osdorp Posse did two shows at the biggest festival of The Netherlands, the Pinkpop Festival. On the main day of the festival they performed at the main stage for a packed field of fans, resulting in the biggest Dutch rap show of the decade. By that year the band had 2 albums which charted in the Dutch album charts, while still on an indie label and with virtually no airplay on radio and TV. In 1995 Afslag Osdorp, their fourth album, was the first Dutch language rap album to enter the Album Top 100, for a total of 14 weeks and even a ranking in the top 20. A unique achievement, with a peak position in the charts that would only be matched 7 years later by Brainpower. By then, the band and Dutch rap in general got taken more seriously as well. After the undeniable success live on stage and in the album charts by Osdorp Posse, the lyrical content was getting cautious praise. By the mid-90\'s Def P collaborated with renowned and highly esteemed writers like Remco Campert and was often invited to recite his lyrics at poetry rap festivals like the Double Talk Festival at Paradiso. At the same time a shift took place, when rapper Extince took rap in the Dutch language to a new commercial level and a different audience in 1995. While Osdorp Posse already had big chart successes with their albums, Extince\'s Spraakwater became the first single to make the mainstream pop single charts in the country. The song even made the top 10 of the singles charts and got airplay at the radio. From then on there were two styles dominating the Dutch hip hop landscape. On one side the hardcore rap performers like Osdorp Posse, De Uitverkorenen, Casto and West Klan, who focussed on the content of their lyrics with social criticism, political subjects and knowledge, on often energetic and rough beats. With on the other side Extince, who was more of a storyteller with a slick flow and a knack for wordplay and metaphoric imagery, on funky and laidback beats. A mix of these two styles gave birth to the Spookrijders, a three-man hip-hop group founded in 1996. With MCs Stefan and Clyde rapping about their personal lives and life in Amsterdam as a black man, the Spookrijders even gained respect from non-hip-hop musicians and fans. Most people admired the work of producer/DJ Cliff \'the Jazz\' Nille after releasing Spookrijders debut album De Echte Shit (\"The Real Shit\"). In 1999, Spookrijders hit the charts twice with the hits \"Klokkenluiders\" and \"Ik ben de man.\" Both these songs appeared on the second album, Klokkenluiders van Amsterdam. After some personal arguments among the three crewmembers, Spookrijders split up in 2003, after releasing a third and final album Hey\... Spookies!! In 1999 The Postmen released their rap/reggae mix De Bom (\"The Bom\"), a top three hit-single. They were active across Europe from 1998 to 2003. ### 2000s {#s_2} From 2000 onward, Dutch language hiphop grew considerably, both in number of artists, as well as in popularity, both underground and mainstream. In the early 2000s the MC fronted band Relax got much airplay, mainly impressing with their albums. Since 2002, they released four albums, the first three of which made the Dutch album top 40. Def Rhymz, Spookrijders & Brainpower helped develop the art. Def Rhymz & Brainpower dropped multiple hit records. Described by Ali B. as \"..a white library boy with glasses..\", Brainpower made Dutch rapping accessible to a much greater demographic. With six Top 100 albums, Brainpower is one of the most commercially successful Dutch MC\'s to date. By 2000, about 15 years after their founding, Osdorp Posse still did sold-out tours and still had big album chart success. They even scored a surprise hit song, when Origineel Amsterdams hit the top 10 of the single charts. By then, Dutch rap fully took over from Dutch artists rapping in English, and Osdorp Posse set up their own label to release Dutch rap artists. The same year they released their seventh album Kernramp as the first double album in Dutch rap, with the second disc containing up and coming Dutch rap artists. In the months following its release alone, 17,000 physical copies were sold, unique for Dutch language rap at the time. Having let a permanent mark on their fanbase, when the album was re-released on vinyl in 2019, it became the best-selling album on vinyl the week of release. From the late 1990s, a flourishing underground scene in provincial town Zwolle included rappers Blaxtar, Jawat!, and Kubus, and centered around the group Opgezwolle. Formed in 1998 by rappers Sticky Steez and Phreaco Rico, together with DJ Delic, the band Opgezwolle (punning their town\'s name into \"Swollen\"), was a group making raw hiphop. They released three successful albums, in 2001, 2003, and 2006. Eigen Wereld (\"Own World\"), from 2006, achieved the highest notation of any Dutch-language rap album until then in the Dutch Album Top 100, reaching top 4. In the same year, rapper Typhoon, also from Zwolle, and inspired by aforementioned peer Blaxtar, released his philosophical debut album Tussen Licht en Lucht (\"Between Light and Air\"). The successes of the Zwolle rappers crop boosted other Dutch artists\' confidence and inspired them to be proud of their origins -- whether local, foreign, or mixed. Rapper Typhoon pointed out, that band names of trailblazers like \'Osdorp Posse\' and \'Opgezwolle\' refer to their origins (Amsterdam Osdorp and Zwolle) for an important reason, and tied this to the shift from rapping in English to Dutch, making it more relatable and resonant with the audience. Instead of hard and angry, some 2000s releases stood out fragile and sensitive, for instance the single Je moest waarschijnlijk gaan (\"I Guess You Had to Go\"; 2001) by Brainpower, mourned the loss of his best friend; and the raps of Typhoon are called some of the most poetic. Opgezwolle split up in 2007, but members Rico & Sticks formed a new group: Fakkelbrigade, with Typhoon, Mick 2dope Murray, MC James and beatmaker A.R.T. In 2009, they released the critically acclaimed album Colucci Era. From 2003 through 2006, Lange Frans & Baas B had four top-three hits in the Dutch Top 40, beside three more listings. Zinloos, a sad commentary on senseless violence (\"Zinloos Geweld\"), and their patriotic yet introspective Het Land van .. (\"The Land of..\") gave the duo two number-1 hits, in 2004 and 2005 respectively. In the mid-2000s Cilvaringz, Ali B. Jerome XL and Raymzter were also commercially successful. Ali B featured on other artists\' tracks, most significantly with Marco Borsato on the song \"Wat zou je doen?\" for the charity War Child. He first achieved solo success with \"Ik ben je zat\", featuring Brace, in 2003. Together with music artist Akon, and Ali\'s cousin Yes-R, Ali B made an internationally successful remix of Akon\'s track Ghetto, including additional Dutch lyrics. Yes-R had six Dutch Top 40 hits from 2006 to 2012, including his debut single. Ali B. has sofar had fourteen Top 40 hit singles since 2003, including several top three listings. Jerome XL made a leap to the states in 2006 while recording with many international crews and their members like Jurassic 5, Dilated Peoples, Juice Crew and many others. This was a first for Dutch Hip Hop. In 2005, De Jeugd van Tegenwoordig (\"Kids These Days\") were successful with Watskeburt?! (\"Wuzhappenin?!\"). Rapper Jawat won the \"Grote Prijs van Nederland\" 2006. Another Dutch hip-hop duo are Pete Philly and Perquisite who are already well known in the Netherlands, Germany, and in Japan. A famous Dutch rapper outside the Netherlands is Salah Edin. His album Nederlands Grootste Nachtmerrie (Biggest Nightmare of the Netherlands) won Best Album Award in 2007 and was fully produced by Dr. Dre\'s right-hand man Focus\... He also shot three of the most expensive music videos in the history of Dutch Hip Hop, and through a management deal with Cilvaringz, performed in 34 countries worldwide. ### 2010s {#s_3} Social acceptance of rap / hip hop in the Netherlands was perhaps epitomized, when artist Typhoon performed for the Dutch royal family twice -- both in 2013 and in 2016. In 2015, a self-titled \"New Wave\" generation of \'social media\' (em)powered artists broke through with their eponymous New Wave album, as a temporary collaboration, including Bokoesam, D-Double, Jonna Fraser, Lil\' Kleine, Ronnie Flex, and SFB. Since 2014, rapper group Broederliefde released no less than seven albums, with the \"worst one\" topping at 13 in the charts --- their debut album reached number 3, and their last five albums were consecutive top-2s, with three of them topping the chart. Their third album, Hard Work Pays Off (II) (2016), broke an all-time record by staying at number 1 for 14 weeks, beating a 2003 12-week record, held by Dutch A-list singer Frans Bauer. Nine of their singles also charted in the singles Top 40. In 2016, album WOP! by Lil\' Kleine was the first hip-hop album to reach number 1 on the Album Top 100. In the same year, Ali B\'s third album, Een klein beetje geluk (\"A Little Bit of Happiness\"), proved his best yet, reaching number 7. Starting 2016, rapper Sevn Alias released five consecutive top-10 albums, with his second reaching nr. 1, and the last three consistently reaching top-2 positions. He is highly productive, and is also enjoying extensive success with singles, collaborations, and other track releases. ### 2020s {#s_4} ### Conflicts The Dutch hip-hop scene also saw many conflicts between rappers, followed by diss tracks. The following were among the biggest Dutch feuds in hip-hop: Osdorp Posse vs. Extince, BrainPower vs. Extince, T.H.C vs. Negativ, Kempi vs. Nino, Yukkie B vs. Negativ, T.H.C. vs. Lexxxus, Baas B vs. Kimo, Kempi vs. Mini, Kempi vs. Bloedserieus, Heist Rockah vs. Negativ, and Regga vs. Lexxxus. The feud between T.H.C. and Lexxxus resulted in a fistfight on a hip-hop event, when T.H.C. frontman Rocks got into an argument with Lexxxus and then started the fistfight. ## Genres in Dutch hip hop {#genres_in_dutch_hip_hop} ### Gangsta Dutch gangsta hip hop is currently a large scene together with underground hip-hop. Among the most notable acts and performers are THC, Heinek\'n, Keizer, Kempi, Steen, Hef, Crooks, Adonis and Negativ. The rhythms are influenced by the American rap scene, and the lyrics are often about crime, drugs, money, women and other criminal things. Often coming from Dutch ghettos, lyrics often include themes occurring in these areas. Dutch gangsta hip hop mostly comes from the five largest cities: Amsterdam, Rotterdam, The Hague, Utrecht and Eindhoven. ### Commercial success {#commercial_success} The commercial success of Dutch hip hop is largely made by Brainpower, Yes-R, Ali B, Lange Frans & Baas B and Extince. For a large part of the Dutch hip hop community Yes-R, Ali B and Lange Frans & Baas B are sometimes considered fake because they do a lot of work for children TV stations. Brainpower and Extince however both enjoy a great respect for bringing up hip hop in their native Dutch. Other commercial rappers are De Jeugd van Tegenwoordig, and one of the more popular artists in the Netherlands, Partysquad or The Partysquad. They are a 2-man group, having had success with hits such as \"Stuk\" (Broken), and \"Dat is Die Shit\" (That\'s the shit), with other popular songs in the background such as \"Non Stop\" ft. Brainpower, \"We Gaan Los\" (we\'re going crazy {because of highness or drunkenness}) with Kempi, and \"Wat Wil Je Doen\" (What do you want to do?). ### Dutch oldskool {#dutch_oldskool} The Dutch oldskool exists out of three primary artists, LTH, Osdorp Posse, Extince, Sugacane and Duvelduvel. Osdorp Posse make to what they themselves call hardcore rap and use beats that have much in common with N.W.A. Their lyrics are about racism, prostitution, police and other social subjects. Extince uses very different, more funky kind of beats than Osdorp Posse and uses a completely different rapstyle. Duvelduvel is known as a conceptual hip hop group. ## Notable artists {#notable_artists} Notable Dutch hip hop artists, listed by locality include: `{{columns-list\| * [[Alphen aan den Rijn]]: [[Brainpower]], [[Salah Edin]] * [[Alkmaar]]: [[Boef]], [[The Opposites]] * [[Almere]]: [[Ali B]], [[Josylvio]], [[Raymzter]], [[Jerome XL]] * [[Amsterdam]]: [[Sevn Alias]], [[Brainpower]], [[Osdorp Posse]], [[De Jeugd van Tegenwoordig]], [[The Opposites]], [[D-Men]], [[Lange Frans & Baas B]], [[Appa (rapper)\|Appa]], [[Yes-R]], [[Tuindorp Hustler Click]] (THC), [[Lil' Kleine]] * [[Capelle aan den IJssel]]: [[Ronnie Flex]] * [[Deventer]]: [[Snelle]] * [[Eindhoven]]: [[Fresku]], [[Kempi]] * [[Groningen (city)\|Groningen]]: [[Kraantje Pappie]] * [[Nijmegen]]: [[Gers Pardoel]] * [[Oosterhout]]: [[Extince]] * [[Rotterdam]]: [[E-Life]], [[U-Niq]], [[Winne (rapper)\|Winne]], [[Feis (rapper)\|Feis]], [[Hef (rapper)\|Hef]], [[Postmen (band)\|Postmen]] * [[The Hague]]: [[Frenna]] * [[Utrecht]]: [[Kyteman]] * [[Tilburg]]: [[Cilvaringz]] * [[Zoetermeer]]: [[Mr. Probz]] * [[Zwolle]]: [[Opgezwolle]], [[Typhoon (rapper)\|Typhoon]] }}`{=mediawiki}	2025-06-20T00:00:00
2,926	Antarctic	The Antarctic (`{{IPAc-en\|æ\|n\|ˈ\|t\|ɑr\|(\|k\|)\|t\|ɪ\|k}}`{=mediawiki}, `{{IPAc-en\|USalso\|æ\|n\|t\|ˈ\|ɑr\|(\|k\|)\|t\|ɪ\|k}}`{=mediawiki}; commonly `{{IPAc-en\|æ\|n\|ˈ\|ɑr\|t\|ɪ\|k}}`{=mediawiki})`{{refn\|The word was originally pronounced without the first {{IPA\|/k/}} sound, but the [[spelling pronunciation]] has become common and is often considered more correct. The pronunciation without the first /k/ and the first /t/ is however widespread and a typical phenomenon of English in many other similar words too.<ref>{{cite web \|url=https://ahdictionary.com/word/search.html?q=Antarctica \|archive-url=https://web.archive.org/web/20151208004718/https://www.ahdictionary.com/word/search.html?q=Antarctica\|url-status=dead \|title=The American Heritage Dictionary entry: Antarctica \|publisher=[[HarperCollins]] \|archive-date=2015-12-08 \|website=ahdictionary.com}}</ref> The ''c'' was added to the spelling for etymological reasons and then began to be pronounced, but (as with other spelling pronunciations) at first only by less educated people.<ref>{{cite book \|last=Crystal\|first=David \|date=2006 \|title=The Fight for English \|publisher=Oxford University Press \|isbn=978-0-19-920764-0 \|page=[https://archive.org/details/fightforenglishh00crys/page/172 172] \|url-access=registration \|url=https://archive.org/details/fightforenglishh00crys/page/172}}</ref><ref>{{cite web \|last=Harper \|first=Douglas \|title=Antarctic \|work=Online Etymology Dictionary \|url=http://www.etymonline.com/index.php?term=antarctic&allowed_in_frame=0 \|access-date=16 November 2011 \|url-status=live \|archive-url=https://web.archive.org/web/20120111152745/http://www.etymonline.com/index.php?term=antarctic&allowed_in_frame=0 \|archive-date=11 January 2012}}</ref>\|group="Note"}}`{=mediawiki} is the polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is diametrically opposite of the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau, and other island territories located on the Antarctic Plate or south of the Antarctic Convergence. The Antarctic region includes the ice shelves, waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence, a zone approximately 32 to wide and varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere, of which 5.5 percent (14 million km^2^) is the surface area of the Antarctica continent itself. All of the land and ice shelves south of 60°S latitude are administered under the Antarctic Treaty System. Biogeographically, the Antarctic realm is one of eight biogeographic realms on Earth\'s land surface. Climate change in Antarctica is particularly important because the melting of the Antarctic ice sheet has a high potential to add to the global sea level rise. Further, this melting also disrupts the flow of Southern Ocean overturning circulation, which would have significant effects on the local climate and marine ecosystem functioning. There is no permanent country in Antarctica. ## Geography As defined by the Antarctic Treaty System, the Antarctic region is everything south of the 60°S latitude. The Treaty area covers Antarctica and the archipelagos of the Balleny Islands, Peter I Island, Scott Island, the South Orkney Islands, and the South Shetland Islands. However, this area does not include the Antarctic Convergence, a transition zone where the cold waters of the Southern Ocean collide with the warmer waters of the north, forming a natural border to the region. Because the Convergence changes seasonally, the Convention for the Conservation of Antarctic Marine Living Resources approximates the Convergence line by joining specified points along parallels of latitude and meridians of longitude. The implementation of the convention is managed through an international commission headquartered in Hobart, Australia, by an efficient system of annual fishing quotas, licenses, and international inspectors on the fishing vessels, as well as satellite surveillance. The islands situated between 60°S latitude parallel to the south and the Antarctic Convergence to the north and their respective 200 nmi exclusive economic zones fall under the national jurisdiction of the countries that possess them: South Georgia and the South Sandwich Islands (United Kingdom), Bouvet Island (Norway), and Heard and McDonald Islands (Australia). Kerguelen Islands (France; also an EU Overseas territory) are situated in the Antarctic Convergence area, while the Isla Grande de Tierra del Fuego, Falkland Islands, Isla de los Estados, Hornos Island with Cape Horn, Diego Ramírez Islands, Campbell Island, Macquarie Island, Amsterdam and Saint Paul Islands, Crozet Islands, Prince Edward Islands, Gough Island, and Tristan da Cunha group remain north of the Convergence and thus outside the Antarctic region. ## Ecology ### Antarctica A variety of animals live in Antarctica for at least some of the year, including: - Seals - Penguins - South Georgia pipits - Albatrosses - Antarctic petrels - Whales - Fish, such as Antarctic icefish, Antarctic toothfish - Squid, including the colossal squid - Antarctic krill Most of the Antarctica continent is permanently covered by ice and snow, leaving less than 1 percent of the land exposed. There are only two species of flowering plant, Antarctic hair grass and Antarctic pearlwort, but a range of mosses, liverworts, lichens and macrofungi. ### Sub-Antarctic Islands {#sub_antarctic_islands} Biodiversity among terrestrial flora and fauna is low on the islands: studies have theorized that the harsh climate was a major contributor towards species richness, but multiple correlations have been found with area, temperature, remoteness of islands, and food chain stability. For example, herbivorous insects are poor in number due to low plant richness, and likewise, indigenous bird numbers are related to insects, which are a major food source. - Isla de los Estados (Argentina) - Isla Grande de Tierra del Fuego (Chile) ## Conservation The Antarctic hosts the world\'s largest protected area comprising 1.07 million km^2^, the South Georgia and the South Sandwich Islands Marine Protection Area created in 2012. The latter exceeds the surface area of another vast protected territory, the Greenland National Park\'s 972,000 km2. (While the Ross Sea Marine Protection Area established in 2016 is still larger at 1.55 million km^2^, its protection is set to expire in 35 years.) To protect the area, all Antarctic ships over 500 tonnes are subject to mandatory regulations under the Polar Code, adopted by the International Maritime Organization (in force since 1 January 2017). ## Climate change {#climate_change} thumb\\|upright=1.25\\|left\\|Since the 1970s, the upper cell of the Southern Ocean overturning circulation has strengthened, while the lower cell weakened. These changes have been linked to the melting of the Antarctic ice sheet. `{{excerpt\|Climate change in Antarctica\|paragraphs=3,4\|files=no}}`{=mediawiki} ## Society ### People The first recorded sighting of Antarctica is credited to the Spaniard Gabriel de Castilla, who reported seeing distant southern snow-capped mountains in 1603. The first Antarctic land discovered was the island of South Georgia, visited by the English merchant Anthony de la Roché in 1675. Although such myths and speculation about a Terra Australis (\"Southern Land\") date back to antiquity, the first confirmed sighting of the continent of Antarctica is commonly accepted to have occurred in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny. The Australian James Kerguelen Robinson (1859--1914) was the first human born in the Antarctic, on board the sealing ship Offley in the Gulf of Morbihan (Royal Sound then), Kerguelen Island on 11 March 1859. The first human born and raised on an Antarctic island was Solveig Gunbjørg Jacobsen born on 8 October 1913 in Grytviken, South Georgia. Emilio Marcos Palma (born 7 January 1978) is an Argentine man who was the first documented person born on the continent of Antarctica at the Esperanza Base. His father, Captain Jorge Palma, was head of the Argentine Army detachment at the base. While ten people have been born in Antarctica since, Palma\'s birthplace remains the southernmost. In late 1977, Silvia Morella de Palma, who was then seven months pregnant, was airlifted to Esperanza Base, in order to complete her pregnancy in the base. The airlift was a part of the Argentine solutions to the sovereignty dispute over territory in Antarctica. Emilio was automatically granted Argentine citizenship by the government since his parents were both Argentine citizens, and he was born in the claimed Argentine Antarctica. Palma can be considered to be the first native Antarctican. The Antarctic region had no indigenous population when first discovered, and its present inhabitants comprise a few thousand transient scientific and other personnel working on tours of duty at the several dozen research stations maintained by various countries. However, the region is visited by more than 40,000 tourists annually, the most popular destinations being the Antarctic Peninsula area (especially the South Shetland Islands) and South Georgia Island. In December 2009, the growth of tourism, with consequences for both the ecology and the safety of the travellers in its great and remote wilderness, was noted at a conference in New Zealand by experts from signatories to the Antarctic Treaty. The definitive results of the conference were presented at the Antarctic Treaty states\' meeting in Uruguay in May 2010. ### Time zones {#time_zones} Because Antarctica surrounds the South Pole, it is theoretically located in all time zones. For practical purposes, time zones are usually based on territorial claims or the time zone of a station\'s owner country or supply base. ## List of offshore islands {#list_of_offshore_islands} ### North of 60°S latitude {#north_of_60s_latitude} `{{Columns-list\|colwidth=30em\| * {{Flag\|Bouvet Island}} ([[Norway]]) * {{Flag\|Heard Island and McDonald Islands}} ([[Australia]]) [[Heard Island and McDonald Islands#Geography\|Heard Island]] [[McDonald Islands (Australia)\|McDonald Islands]] * {{Flagdeco\|French Southern Territories}} [[Kerguelen Islands]] ([[France]]) * {{Flag\|South Georgia and the South Sandwich Islands}} ([[The Crown\|United Kingdom]]) [[South Georgia and the South Sandwich Islands#South Georgia group\|South Georgia Islands]] * [[Shag Rocks (South Georgia)\|Shag Rocks]] * [[South Georgia (island)\|South Georgia]] [[South Georgia and the South Sandwich Islands#South Sandwich Islands\|South Sandwich Islands]] }}`{=mediawiki} ### South of 60°S latitude {#south_of_60s_latitude}	2025-06-20T00:00:00
2,928	Association for Computing Machinery	The Association for Computing Machinery (ACM) is a US-based international learned society for computing. It was founded in 1947 and is the world\'s largest scientific and educational computing society. The ACM is a non-profit professional membership group, reporting nearly 110,000 student and professional members `{{as of\|2022\|lc=y}}`{=mediawiki}. Its headquarters are in New York City. The ACM is an umbrella organization for academic and scholarly interests in computer science (informatics). Its motto is \"Advancing Computing as a Science & Profession\". ## History In 1947, a notice was sent to various people:`{{r\|robertson}}`{=mediawiki} > On January 10, 1947, at the Symposium on Large-Scale Digital Calculating Machinery at the Harvard computation Laboratory, Professor Samuel H. Caldwell of Massachusetts Institute of Technology spoke of the need for an association of those interested in computing machinery, and of the need for communication between them. \[\...\] After making some inquiries during May and June, we believe there is ample interest to start an informal association of many of those interested in the new machinery for computing and reasoning. Since there has to be a beginning, we are acting as a temporary committee to start such an association:\ > \ > :E. C. Berkeley, Prudential Insurance Co. of America, Newark, N. J. > > : R. V. D. Campbell, Raytheon Manufacturing Co., Waltham, Mass. > : , Bureau of Standards, Washington, D.C. > : H. E. Goheen, Office of Naval Research, Boston, Mass. > : J. W. Mauchly, Electronic Control Co., Philadelphia, Pa. > : T. K. Sharpless, Moore School of Elec. Eng., Philadelphia, Pa. > : R. Taylor, Mass. Inst. of Tech., Cambridge, Mass. > : C. B. Tompkins, Engineering Research Associates, Washington, D.C. The committee (except for Curtiss) had gained experience with computers during World War II: Berkeley, Campbell, and Goheen helped build Harvard Mark I under Howard H. Aiken, Mauchly and Sharpless were involved in building ENIAC, Tompkins had used \"the secret Navy code-breaking machines\", and Taylor had worked on Bush\'s Differential analyzers. The ACM was then founded in 1947 under the name Eastern Association for Computing Machinery, which was changed the following year to the Association for Computing Machinery. The ACM History Committee since 2016 has published the A.M.Turing Oral History project, the ACM Key Award Winners Video Series, and the India Industry Leaders Video project. ## Activities ACM is organized into over 180 local professional chapters and 38 Special Interest Groups (SIGs), through which it conducts most of its activities. Additionally, there are over 680 student chapters. The first student chapter was founded in 1961 at the University of Louisiana at Lafayette. Many of the SIGs, such as SIGGRAPH, SIGDA, SIGPLAN, SIGCSE and SIGCOMM, sponsor regular conferences, which have become famous as the dominant venue for presenting innovations in certain fields. The groups also publish a large number of specialized journals, magazines, and newsletters. ACM also sponsors other computer science related events such as the worldwide ACM International Collegiate Programming Contest (ICPC), and has sponsored some other events such as the chess match between Garry Kasparov and the IBM Deep Blue computer. ## Services ### Publications ACM publishes over 50 journals including the prestigious Journal of the ACM, and two general magazines for computer professionals, Communications of the ACM (also known as Communications or CACM) and Queue. Other publications of the ACM include: - ACM XRDS, formerly \"Crossroads\", was redesigned in 2010 and is the most popular student computing magazine in the US. - ACM Interactions, an interdisciplinary HCI publication focused on the connections between experiences, people and technology, and the third largest ACM publication. - ACM Computing Surveys (CSUR) - Computers in Entertainment (CIE) - ACM Journal on Emerging Technologies in Computing Systems (JETC) - ACM Special Interest Group: Computers and Society (SIGCAS) - A number of journals, specific to subfields of computer science, titled ACM Transactions. Some of the more notable transactions include: - ACM Transactions on Algorithms (TALG) - ACM Transactions on Embedded Computing Systems (TECS) - ACM Transactions on Computer Systems (TOCS) - IEEE/ACM Transactions on Computational Biology and Bioinformatics (TCBB) - ACM Transactions on Computational Logic (TOCL) - ACM Transactions on Computer-Human Interaction (TOCHI) - ACM Transactions on Database Systems (TODS) - ACM Transactions on Graphics (TOG) - ACM Transactions on Mathematical Software (TOMS) - ACM Transactions on Multimedia Computing, Communications, and Applications (TOMM) - IEEE/ACM Transactions on Networking (TON) - ACM Transactions on Programming Languages and Systems (TOPLAS) - Games: Research and Practice Although Communications no longer publishes primary research and is not considered a prestigious venue, many of the great debates and results in computing history have been published in its pages. ACM has made almost all of its publications available to paid subscribers online at its Digital Library and also has a Guide to Computing Literature. ACM also offers insurance, online courses, and other services to its members. In 1997, ACM Press published Wizards and Their Wonders: Portraits in Computing (`{{ISBN\|0897919602}}`{=mediawiki}), written by Christopher Morgan, with new photographs by Louis Fabian Bachrach. The book is a collection of historic and current portrait photographs of figures from the computer industry. ### Portal and Digital Library {#portal_and_digital_library} The ACM Portal is an online service of the ACM. Its core are two main sections: ACM Digital Library and the ACM Guide to Computing Literature. The ACM Digital Library was launched in October 1997. It is the full-text collection of all articles published by the ACM in its articles, magazines and conference proceedings. The Guide is a bibliography in computing with over one million entries. The ACM Digital Library contains a comprehensive archive starting in the 1950s of the organization\'s journals, magazines, newsletters and conference proceedings. Online services include a forum called Ubiquity and Tech News digest. There is an extensive underlying bibliographic database containing key works of all genres from all major publishers of computing literature. This secondary database is a rich discovery service known as The ACM Guide to Computing Literature. ACM adopted a hybrid Open Access (OA) publishing model in 2013. Authors who do not choose to pay the OA fee must grant ACM publishing rights by either a copyright transfer agreement or a publishing license agreement. ACM was a \"green\" publisher before the term was invented. Authors may post documents on their own websites and in their institutional repositories with a link back to the ACM Digital Library\'s permanently maintained Version of Record. All metadata in the Digital Library is open to the world, including abstracts, linked references and citing works, citation and usage statistics, as well as all functionality and services. Other than the free articles, the full-texts are accessed by subscription. In addition, starting on April 7, 2022, ACM made its publications from 1951 to 2000 open access through the Digital Library in celebration of the 75th anniversary of the organization\'s founding. In 2020, ACM launched a major push to become a fully open access publisher by 2026. ACM restructured its pricing for the ACM Digital Library on the basis of publishing activity by affiliated lead authors in ACM\'s journals, magazines, and conference proceedings. Under this model, termed \"ACM Open,\" institutions pay set fees for full access to ACM Digital Library contents as well as unlimited open access publishing by their affiliated authors. Authors not affiliated with a participating institution will be expected to pay an article processing charge. As of May 2024, ACM reported that more than 1,340 institutions worldwide had signed on for ACM Open, putting ACM at just over halfway to meeting its target of 2,500 participating institutions by 2026. ## Membership grades {#membership_grades} In addition to student and regular members, ACM has several advanced membership grades to recognize those with multiple years of membership and \"demonstrated performance that sets them apart from their peers\". The number of Fellows, Distinguished Members, and Senior Members cannot exceed 1%, 10%, and 25% of the total number of professional members, respectively. ### Fellows The ACM Fellows Program was established by Council of the Association for Computing Machinery in 1993 \"to recognize and honor outstanding ACM members for their achievements in computer science and information technology and for their significant contributions to the mission of the ACM.\" There are 1,310 Fellows `{{as of\|2020\|lc=y}}`{=mediawiki} out of about 100,000 members. ### Distinguished Members {#distinguished_members} In 2006, ACM began recognizing two additional membership grades, one which was called Distinguished Members. Distinguished Members (Distinguished Engineers, Distinguished Scientists, and Distinguished Educators) have at least 15 years of professional experience and 5 years of continuous ACM membership and \"have made a significant impact on the computing field\". In 2006 when the Distinguished Members first came out, one of the three levels was called \"Distinguished Member\" and was changed about two years later to \"Distinguished Educator\". Those who already had the Distinguished Member title had their titles changed to one of the other three titles. List of Distinguished Members of the Association for Computing Machinery ### Senior Members {#senior_members} Also in 2006, ACM began recognizing Senior Members. According to the ACM, \"The Senior Members Grade recognizes those ACM members with at least 10 years of professional experience and 5 years of continuous Professional Membership who have demonstrated performance through technical leadership, and technical or professional contributions\". Senior membership also requires 3 letters of reference ### Distinguished Speakers {#distinguished_speakers} While not technically a membership grade, the ACM recognizes distinguished speakers on topics in computer science. A distinguished speaker is appointed for a three-year period. There are usually about 125 current distinguished speakers. The ACM website describes these people as \'Renowned International Thought Leaders\'. The distinguished speakers program (DSP) has been in existence for over 20 years and serves as an outreach program that brings renowned experts from Academia, Industry and Government to present on the topic of their expertise. The DSP is overseen by a committee ## Chapters ACM has three kinds of chapters: Special Interest Groups, Professional Chapters, and Student Chapters. , ACM has professional & SIG Chapters in 56 countries. , there exist ACM student chapters in 41 countries. ### Special Interest Groups {#special_interest_groups} - SIGACCESS: Accessible Computing - SIGACT: Algorithms and Computation Theory - SIGAda: Ada Programming Language - SIGAI: Artificial Intelligence - SIGAPP: Applied Computing - SIGARCH: Computer Architecture - SIGBED: Embedded Systems - SIGBio: Bioinformatics - SIGCAS: Computers and Society - SIGCHI: Computer--Human Interaction - SIGCOMM: Data Communication - SIGCSE: Computer Science Education - SIGDA: Design Automation - SIGDOC: Design of Communication - SIGecom: Electronic Commerce - SIGEVO: Genetic and Evolutionary Computation - SIGGRAPH: Computer Graphics and Interactive Techniques - SIGHPC: High Performance Computing - SIGIR: Information Retrieval - SIGITE: Information Technology Education - SIGKDD: Knowledge Discovery and Data Mining - SIGLOG: Logic and Computation ` ` - SIGMETRICS: Measurement and Evaluation - SIGMICRO: Microarchitecture - SIGMIS: Management Information Systems - SIGMM: Multimedia - SIGMOBILE: Mobility of Systems, Users, Data and Computing - SIGMOD: Management of Data - SIGOPS: Operating Systems - SIGPLAN: Programming Languages - SIGSAC: Security, Audit, and Control - SIGSAM: Symbolic and Algebraic Manipulation - SIGSIM: Simulation and Modeling - SIGSOFT: Software Engineering - SIGSPATIAL: Spatial Information - SIGUCCS: University and College Computing Services - SIGWEB: Hypertext, Hypermedia, and Web ## Conferences ACM and its Special Interest Groups (SIGs) sponsors numerous conferences worldwide. Most of the SIGs also have an annual conference. ACM conferences are often very popular publishing venues and are therefore very competitive. For example, SIGGRAPH 2007 attracted about 30000 attendees, while CIKM 2005 and RecSys 2022 had paper acceptance rates of only accepted 15% and 17% respectively. - AIES: Conference on AI, Ethics, and Society - ASPLOS: International Conference on Architectural Support for Programming Languages and Operating Systems - CHI: Conference on Human Factors in Computing Systems - CIKM: Conference on Information and Knowledge Management - COMPASS: International Conference on Computing and Sustainable Societies - DAC: Design Automation Conference - DEBS: Distributed Event Based Systems - FAccT: Conference on Fairness, Accountability, and Transparency - FCRC: Federated Computing Research Conference - GECCO: Genetic and Evolutionary Computation Conference - HT: Hypertext: Conference on Hypertext and Hypermedia - JCDL: Joint Conference on Digital Libraries - MobiHoc: International Symposium on Mobile Ad Hoc Networking and Computing - SC: Supercomputing Conference - SIGCOMM: ACM SIGCOMM Conference - SIGCSE: SIGCSE Technical Symposium on Computer Science Education - SIGGRAPH: International Conference on Computer Graphics and Interactive Techniques - RecSys: ACM Conference on Recommender Systems - TAPIA: Richard Tapia Celebration of Diversity in Computing Conference The ACM is a co--presenter and founding partner of the Grace Hopper Celebration of Women in Computing (GHC) with the Anita Borg Institute for Women and Technology. Some conferences are hosted by ACM student branches; this includes Reflections Projections, which is hosted by UIUC ACM. In addition, ACM sponsors regional conferences. Regional conferences facilitate increased opportunities for collaboration between nearby institutions and they are well attended. For additional non-ACM conferences, see this list of computer science conferences. ## Awards The ACM presents or co--presents a number of awards for outstanding technical and professional achievements and contributions in computer science and information technology. `{{div col\|colwidth=30em}}`{=mediawiki} - ACM A. M. Turing Award - ACM -- AAAI Allen Newell Award - ACM Athena Lecturer Award - ACM/CSTA Cutler-Bell Prize in High School Computing - ACM Distinguished Service Award - ACM Doctoral Dissertation Award - ACM Eugene L. Lawler Award - ACM Fellowship, awarded annually since 1993 - ACM Gordon Bell Prize - ACM Grace Murray Hopper Award - ACM -- IEEE CS George Michael Memorial HPC Fellowships - ACM -- IEEE CS Ken Kennedy Award - ACM -- IEEE Eckert--Mauchly Award - ACM India Doctoral Dissertation Award - ACM Karl V. Karlstrom Outstanding Educator Award - ACM Paris Kanellakis Theory and Practice Award - ACM Policy Award - ACM Presidential Award - ACM Prize in Computing (formerly: ACM -- Infosys Foundation Award in the Computing Sciences) - ACM Programming Systems and Languages Paper Award - ACM Student Research Competition - ACM Software System Award - International Science and Engineering Fair - Outstanding Contribution to ACM Award - SIAM/ACM Prize in Computational Science and Engineering Over 30 of ACM\'s Special Interest Groups also award individuals for their contributions with a few listed below. `{{div col\|colwidth=30em}}`{=mediawiki} - ACM Alan D. Berenbaum Distinguished Service Award - ACM Maurice Wilkes Award - ISCA Influential Paper Award ## Leadership The President of ACM for 2022--2024 is Yannis Ioannidis, Professor at the National and Kapodistrian University of Athens. He is successor of Gabriele Kotsis (2020--2022), Professor at the Johannes Kepler University Linz; Cherri M. Pancake (2018--2020), professor emeritus at Oregon State University and Director of the Northwest Alliance for Computational Science and Engineering (NACSE); Vicki L. Hanson (2016--2018), Distinguished Professor at the Rochester Institute of Technology and visiting professor at the University of Dundee; Alexander L. Wolf (2014--2016), Dean of the Jack Baskin School of Engineering at the University of California, Santa Cruz; Vint Cerf (2012--2014), American computer scientist and Internet pioneer; Alain Chesnais (2010--2012); and Dame Wendy Hall of the University of Southampton, UK (2008--2010). ACM is led by a council consisting of the president, vice-president, treasurer, past president, SIG Governing Board Chair, Publications Board Chair, three representatives of the SIG Governing Board, and seven Members-At-Large. This institution is often referred to simply as \"Council\" in Communications of the ACM. ## Infrastructure ACM has numerous boards, committees, and task forces which run the organization: 1. ACM Council 2. ACM Executive Committee 3. Digital Library Board 4. Education Board l Practitioner Board l Publications Board `SIG Governing Boar``DEI`` Council`\ `ACM Technology Policy Council`\ `ACM Representatives to Other Organizations`\ `Computer Science Teachers Association` ## ACM Council on Women in Computing {#acm_council_on_women_in_computing} ACM-W, the ACM council on women in computing, supports, celebrates, and advocates internationally for the full engagement of women in computing. ACM--W\'s main programs are regional celebrations of women in computing, ACM-W chapters, and scholarships for women CS students to attend research conferences. In India and Europe these activities are overseen by ACM-W India and ACM-W Europe respectively. ACM-W collaborates with organizations such as the Anita Borg Institute, the National Center for Women & Information Technology (NCWIT), and Committee on the Status of Women in Computing Research (CRA-W). The ACM-W gives an annual Athena Lecturer Award to honor outstanding women researchers who have made fundamental contributions to computer science. This program began in 2006. Speakers are nominated by SIG officers. ## Partner organizations {#partner_organizations} ACM\'s primary partner has been the IEEE Computer Society (IEEE-CS), which is the largest subgroup of the Institute of Electrical and Electronics Engineers (IEEE). The IEEE focuses more on hardware and standardization issues than theoretical computer science, but there is considerable overlap with ACM\'s agenda. They have many joint activities including conferences, publications and awards. ACM and its SIGs co-sponsor about 20 conferences each year with IEEE-CS and other parts of IEEE. Eckert--Mauchly Award and Ken Kennedy Award, both major awards in computer science, are given jointly by ACM and the IEEE-CS. They occasionally cooperate on projects like developing computing curricula. ACM has also jointly sponsored on events with other professional organizations like the Society for Industrial and Applied Mathematics (SIAM). ## Criticism In December 2019, the ACM co-signed a letter with over one hundred other publishers to President Donald Trump saying that an open access mandate would increase costs to taxpayers or researchers and hurt intellectual property. This was in response to rumors that he was considering issuing an executive order that would require federally funded research be made freely available online immediately after being published. It is unclear how these rumors started. Many ACM members opposed the letter, leading ACM to issue a statement clarifying that they remained committed to open access, and they wanted to see communication with stakeholders about the potential mandate. The statement did not significantly assuage criticism from ACM members. The SoCG conference, while originally an ACM conference, parted ways with ACM in 2014 because of problems when organizing conferences abroad.	2025-06-20T00:00:00
2,936	Southeast Alaska	Southeast Alaska, often abbreviated to southeast or southeastern, and sometimes called the Alaska(n)panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian province of British Columbia (and a small part of Yukon). The majority of southeast Alaska is situated in Tlingit Aaní, much of which is part of the Tongass National Forest, the United States\' largest national forest. In many places, the international border runs along the crest of the Boundary Ranges of the Coast Mountains (see Alaska boundary dispute). The region is noted for its scenery and mild, rainy climate. The largest cities in the region are Juneau, Sitka, and Ketchikan. This region is also home to Hyder, the easternmost town in Alaska. ## Geography Southeast Alaska has a land area of 35138 sqmi, comprising much of the Alexander Archipelago. The largest islands are, from North to South, Chichagof Island, Admiralty Island, Baranof Island, Kupreanof Island, Revillagigedo Island and Prince of Wales Island. Major bodies of water of southeast Alaska include Glacier Bay, Lynn Canal, Icy Strait, Chatham Strait, Stephens Passage, Frederick Sound, Sumner Strait, and Clarence Strait. The archipelago is the northern terminus of the Inside Passage, a protected waterway of convoluted passages between islands and fjords, beginning in Puget Sound in Washington state. This was an important travel corridor for Tlingit, Haida, and Tsimshian Native peoples, as well as gold-rush era steamships. In modern times it is an important route for Alaska Marine Highway ferries as well as cruise ships. ## Demographics Southeast Alaska includes seven entire boroughs and two census areas, in addition to the portion of the Yakutat Borough lying east of 141° West longitude. Although it has only 6.14 percent of Alaska\'s land area, it is larger than the state of Maine, and almost as large as the state of Indiana. The southeast Alaskan coast is roughly as long as the west coast of Canada. The 2010 census population of southeast Alaska was 71,616 inhabitants, representing approximately 10% of the state\'s total population. About 45% of residents in the southeast Alaska region were concentrated in the city of Juneau, the state capital. As of 2018, the number of settlements in southeast Alaska that have a population of at least 1,000 people has grown to nine. ### Boroughs - Haines Borough - Hoonah-Angoon Census Area - Juneau Borough - Ketchikan Gateway Borough - Petersburg Borough - Prince of Wales-Hyder Census Area - Sitka Borough - Skagway Borough - Wrangell Borough - Yakutat Borough (the part east of 141° W longitude; 12,506.53 km2, or about 63.12 percent of the borough) ### Major cities and towns {#major_cities_and_towns} Populations are taken from the 2020 census. - Juneau - 32,255 inhabitants - Sitka - 8,458 inhabitants - Ketchikan - 8,192 inhabitants - Petersburg - 3,043 inhabitants - Wrangell - 2,127 inhabitants - Haines - 1,657 inhabitants - Metlakatla - 1,454 inhabitants - Skagway - 1,240 inhabitants - Craig - 1,036 inhabitants ## National protected areas {#national_protected_areas} Southeast Alaska includes the Tongass National Forest (which manages Admiralty Island National Monument and Misty Fjords National Monument), Glacier Bay National Park, and Sitka National Historical Park. Glacier Bay is the sixth largest national park in the United States. On August 20, 1902, President Theodore Roosevelt established the Alexander Archipelago Forest Reserve, which formed the heart of the Tongass National Forest that covers most of the region. - Glacier Bay National Park and Preserve - Klondike Gold Rush National Historical Park - Sitka National Historical Park - Wrangell--St. Elias National Park and Preserve (part, the most southeastern section only) - Admiralty Island National Monument - Misty Fjords National Monument ## Climate The climate of southeast Alaska is dominated by a mid-latitude oceanic climate (Köppen Cfb) in the south, an oceanic, marine sub-polar climate (Köppen Cfc) in the central region around Juneau, and a subarctic climate (Köppen Dfc) to the far northwest and the interior highlands of the archipelago. Southeast Alaska is also the only region in Alaska where the average daytime high temperature is above freezing during the winter months, except for in the southern parts of the Aleutian islands such as Unalaska. ## Ecology Southeast Alaska is a temperate rain forest within the Pacific temperate rain forest zone, as classified by the World Wildlife Fund\'s ecoregion system, which extends from northern California to Prince William Sound. The most common tree species are sitka spruce and western hemlock. Wildlife includes brown bears, black bears, endemic Alexander Archipelago wolf packs, Sitka black-tailed deer, humpback whales, orcas, five species of salmon, bald eagles, harlequin ducks, scoters, and marbled murrelets. The [Ecological Atlas of Southeast Alaska](https://indd.adobe.com/view/bb243dff-5852-44c5-bdf5-4b1be96bdc53), published by Audubon Alaska in 2016, offers an overview of the region\'s landscape, birds, wildlife, human uses, climate change, and more, synthesizing data from agencies and a variety of other sources. ## Culture This area is the traditional homeland of the Tlingit, and home of a historic settling of Haida as well as a modern settlement of Tsimshian. The region is closely connected to Seattle and the American Pacific Northwest economically and culturally. ## Industry Major industries in southeast Alaska include commercial fishing and tourism (primarily the cruise ship industry). ### Logging Logging has been an important industry in the past, but has been steadily declining with competition from other areas and the closure of the region\'s major pulp mills; the Alaska Forest Association described the situation as \"desperate\" in 2011. Its members include Alcan Forest Products (owned by Canadian Transpac Group, one of the top 5 log exporters in North America) and Viking Lumber, which is based in Craig, Alaska. Debates over whether to expand logging in the federally owned Tongass are not uncommon. ### Mining Mining remains important in the northern area with the Juneau mining district and Admiralty mining district hosting active mines as of 2015. Gold was discovered in 1880 and played an important part in the early history of the region. In the 2010s, mines increasingly began to be explored and eventually completed in neighboring British Columbia, upstream of important rivers such as the Unuk and the Stikine, which became known as the transboundary mining issue. In 2014, the dam breach at the Mount Polley mine focused attention on the issue, and an agreement between Canada and Alaska was drafted in 2015. The proposed Kerr Sulphurets Mitchell exploration is upstream of the Unuk. Mines upstream of the Stikine include the Red Chris, which is owned by the same company (Imperial Metals) as the Mount Polley mine. ### Healthcare Major hospitals include Bartlett Regional Hospital in Juneau and PeaceHealth Ketchikan Medical Center in Ketchikan. Southeast Alaska Regional Health Consortium runs healthcare facilities across 27 communities as of 2022, including hospitals in Sitka and Wrangell; although it originally served Native Americans only, it has expanded access and combined with other local facilities over time. ### Shipbuilding Due to the fishing and ferries in the region, ship building and maintenance are economically significant. Ketchikan hosts a shipbuilding yard owned by Vigor Industrial. ### Tourism Tourists visit southeast Alaska primarily in the summer, and most visit via cruise ships, which run from April 15 to October 30. In 2019, around 1.3 million people visited Alaska by cruise ship. The northbound Inside Passage cruise commonly starts from either Seattle or Vancouver, Canada and stops in various ports including Ketchikan, Juneau, and Skagway. One-way trips will end in Whittier or Seward. An alternative Gulf of Alaska cruise starts in Whittier (Anchorage) and also passes through southeast Alaska\'s Inside Passage. The cruise ship industry became prominent in the 1960s after cruise ship entrepreneur Stanley B. McDonald repurposed a transport ship named Princess Pat, founding Princess Cruises to do leisure cruises which expanded into southeast Alaska by 1969. The TV series The Love Boat was set on a Princess cruise and featured episodes in Alaska; it also helped to popularize cruising generally which helped it grow rapidly between 1977 and 1987. Prior to Princess cruises, Chuck West created a tourism agency in 1947 under the name Arctic Alaska Tours which was renamed Westours, which originally arranged trips for travelers on steamships. ## History The border between Alaska and the Canadian province of British Columbia was the subject of the Alaska boundary dispute, where the United States and the United Kingdom claimed different borderlines at the Alaskan panhandle. While the British foreign affairs were in favor of support of the Canadian argument, the event resulted in what was thought of as a betrayal, leading to alienation of the British from the new nation of Canada. ## Transportation Due to the extremely rugged, mountainous nature of Southeastern Alaska, almost all communities (with the exception of Hyder, Skagway, and Haines) have no road connections outside of their locale, so aircraft and boats are the major means of transport. The Alaska Marine Highway passes through this region. ### Air transportation {#air_transportation} Alaska Airlines is by far the largest air carrier in the region, with Juneau\'s Juneau International Airport serving as the aerial hub for all of southeast, and Ketchikan\'s Ketchikan International Airport serving as a secondary hub for southern southeast Alaska. Alaska\'s bush airlines and air taxis serve many of the smaller and more isolated communities and villages in the regions. Many communities are accessible by air only by floatplane, as proper runways are often difficult to construct on the steep island slopes. ### Marine transportation {#marine_transportation} Southeast Alaska is primarily served by the state-run Alaska Marine Highway, which links Skagway, Haines, Hoonah, Juneau, Sitka, Petersburg, Wrangell, Ketchikan and other outlying communities with Prince Rupert, BC and Bellingham, Washington; and secondarily by the Prince of Wales Island-based Inter-Island Ferry Authority, which provides the only scheduled passenger and auto ferry service to the island. A new Authority, the Rainforest Islands Ferry Authority, was created and in 2014 may possibly operate the North End route. The Authority would connect Coffman Cove with Wrangell and Petersburg. Small companies like Sitka-based Allen Marine and other independent operators in the Lynn Canal occasionally also offer marine passenger service. Ship traffic in the area is seasonally busy with cruise ships.	2025-06-20T00:00:00
2,938	Algemeen Nijmeegs Studentenblad	The *Algemeen Nijmeegs Studentenblad* is an independent student magazine for the Radboud University Nijmegen. Founded in 1985 by members of the local student union AKKU, it is now published by the Stichting Multimedia. ## Notable publications and controversies {#notable_publications_and_controversies} In 1989 ANS started to publish the monthly comic strip DirkJan, before it moved to SjoSji. The magazine has published controversial articles that attracted nation-wide media attention, such as on the benefits of marihuana consumption for studying. In 2010 the university refused to distribute the magazine among freshmen because it did not endorse the editorial.	2025-06-20T00:00:00
2,939	Interior Alaska	Interior Alaska is the central region of Alaska\'s territory, roughly bounded by the Alaska Range to the south and the Brooks Range to the north. It is largely wilderness. Mountains include Denali in the Alaska Range, the Wrangell Mountains, and the Ray Mountains. The native people of the interior are Alaskan Athabaskans. The largest city in the interior is Fairbanks, Alaska\'s second-largest city, in the Tanana Valley. Other towns include North Pole, just southeast of Fairbanks, Eagle, Tok, Glennallen, Delta Junction, Nenana, Anderson, Healy, and Cantwell. The interior region has an estimated population of 113,154. \_\_TOC\_\_ ## Climate Interior Alaska experiences extreme seasonal temperature variability. Winter temperatures in Fairbanks average −12 °F (−24 °C) and summer temperatures average +62 °F (+17 °C). Temperatures there have been recorded as low as −65 °F (−54 °C) in mid-winter, and as high as +99 °F (+37 °C) in summer. Both the highest and lowest temperature records for the state were set in the Interior, with 100 °F (38 °C) in Fort Yukon and −80 °F (−62 °C) in Prospect Creek. Temperatures within a given winter are highly variable as well; extended cold snaps of forty below zero can be followed by unseasonable warmth with temperatures above freezing due to chinook wind effects. Summers can be warm and dry for extended periods creating ideal fire weather conditions. Weak thunderstorms produce mostly dry lightning, sparking wildfires that are mostly left to burn themselves out as they are often far from populated areas. The 2004 season set a new record with over 6600000 acre burned. The average annual precipitation in Fairbanks is 11.3 inches (287 mm). Most of this comes in the form of snow during the winter. Most storms in the interior of Alaska originate in the Gulf of Alaska, south of the state, though these storms often have limited precipitation due to a rain shadow effect caused by the Alaska Range. On clear winter nights, the aurora borealis can often be seen in the sky. Like all subarctic regions, the months from May to July in the summer have no night, only a twilight during the night hours. The months of November to January have little daylight. Fairbanks receives an average 21 hours of daylight between May 10 and August 2 each summer, and an average of less than four hours of daylight between November 18 and January 24 each winter. The interior of Alaska is largely underlined by discontinuous permafrost, which grades to continuous permafrost as the Arctic Circle is approached. Image:Fires in Interior Alaska.jpg\\|Fires in Interior Alaska from July 7, 2009. Image:Hundreds of Thousands of Acres Burning in Interior Alaska (natural).jpg\\|The thick pall of smoke the fires were creating (August 2, 2009). Image:Hundreds of Thousands of Acres Burning in Interior Alaska.jpg\\|Visible, short wave and near-infrared image showing burned areas (brick red) and unburned vegetation (bright green) (August 2, 2009). {{#lst:Fairbanks, Alaska\\|weather box}} ## Alaska Natives {#alaska_natives} While the vast majority of indigenous Native people of Interior Alaska are Athabaskan, large Yup\'ik and Iñupiaq populations reside in Fairbanks. The federally recognized tribes of Interior Alaska: - Council of Athabascan Tribal Governments (CATG): Beaver Village, Birch Creek Tribe, Circle Native Community, Native Village of Fort Yukon, Native Village of Venetie Tribal Government (also known as Arctic Village and Village of Venetie). - Tanana Chiefs Conference (TCC): Allakaket Village, Alatna Village, Village of Anaktuvuk Pass, Chalkyitsik Village, Village of Dot Lake, Native Village of Eagle, Evansville Village (also known as Bettles Field), Galena Village (also known as Louden Village), Healy Lake Village, Hughes Village, Huslia Village, Village of Kaltag, Koyukuk Native Village, Manley Hot Springs Village, Native Village of Minto, Nenana Native Association, Nikolai Village (Edzeno' Native Council), Northway Village, Nulato Village, Rampart Village, Native Village of Ruby, Native Village of Stevens, Native Village of Tanacross, Telida Village, Native Village of Tetlin. - Tanana Tribal Council: Native Village of Tanana. - Other places in the Interior Service Area not Federally Recognized as Tribes: Alcan, Anderson, Big Delta, Canyon Village, Central, Chatanika, Chicken, Clear, Delta Junction, Fairbanks, Fox, Indian River, Kokrines, Lake Minchumina, Medfra, North Pole, Salcha, Tok, Toklat, Tolovana, Wiseman, Wood River.	2025-06-20T00:00:00
2,941	The Bush (Alaska)	In Alaska, the Bush typically refers to any region of the state that is not connected to the North American road network and does not have ready access to the state\'s ferry system. A large proportion of Alaska Native populations live in the Bush, often depending on subsistence hunting and fishing. Geographically, the Bush comprises the Alaska North Slope; Northwest Arctic; West, including the Baldwin and Seward Peninsulas; the Yukon-Kuskokwim Delta; Southwest Alaska; Bristol Bay; Alaska Peninsula; and remote areas of the Alaska Panhandle and Interior. Some of the hub communities in the bush, which typically can be reached by larger, commercial airplanes, include Bethel, Dillingham, King Salmon, Nome, Utqiagvik, Kodiak Island, Kotzebue, and Unalaska-Dutch Harbor. Most parts of Alaska that are off the road or ferry system can be reached by small bush airplanes. Travel between smaller communities or to and from hub communities is typically accomplished by snowmobiles, boats, or ATVs.	2025-06-20T00:00:00
2,943	Dual wield	Dual wielding or Macedonian shooting is the technique of using two weapons, one in each hand, for training or combat. It is not a common combat practice. Although historical records of dual wielding in war are limited, there are numerous weapon-based martial arts that involve the use of a pair of weapons. The use of a companion weapon is sometimes employed in European martial arts and fencing, such as a parrying dagger. Miyamoto Musashi, a Japanese swordsman and ronin, was said to have conceived of the idea of a particular style of swordsmanship involving the use of two swords. In terms of firearms, especially handguns, dual wielding is generally denounced by firearm enthusiasts due to its impracticality. Though using two handguns at the same time confers an advantage by allowing more ready ammunition, it is rarely done due to other aspects of weapons handling. Dual wielding, both with melee and ranged weapons, has been popularized by fictional works (film, television, and video games). ## History Dual wielding has not been used or mentioned much in military history, though it appears in weapon-based martial arts and fencing practices. The dimachaerus was a type of Roman gladiator that fought with two swords. Thus, an inscription from Lyon, France, mentions such a type of gladiator, here spelled dymacherus. The dimachaeri were equipped for close-combat fighting. A dimachaerus used a pair of siccae (curved scimitar) or gladius and used a fighting style adapted to both attack and defend with his weapons rather than a shield, as he was not equipped with one. The use of weapon combinations in each hand has been mentioned for close combat in western Europe during the Byzantine, Medieval, and Renaissance era. The use of a parrying dagger such as a main gauche along with a rapier is common in historical European martial arts. North American Indian tribes of the Atlantic northeast used a form involving a tomahawk in the primary hand and a knife in the secondary. It is practiced today as part of the modern Cree martial art Okichitaw. All the above-mentioned examples, involve either one long and one short weapon, or two short weapons. An example of a dual wield of two sabres is the Ukrainian cossack dance hopak. ### Asia During the campaign Muslim conquest in 6th to 7th century AD, Rashidun caliphate general Khalid ibn Walid was reported to favor wielding two broad swords, with one in each hand, during combat. Traditional schools of Japanese martial arts include dual wield techniques, particularly a style conceived by Miyamoto Musashi involving the katana and wakizashi, two-sword kenjutsu techniques he called Niten Ichi-ryū. Eskrima, the traditional martial arts of the Philippines teaches Doble Baston techniques involving the basic use of a pair of rattan sticks and also Espada y daga or Sword/Stick and Dagger. Okinawan martial arts have a method that uses a pair of sai. Chinese martial arts involve the use of a pair of butterfly swords and hook swords. Famed for his enormous strength, Dian Wei, a military general serving under the warlord Cao Cao in the late Eastern Han dynasty of China, excelled at wielding a pair of ji (a halberd-like weapon), each of which was said to weigh 40 jin. Chen An, a warlord who lived during the Jin dynasty (266--420) and Sixteen Kingdoms period, wielded a sword and a serpent spear in each hand, supposedly measuring at 7 chi and 1 zhang 8 chi respectively. During Ran Wei--Later Zhao war, Ran Min, emperor of the short-lived Ran Wei empire of China, wielded two weapons, one in each hand, and fought fiercely, inflicting many casualties on the Xianbei soldiers while mounted on the famous horse Zhu Long (\"Red Dragon\"). Gatka, a weapon-based martial art from the Punjab region, is known to use two sticks at a time. The Thailand weapon-based martial art Krabi Krabong involves the use of a separate Krabi in each hand. Kalaripayattu teaches advanced students to use either two sticks (of various sizes) or two daggers or two swords, simultaneously. ### Modern The use of a gun in each hand is often associated with the American Old West, mainly due to media portrayals. It was common for people in the era to carry two guns, but not to use them at the same time. The second gun served as a backup weapon, to be used only if the main one suffered a malfunction or was lost or emptied. However, there were several examples of gunmen in the West who used two pistols at the same time in their gunfights: - John Wesley Hardin killed a gunman named Benjamin Bradley who shot at him, by drawing both of his pistols and firing back. - The Mexican vaquero Augustine Chacon had several gunfights in which he was outnumbered by more than one gunman and prevailed by equipping himself with a revolver in each hand. - King Fisher once managed to kill three bandits in a shootout by pulling both of his pistols. - During the Four Dead in Five Seconds Gunfight, lawman Dallas Stoudenmire pulled both of his pistols as he ran out onto the street and killed one bystander and two other gunmen. - Jonathan R. Davis, a prospector during the California Gold Rush, was ambushed by thirteen outlaws while together with two of his comrades. One of his friends was killed and the other was mortally wounded during the ambush. Davis drew both of his revolvers and fired, killing seven of the bandits, and killing four more with his bowie knife, causing the final two to flee. Dual wielding two handguns has been popularized by film and television. ## Effectiveness MythBusters compared many firing stances, including having a gun in each hand, and found that, compared to the two-handed single-gun stance as a benchmark, only the one-handed shoulder-level stance with a single gun was comparable in terms of accuracy and speed. The ability to look down the sights of the gun was given as the main reason for this. In an episode the following year, they compared holding two guns and firing simultaneously---rather than alternating left and right shots---with holding one gun in the two-handed stance, and found that the results were in favor of using two guns and firing simultaneously. ## In media {#in_media} - The Teenage Mutant Ninja Turtles features dual wielding being done by Leonardo with two katana swords, Raphael with two sais, and Michelangelo with two nunchucks. Sometimes, their arch enemy Shredder dual wields with many weapons. - Princess Mononoke features Lady Eboshi dual wielding with a katana sword and a hairpin. - The Marvel Comics features dual wielding being done by Deadpool with two katana swords, Nightcrawler with two sabres, Elektra with two sais, and Black Widow with two pistols and two batons. - The DC Comics features Dick Grayson and Barbara Gordon dual wielding two bastons. - The Star Wars franchise features many characters dual wielding two lightsabers or more including Darth Vader, Ahsoka Tano, and General Grievous. Star Wars: The Clone Wars features Palpatine and his former apprentice Darth Maul dual wielding two lightsabers each. Also, characters dual wielding two blaster pistols include Jango Fett and Bo-Katan Kryze. - The Halo franchise allows dual-wielding weapons from Halo 2 and Halo 3 onwards. - The Chronicles of Narnia: The Lion, the Witch and the Wardrobe features the centaur general Oreius dual wielding two longswords, and also the oppressive White Witch doing the same. It also features the Minotaur general Otmin dual wielding a falchion sword and a battle axe. - Ip Man 3 features butterfly swords being dual wielded by Ip Man and Cheung Tin-chi. - The Hobbit and The Lord of the Rings features the wizard Gandalf dual wielding a magic staff and a mystic longsword. - The Mummy Returns features the adventurous Egyptologist Evelyn O\'Connell and the treacherous Anck-su-namun dual wielding two sais. - The Pirates of the Caribbean franchise features characters dual wielding two swords including Jack Sparrow, Will Turner, and Elizabeth Swann. - The martial arts film Crouching Tiger, Hidden Dragon features Michelle Yeoh as Yu Shu Lien dual wielding with a dao sword which split to two, and then with two hook swords. - The Three Musketeers features many characters dual fighting with rapiers and daggers. - Mighty Morphin Power Rangers features Tommy Oliver dual wielding a sword and a dagger. - Robin of Sherwood features Nasir, a Saracen assassin who dual wields two scimitars. - Avatar: The Last Airbender features dual wielding done by Zuko with two dao swords, Jet with two hook swords, Suki with two war fans, and Sokka with a machete along a club or a boomerang. - The Transformers features dual wielding being done by many characters including Optimus Prime and Optimus Primal with two swords. - Kung Fu Hustle features iron rings being dual wielded by the humble tailor of Pigsty Alley. - Power Rangers: Jungle Fury features dual wielding being done by Casey Rhodes with two nunchakus and also two dao-themed Shark Sabres, Theo Martin with two tonfas and then two tessan-themed Jungle Fans, and Camille with two sais. - The Marvel Cinematic Universe film Shang Chi and the Legend of the Ten Rings features the Ten Rings, which are dual wielded by Wenwu and his son Shang-Chi. - The musical version of The Lion King features Mufasa and his son Simba dual wielding two akrafena swords to fight. - Lara Croft, the heroine of the Tomb Raider franchise, dual wields two pistols. - Dante, the protagonist of the Devil May Cry series, dual wields two pistols, named Ebony and Ivory. - Kirito, the protagonist of Sword Art Online, is known for being able to wield two swords of a similar length at the same time. - Sora and Roxas of the Kingdom Hearts franchise have the ability to dual wield Keyblades.	2025-06-20T00:00:00
2,947	Anoa	Anoa, also known as dwarf buffalo and *sapiutan, are two species of the genus Bubalus, placed within the subgenus Anoa* and endemic to the island of Sulawesi in Indonesia: the mountain anoa (Bubalus quarlesi) and the lowland anoa (Bubalus depressicornis). Both live in undisturbed rainforests and are similar in appearance to miniature water buffaloes, weighing 150 -. \'Anoa\' itself is Celebic in origin cognate to words in other related Philippine languages in the same Austronesian family that name the common water buffalo (anwáng in Tagalog, nuáng in Ilocano, nuwang in Ifugaw etc.). Both species of anoa have been classified as endangered since the 1960s and the populations continue to decrease. Fewer than 5,000 animals of each species likely remain. Reasons for their decline include poaching for hides, horns, and meat by the local peoples and loss of habitat due to the advancement of settlement. Currently, poaching is the most serious factor in most areas. Anoa are most closely allied to the larger Asian buffaloes, showing the same reversal of the direction of the hair on their backs. The horns are peculiar for their upright direction and comparative straightness, although they have the same triangular section as in other buffaloes. White spots are sometimes present below the eyes and there may be white markings on the legs and back; the absence or presence of these white markings may be indicative of distinct races. The horns of the cows are very small. The nearest allies of the anoa appear to be certain extinct Asian buffaloes, the remains of which have been found in the Siwalik Hills of northern India. Imagery of anoas may be present in the oldest rock art known as of 2024. Both are found on the island of Sulawesi and the nearby island of Buton in Indonesia. They live singly or in pairs, rather than in herds like most cattle, except when the cows are about to give birth. Little is known about their life history as well. However, in captive individuals, they have a life expectancy of 20--30 years. The anoa take two to three years before they reach sexual maturity have one calf a year and have very rarely been seen to have more. Skulls of anoa cannot be accurately identified as to species, and there is likely hybridizing and interbreeding between the two in the zoo population. It is questioned as to whether the two species were different due to them occurring together in many different areas, as well as some interbreeding. A study of the mtDNA of ten specimens from different localities found a high mitochondrial genetic diversity between individuals identified as one or the other species, indicating support for recognition as two species. ## Species - The lowland anoa (Bubalus depressicornis) is a small bovid, standing barely over 90 cm at the shoulder. It is usually solitary, living in lowland forests, browsing on plants and understory. According to Groves (1969) the lowland anoa can be told apart from the other species by being larger, having a triangular horn cross-section, sparse as opposed to thick and woolly hair, and always having white markings on the face and legs. ```{=html} <!-- --> ``` - The mountain anoa (Bubalus quarlesi) is also known as Quarle\'s anoa and anoa pegunungan. Standing at 70 cm at the shoulder, it is even smaller than the lowland anoa and the smallest of all living wild cattle. They also have longer, woolier hair that moults every year, showing faint spots on the head, neck, and limbs. According to Groves (1969), the mountain anoa can be told apart from the other species by being smaller, having a round horn cross-section, thick and woolly hair, and sometimes having white markings on the face and legs. ## Distribution Both the lowland anoa (Bubalus depressicornis) and the mountain anoa (Bubalus quarlesi) are endemic to the islands of Sulawesi in Indonesia. Both species appear to occur in the same areas. Sulawesi is a unique area because roughly 61% of the species found there are endemic species, including both anoa species. ## Habitat Traditionally, a key difference between the two species is the altitude at which they occur. The mountain anoa can be found at higher elevations than its lowland counterpart and is found in the forests. The lowland anoa was said to spend its time in the lower elevation areas and is also found in forests. Since 2005, however, these differences do not seem to be accurate, both species occur in the same areas in the same habitats. ## Morphology The anoa have many physical characteristics of bovine relatives and are considered to be most closely related to the water buffalo, which was confirmed through DNA analysis. The physical characteristics of the two species are similar. The anoa is the smallest of the wild cattle species. When anoa are born, they have a set of thick, woolly fur that comes in many color variations ranging from yellow to brown. In adults, the fur is typically brown or black, and males tend to have darker variations. Hair thickness varies slightly between the two species based on elevation and distribution. In both species of anoa, horns are present in both males and females and are typically straight protuberances. Another defining characteristic of the anoa is an extremely thick hide underneath the thick fur. ## Conservation Both anoa species are endemic to the island of Sulawesi and are currently experiencing large declines in their populations. Knowledge of their decline has only recently been documented, however, and the villages and villagers lack the knowledge of how to help maintain or increase populations. The leading cause of their population decline is hunting by local villagers for meat, with habitat loss also being significant. One benefit of the lack of knowledge about the legal status of what they are doing is that villagers are open to communication with researchers on their harvests and hunting practices; where awareness of conservation issues has penetrated, villagers will lie about their activities. Logging is a large issue because both species prefer core forested habitats that are far away from humans and the influences that come with them. By logging, humans create much more fragmented habitats and, therefore, a decrease in the area where the anoa can breed and live. This habitat fragmentation also alters the natural mixing of populations of the anoa. This may lead to a loss in genetic diversity between the two species and, over time, could also lead to their decline.	2025-06-20T00:00:00
2,948	Agner Krarup Erlang	Erlang}} `{{Infobox person \| name = Agner Krarup Erlang \| image = Erlang.jpg \| image_size = 200px \| caption = \| birth_date = {{birth date text\|1 January 1878}} \| birth_place = Lønborg, [[Denmark]] \| death_date = {{death-date and age\|3 February 1929\|1 January 1878}} \| death_place = [[Copenhagen]], Denmark \| resting place = Sundby Kirkegård, København, Denmark{{r\|Hs2004}} \| occupation = [[Mathematician]], [[statistician]], and [[engineer]] \| alma_mater = [[University of Copenhagen]] \| spouse = \| parents = \| children = }}`{=mediawiki} Agner Krarup Erlang (1 January 1878 -- 3 February 1929) was a Danish mathematician, statistician and engineer, who invented the fields of traffic engineering`{{r\|Brockmeyer1948}}`{=mediawiki} and queueing theory. Erlang\'s 1909 paper, and subsequent papers over the decades, are regarded as containing some of most important concepts and techniques for queueing theory. By the time of his relatively early death at the age of 51, Erlang had created the field of telephone networks analysis. His early work in scrutinizing the use of local, exchange and trunk telephone line usage in a small community to understand the theoretical requirements of an efficient network led to the creation of the Erlang formula, which became a foundational element of modern telecommunications network studies. ## Life Erlang was born at Lønborg, near Tarm, in Jutland. He was the son of a schoolmaster, and a descendant of Thomas Fincke on his mother\'s side. At age 14, he passed the Preliminary Examination of the University of Copenhagen with distinction, after receiving dispensation to take it because he was younger than the usual minimum age. For the next two years he taught alongside his father.`{{r\|Brockmeyer1948\|p=10-12}}`{=mediawiki} A distant relative provided free board and lodging, and Erlang prepared for and took the University of Copenhagen entrance examination in 1896, and passed with distinction. He won a scholarship to the university and majored in mathematics, and also studied astronomy, physics and chemistry. He graduated in 1901 with an MA and over the next 7 years taught at several schools.`{{r\|Brockmeyer1948\|p=13}}`{=mediawiki} He maintained his interest in mathematics, and received an award for a paper that he submitted to the University of Copenhagen.`{{r\|Brockmeyer1948\|p=14}}`{=mediawiki} He was a member of the Danish Mathematicians\' Association (DMF) and through this met amateur mathematician Johan Jensen, the Chief Engineer of the Copenhagen Telephone Company (KTAS in Danish), an offshoot of the International Bell Telephone Company.`{{r\|Brockmeyer1948\|p=14}}`{=mediawiki} Erlang worked for the Copenhagen Telephone Company from 1908 for almost 20 years, until his death in Copenhagen after an abdominal operation.`{{r\|Brockmeyer1948\|p=19}}`{=mediawiki} He was an associate of the British Institution of Electrical Engineers.`{{r\|Brockmeyer1948\|p=18}}`{=mediawiki} ## Contributions While working for the CTC, Erlang was presented with the classic problem of determining how many circuits were needed to provide an acceptable telephone service. His thinking went further by finding how many telephone operators were needed to handle a given volume of calls. Most telephone exchanges then used human operators and cord boards to switch telephone calls by means of jack plugs.`{{r\|Achak2014}}`{=mediawiki} Out of necessity, Erlang was a hands-on researcher. He would conduct measurements and was prepared to climb into street manholes to do so.`{{r\|Brockmeyer1948\|p=17}}`{=mediawiki} He was also an expert in the history and calculation of the numerical tables of mathematical functions, particularly logarithms. He devised new calculation methods for certain forms of tables.`{{r\|Brockmeyer1948b\|pp=109-110}}`{=mediawiki} He developed his theory of telephone traffic over several years. His significant publications include: - 1909 -- \"The Theory of Probabilities and Telephone Conversations\", which proves that the Poisson distribution applies to random telephone traffic.`{{r\|Erlang1909\|Erlang1925\|Erlang1948a}}`{=mediawiki} - 1917 -- \"Solution of some Problems in the Theory of Probabilities of Significance in Automatic Telephone Exchanges\", which contains his classic formulae for call loss and waiting time.`{{r\|Erlang1917\|Erlang1948b}}`{=mediawiki} - 1920 -- \"Telephone waiting times\", which is Erlang\'s principal work on waiting times, assuming constant holding times.`{{r\|Erlang1920\|Erlang1948c}}`{=mediawiki} These and other notable papers were translated into English, French and German. His papers were prepared in a very brief style and can be difficult to understand without a background in the field. One Bell Telephone Laboratories researcher is said to have learned Danish to study them.`{{r\|Brockmeyer1948\|p=17}}`{=mediawiki} The British Post Office accepted his formula as the basis for calculating circuit facilities.`{{r\|Brockmeyer1948\|p=17}}`{=mediawiki} In 1946, the CCITT named the international unit of telephone traffic the \"erlang\".`{{r\|CCITT1946}}`{=mediawiki}`{{r\|Brockmeyer1948\|p=19-22}}`{=mediawiki} A statistical distribution and programming language listed below have also been named in his honour. Erlang also made an important contribution to physiologic modeling with the Krogh-Erlang capillary cylinder model describing oxygen supply to living tissue.`{{r\|Krogh1919}}`{=mediawiki}`{{r\|Larsen2021}}`{=mediawiki}	2025-06-20T00:00:00
2,950	Anyone Can Whistle	*Anyone Can Whistle* is a musical with music and lyrics by Stephen Sondheim, and a book by Arthur Laurents. Described as \"a satire on conformity and the insanity of the so-called sane,\" the show tells a story of an economically depressed town whose corrupt mayor decides to create a fake miracle in order to attract tourists. The phony miracle draws the attention of an emotionally inhibited nurse, a crowd of inmates from a local asylum, and a doctor with secrets of his own. Following a tryout period in Philadelphia, Anyone Can Whistle opened at the Majestic Theatre on Broadway on April 4, 1964. The show received widely varied reviews (including negative notices from the New York Times and the New York Herald Tribune), and closed after a run of twelve previews and nine performances. The show\'s original run marked the stage musical debut of Angela Lansbury. In the decades since its closing, Anyone Can Whistle has seen relatively few productions compared to other Sondheim musicals; notable productions include a 1995 concert version at Carnegie Hall, a pair of stagings in London and Los Angeles in 2003 that incorporated revisions, and a 2010 concert staging for the Encores! program at New York City Center. However, its score has become acclaimed as a part of Sondheim\'s canon, and songs such as the title tune (\"Anyone Can Whistle\"), \"Everybody Says Don\'t\", and \"There Won\'t Be Trumpets\" have been performed widely. ## Background The show was first announced in The New York Times on October 5, 1961: \"For the winter of 1962, \[Arthur Laurents\] is nurturing another musical project, The Natives Are Restless. The narrative and staging will be Mr. Laurent\'s handiwork; music and lyrics that of Stephen Sondheim. A meager description was furnished by Mr. Laurents, who refused to elaborate. Although the title might indicate otherwise, it is indigenous in content and contemporary in scope. No producer yet.\" No news of the show appeared until July 14, 1963, in an article in The New York Times about Kermit Bloomgarden, where it discussed the four shows he was producing for the coming season; two were maybes, two were definite. One of the latter was a Sondheim-Laurents musical (now named Side Show). In a letter to Bloomgarden, Laurents wrote, \"I beg you not to mention the money problems or any difficulties to Steve anymore. It depresses him terribly and makes it terribly difficult for him to work\...It is damn hard to concentrate\...when all the atmosphere is filled with gloom and forebodings about will the show get the money to go on?\...Spare him the gory details.\" This behavior was considered unusual for Laurents, who did not have a reputation for kindness. Sondheim discovered that Laurents hated doing backers\' auditions and he took over that responsibility, playing and singing more than 30. They found 115 investors to back the \$350,000 production, including Richard Rodgers and Sondheim\'s father. Eager to work with both Laurents and Sondheim, Angela Lansbury accepted the lead role as Mayoress Cora Hoover Hooper, despite her strong misgivings about the script and her ability to handle the score. Also signed were Lee Remick as Nurse Fay Apple and Harry Guardino as Hapgood. Laurents had wanted Barbra Streisand for the role of Fay, but she turned it down to star in Funny Girl. Following rehearsals in New York City, the company started pre-Broadway tryouts in Philadelphia from March 2 to 21, 1964. Laurents, ignoring criticism about the show\'s message being trite and its absurdist style difficult to comprehend, poured his energies into restaging rather than dealing with the crux of the problem. The show suffered further setbacks when supporting actor Henry Lascoe, who played Comptroller Schub, suffered a heart attack during the show\'s out-of-town tryout, and was replaced by Gabriel Dell. According to Sondheim, \"Lansbury was so insecure onstage, and unhappy with her performance, that we considered replacing her. Ironically, it soon became apparent that it had been Lascoe, an old pro\...who had made her feel like an amateur. The minute his much less confident understudy took over, she felt free to blossom, which she spectacularly did.\" Sondheim called the reviews \"humiliating\" and the audiences \"hostile.\" ## Productions After multiple revisions, the show opened on Broadway on April 4, 1964, at the Majestic Theatre, where it closed after 9 performances and 12 previews, unable to overcome negative notices from major papers such as the New York Times and the New York Herald Tribune. Scenic design was by William and Jean Eckart, costume design by Theoni V. Aldredge, and lighting design by Jules Fisher. Choreographer Herbert Ross received the show\'s sole Tony Award nomination. The show became a cult favorite, and a truncated recording by the original cast released by Columbia Records sold well among Sondheim fans and musical theater buffs. \"There Won\'t Be Trumpets,\" a song cut during previews, has become a favorite of cabaret performers. On April 8, 1995, a staged concert was held at Carnegie Hall in New York City as a benefit for the Gay Men\'s Health Crisis. The concert was recorded by Columbia Records, preserving for the first time musical passages and numbers not included on the recording by the original Broadway cast. For example, the cut song \"There\'s Always a Woman\" was included at this concert. Lansbury served as narrator, with Madeline Kahn as Cora, Bernadette Peters as Fay, and Scott Bakula as Hapgood. Additional cast included Chip Zien, Ken Page, and Harvey Evans, the only cast member from the original show to reprise his role. In 2003, Sony reissued the original Broadway cast recording on compact disc. Two revivals were staged that year: one in London at the Bridewell Theatre and one in Los Angeles at the Matrix Theatre. The Ravinia Festival presented a staged concert on August 26 and 27, 2005, with Audra McDonald (Fay), Michael Cerveris (Hapgood) and Patti LuPone (Cora). On January 11, 2008, Talk Is Free Theatre presented the Canadian professional premiere (in concert) at the Gryphon Theatre in Barrie, Ontario, with a fundraiser performance on January 13 at the Diesel Playhouse in Toronto, Ontario. It starred Adam Brazier as Hapgood, Kate Hennig as Cora, Blythe Wilson as Fay, and Richard Ouzounian as Narrator, who also served as director. Choreography was by Sam Strasfeld. Additional cast included Juan Chioran as Comptroller Schub, Jonathan Monro as Treasurer Cooley, and Mark Harapiak as Chief Magruder. Musical direction was provided by Wayne Gwillim. Encores! presented a staged concert from April 8 through April 11, 2010, with Sutton Foster as Nurse Fay Apple, Donna Murphy as Mayoress Cora Hoover Hooper, and Raul Esparza as Hapgood, with direction and choreography by Casey Nicholaw. The production was the second most attended in Encores! history, and Stephen Sondheim was present at the post-matinee talkback on April 10. A London production of Anyone can Whistle opened at the Jermyn Street Studio Theatre, London, in association with Primavera Productions, running from March 10, 2010, to April 17, 2010. The director is Tom Littler, with Musical Director Tom Attwood, and a cast that includes Issy van Randwyck (Mayoress), Rosalie Craig (Nurse Fay Apple) and David Ricardo-Pearce (Hapgood). Porchlight Music Theatre presented Anyone Can Whistle in 2013 as a part of \"Porchlight Revisits\" series, in which it staged three forgotten musicals per year. It was directed by Christopher Pazdernik and music directed by Aaron Benham. A new production directed by Phil Willmott opened at the Union Theatre in London, running from February 8 through March 11, 2017. A concert presentation of the show was presented by MasterVoices, under the direction and baton of Ted Sperling, on March 10, 2022, at Carnegie Hall in New York City. This production featured Vanessa Williams (Cora Hoover Hooper), Santino Fontana (J. Bowden Hapgood), Elizabeth Stanley (Fay Apple), Douglas Sills (Comptroller Schub), Eddie Cooper (Treasurer Cooley), and Michael Mulheren (Police Chief Magruder). Joanna Gleason served as the narrator for the event IN 2022, a new production of the show ran at the Southwark Playhouse in London under the direction of Georgie Rankcom, with musical direction by Natalie Pound and choreography by Lisa Stevens. The show\'s cast featured Alex Young as Cora Hoover Hooper, Chrystine Symone as Nurse Fay Apple, and Jordan Broatch as J. Bowden Hapgood. This production was the largest staged version of the show since its debut on Broadway in 1964. ## Plot ### Act One {#act_one} The story is set in an imaginary American town that has gone bankrupt. (Its former major industry was an unidentified product that never wore out. Everyone has one now, and no one needs a replacement.) The only place in town doing good business is the local mental asylum, known as \"The Cookie Jar\", whose inmates look much healthier than the disgruntled townspeople (\"I\'m Like the Bluebird\"). All the money is in the hands of Cora Hoover Hooper, the stylish, ruthless mayoress and her cronies`{{Snd}}`{=mediawiki}Comptroller Schub, Treasurer Cooley, and Police Chief Magruder. Cora appears carried in a litter by her backup singers, and admits that she can accept anything except unpopularity (\"Me and My Town\"). The scheming Comptroller Schub tells her that he has a plan to save her administration and the town, promising, \"It\'s unethical.\" He tells her to meet him at the rock on the edge of town. At the rock, a local mother, Mrs. Schroeder, tries to tell her child, Baby Joan, to come down from the rock, when Baby Joan licks it`{{Snd}}`{=mediawiki}and a spring of water begins flowing from it. The town instantly proclaims a miracle, and Cora and her council eagerly anticipate tourist dollars as they boast of the water\'s curative powers (\"Miracle Song\"). It is soon revealed to Cora that the miracle is a fake, controlled by a pump inside the rock. The only person in town who doubts the miracle is Fay Apple, a skeptical but idealistic young nurse from the Cookie Jar. She appears at the rock with all forty-nine of the inmates \-- or \"Cookies\" \-- in tow, intending to let them take some of the water. Schub realizes that if they drink the water and remain insane, people will discover the fraud. As he tries to stop Fay, the inmates mingle with the townspeople, until no one can guess who is who. Fay disappears and, hiding from the police, admits that she hopes for a hero to deliver the town from Cora and her lackeys (\"There Won\'t Be Trumpets\"). Cora arrives on the scene with the Cookie Jar\'s manager, Dr. Detmold, who says that Fay has taken the records to identify the inmates. He tells Cora that he is expecting a new assistant who might help them. At that moment a mysterious stranger, J. Bowden Hapgood, arrives asking for directions to the Cookie Jar. He is instantly taken for the new assistant. Asked to identify the missing Cookies, Hapgood begins questioning random people and sorting them into two groups, group A, and group one, without divulging which group is the sane one. The town council becomes suspicious, but Hapgood simply questions them until they begin to doubt their own sanity. Cora is too caught up with his logic to care (\"Simple\"). As the extended musical sequence ends, the lights black out except for a spotlight on Hapgood, who announces to the audience, \"You are all mad!\" Seconds later, the stage lights are restored, and the cast is revealed in theater seats, holding programs, applauding the audience, as the act ends. ### Act Two {#act_two} The two groups are now in a bitter rivalry over which is the sane group (\"A-1 March\"). Another stranger, a French woman in a feathered coat appears. It is really Fay Apple in disguise. She introduces herself as the Lady from Lourdes, a professional Miracle Inspector, who has come to investigate the miracle. As Schub runs off to warn Cora, Fay seeks out Hapgood in his hotel, and the two seduce each other in the style of a French romantic film (\"Come Play Wiz Me\"). Fay tries to get Hapgood\'s help in exposing the miracle. Hapgood, however, sees through her disguise and wants to question her first. Fay refuses to take her wig off and confesses to him that this disguise, leftover from a college play, is the only way she can break out of her shell. She begins to hope, however, that Hapgood may be the one who can help her learn to be free (\"Anyone Can Whistle\"). Meanwhile, the two groups continue to march, and Cora, trying to give a speech, realizes that Hapgood has stolen her limelight (\"A Parade in Town\"). She and Schub plan an emergency meeting at her house. Back at the hotel, Hapgood comes up with an idea, telling Fay to destroy the Cookies\' records, so both they and Fay can be free. When Fay is reluctant, Hapgood produces a record of his own`{{Snd}}`{=mediawiki}he is her fiftieth Cookie. He is a practicing idealist who, after years of attempted heroism, is tired of crusading and has come to the Cookie Jar to retire. Inspired by his record, Fay begins to tear the records up. As she does, the Cookies appear and begin to dance (\"Everybody Says Don\'t\"). ### Act Three {#act_three} Cora is at her house with her council. Schub has put the miracle on hiatus but announces that they can easily pin the blame on Hapgood. The group celebrates their alliance (\"I\'ve Got You to Lean On\"). A mob forms outside the hotel, and Hapgood and Fay, still disguised, take refuge under the rock. Discovering the fraud, Cora and the council confront them. At that moment, Cora receives a telegram from the governor warning that if the quota of 49 cookies is not filled, she will be impeached. Schub tells her that since Hapgood never said who is sane or not, they can arrest anyone at random until the quota is filled. Hapgood refuses to help Fay stop the Mayoress since he has given up crusading. Although she knows she still isn\'t out of her shell, Fay angrily swears to go it alone (\"See What it Gets You\"). As Cora and the police force begin rounding up Cookies, Fay tries to get the key to the wagon from the guards in an extended ballet sequence (\"The Cookie Chase\"). As it ends, Fay is captured, and Dr. Detmold recognizes her. Fay tells the townspeople about the fake miracle, but the town refuses to believe her. Detmold tells Cora that even without the records, Fay can identify the inmates from memory. Cora warns that she will arrest forty-nine people, normal or not, and Fay, helplessly, identifies all the Cookies, except Hapgood. She tells him the world needs people like him, and Hapgood can\'t turn himself in. He asks Fay to come with him, but she still can\'t bring herself to break free. They regretfully part ways (\"With So Little to Be Sure Of\"). Word comes of a new miracle from the town beyond the valley, of a statue with a warm heart, and the townspeople, including Magruder and Cooley, rush off to see if it is real. Soon the town is all but deserted, and Cora is alone again. Again, Schub has the answer`{{Snd}}`{=mediawiki}they can turn the entire town into one big Cookie Jar. Cora realizes she and Schub are meant for each other, and they dance off together. As Fay resumes work, Detmold\'s real new assistant Jane Borden Osgood arrives, and Fay is horrified to realize that she is even more rigid and disbelieving than Fay herself, and the new nurse marches the Cookies off to the next town to disprove the new miracle. Horrified at seeing what she might become, Fay returns to the rock calling for Hapgood. When he doesn\'t answer, she tries to whistle`{{Snd}}`{=mediawiki}and succeeds in blowing a shrill, ugly whistle. Hapgood appears again, saying, \"That\'s good enough for me.\" As they embrace, the water begins flowing from the rock`{{Snd}}`{=mediawiki}a true miracle this time (\"Finale\"). ## Notable casts {#notable_casts} Character Broadway Off-Off-Broadway British Premiere Carnegie Hall Concert Encores! Carnegie Hall Revival Off-West End ----------------------- ---------------------------------------------------------------- --------------------------------------------------------------------- ----------------------------------------------------------------- ------------------------------------------------------------------------ --------------------------------------------------------------- ----------------------- ------------------ 1964 1980 1986 1995 2010 2022 Cora Hoover Hooper Angela Lansbury Gaylea Byrne Pip Hinton Madeline Kahn Donna Murphy Vanessa Williams Alex Young Fay Apple Lee Remick Rosemary McNamara Marilyn Curtis Bernadette Peters Sutton Foster Elizabeth Stanley Chrystine Symone J. Bowden Hapgood Harry Guardino Gary Krawford Michael Jayes Scott Bakula Raúl Esparza Santino Fontana Jordan Broatch Comptroller Schub Gabriel Dell Sam Stoneburner Bill Bradley Walter Bobbie Edward Hibbert Douglas Sills Danny Lane Treasurer Cooley Arnold Soboloff Ralph David Westfall John Griffiths Chip Zien Jeff Blumenkrantz Eddie Cooper Samuel Clifford Police Chief Magruder James Frawley David Berk Jonathan Stephens Ken Page John Ellison Conlee Michael Mulheren Renan Teodoro Mrs. Schroeder Peg Murray Ileane Gudell Hilary Cromie Maureen Moore Linda Griffin Colleen Brown Kathryn Akin Dr. Detmold Don Doherty Kermit Brown Thom Booker Nick Wyman Patrick Wetzel ??? Nathan Taylor Cora\'s Boys Sterling Clark, Harvey Evans, Larry Roquemore and Tucker Smith Stephan DeGhelder, Bill Hastings, Stephen Hope and David E. Mallard Michael Gyngell, Dermot McLaughlin, Alan Mosley, Neil Patterson Sterling Clark, Harvey Evans, Evan Pappas, Eric Riley and Tony Stevens Clyde Alves, Grasan Kingsbury, Eric Sciotto and Anthony Wayne ??? ## Musical numbers {#musical_numbers} (from the Broadway production) `{{col-begin}}`{=mediawiki} `{{col-3}}`{=mediawiki} Act I - Prelude Act I (instrumental) --- Orchestra - I\'m Like the Bluebird --- Company - Me and My Town --- Cora Hoover Hooper and Boys - Miracle Song --- Cora, Treasurer Cooley, Townspeople, Tourists, and Pilgrims - There Won\'t Be Trumpets --- Fay Apple\* - Simple --- J. Bowden Hapgood and Company Act II - Prelude Act II (instrumental) --- Orchestra - A-1 March --- Company - Come Play Wiz Me --- Fay, Hapgood, and Boys - Anyone Can Whistle --- Fay - A Parade In Town --- Cora - Everybody Says Don\'t --- Hapgood - Don\'t Ballet (instrumental) --- Orchestra Act III - Prelude Act III (instrumental) --- Orchestra - I\'ve Got You to Lean On --- Cora, Comptroller Schub, Treasurer Cooley, Chief Magruder, and Boys - See What It Gets You --- Fay - Anyone Can Whistle (Reprise) --- Fay - Cora\'s Chase (The Cookie Chase) --- Company - I\'m Like the Bluebird (Reprise 1) --- Cookies - With So Little to Be Sure Of --- Fay and Hapgood - I\'ve Got You to Lean On (Reprise) --- Cora and Schub\* - I\'m Like the Bluebird (Reprise 2) --- Cookies - Finale Ultimo (instrumental) --- Orchestra Notes - Asterisk (\) denotes song cut during Previews. - Despite being cut from the original production, \"There Won\'t Be Trumpets\" was nonetheless recorded for the original Broadway cast recording, though it remained unreleased until a 1989 remastered CD. Officially licensed scripts and scores now reinstate the song. - The 1995 concert production restored the songs \"There Won\'t Be Trumpets\" (Fay Apple) and \"There\'s Always a Woman\" (Fay and Cora), both previously cut. - \"Finale Ultimo\" is attached to the end of \"With So Little to Be Sure Of\" on the Original Cast Recording. ## Critical response {#critical_response} Howard Taubman in his The New York Times* review wrote that Laurents\'s \"book lacks the fantasy that would make the idea work, and his staging has not improved matters. Mr. Sondheim has written several pleasing songs but not enough of them to give the musical wings. The performers yell rather than talk and run rather than walk. The dancing is the cream.\" Steven Suskin wrote in his 2000 book about Broadway composers: The \"fascinating extended musical scenes, with extended choral work\... immediately marked Sondheim as the most distinctive theatre composer of his time. The first act sanity sequence\... and the third act chase\... are unlike anything that came before.\" Stuart King writing for London Box Office (April 2022) noted: \"Southwark Playhouse (with Guildford graduate Georgie Rankcom at the directorial helm for this gender-fluid production) has resurrected the piece for a short run --- just in time for Easter! But the burning question on Press Night was whether or not the cult 60s show would need a miracle to find a new, modern fan base, OR, have the subjects of political corruption, sexual identity and mental wellbeing potentially given the fundamentally flawed piece new meaning for a young and previously unfamiliar audience? This reviewer's answer would be that it will almost certainly depend entirely on who you are, how you identify (if indeed you bother with such matters), whether corruption in public office bothers you (why wouldn't it?) and probably most significantly of all, whether you consider yourself a Sondheim purist/aficionado/devotee.\" ## Awards and nominations {#awards_and_nominations} ### Original Broadway production {#original_broadway_production} +---------------------------------+----------------+--------------------------+--------------+--------+ \| Year \| Award ceremony \| Category \| Nominee \| Result \| +=================================+================+==========================+==============+========+ \| 1964 \| Tony Award \| Best Choreography \| Herbert Ross \| \| +---------------------------------+----------------+--------------------------+--------------+--------+	2025-06-20T00:00:00
2,952	Alcopop	An alcopop (or cooler) is a category of mixed alcoholic beverages with relatively low alcohol content (e.g., 3--7% alcohol by volume), including: 1. Malt beverages to which various fruit juices or other flavorings have been added 2. Wine coolers: beverages containing wine to which ingredients such as fruit juice or other flavorings have been added 3. Mixed drinks containing distilled alcohol and sweet liquids such as fruit juices or other flavourings The term alcopop (a portmanteau of the words alcohol and pop) is used commonly in the United Kingdom and Ireland to describe these drinks. In English-speaking Canada, \"cooler\" is more common but \"alcopop\" may also be used. Other terms include flavored alcoholic beverage (FAB), flavored malt beverage (FMB), \"pre-packaged\" or \"premium packaged\" spirit (PPS). In Australia and New Zealand \"premix\" and ready to drink (RTD) are both commonly used terms. \"Spirit cooler\" is used in South Africa for distilled alcohol versions. Hard seltzer is a related category of alcoholic drinks based on flavored seltzer water. Hard soda, meanwhile, is specifically related to soft drinks. Hard lemonade, which could be considered an alcopop, has been around for some time. Hard cider, on the other hand, is a fermented beverage similar to wine or beer. ## Description There are a variety of beverages produced and marketed around the world as well as within each market which are described as coolers or alcopops. They tend to be sweet and served in small bottles (typically 355 ml (the normal size of a soda pop can) in the US, 275 ml in South Africa and Germany, 330 ml in Canada and Europe), and between 4% and 7% ABV. In Europe, Canada, and South Africa coolers tend to be pre-mixed spirits, including vodka (e.g. Smirnoff Ice) or rum (e.g. Bacardi Breezer). In the United States, on the other hand, alcopops often start out as un-hopped beers, depending on the state in which they are sold. Much of the malt (and alcohol) is removed (leaving mostly water), with subsequent addition of alcohol (usually vodka or grain alcohol), sugar, coloring and flavoring. Such drinks are legally classified as beers in virtually all states and can therefore be sold in outlets that do not or cannot carry spirit-based drinks. There are, however, stronger ones that are simply pre-mixed spirits (e.g. Bacardi Rum Island Iced Tea), often containing about 12.5% alcohol by volume, that can be sold only where hard liquor is available. ## History Wine coolers gained popularity in the US market in the 1980s when Bartles and Jaymes began advertising their brand of wine coolers, which were followed by other brands, including when Bacardi introduced the Breezer. A growth in popularity occurred around 1993 with Two Dogs, DNA Alcoholic Spring Water, Hooper\'s Hooch and Zima, which was marketed under the title of \"malternative beverage.\" Wine coolers were on the decline due to the increase in the US federal wine tax, and using a malt-beverage base became the new industry standard. Later, Mike\'s Hard Lemonade was released in the United States, with humorous commercials depicting what they called \"violence against lemons\". Smirnoff also came out with another citrus-flavored malt beverage in the United States in the late 1990s called Smirnoff Ice, which promoted itself with flashy commercials, usually involving trendy young people dancing in unlikely situations and places. (In the UK, Smirnoff Ice is marketed by Diageo as a PPS.) Through its Alcopop-Free Zone® campaign, \" Alcohol Justice has sought to ban alcopop sales entirely since the sweet and brightly colored alcoholic drinks may appeal to children. Many cooler advertising campaigns have been criticized as trying to make alcopops appeal to young drinkers. In the United Kingdom, a media outcry during the mid-1990s arose as the tabloid press associated alcopops with under-age drinking which damaged sales and led to British liquor stores withdrawing them from their shelves. In response to a complaint from the Center for Science in the Public Interest (CSPI), the Federal Trade Commission (FTC) conducted an extensive investigation in 2001. The agency \"found no evidence of intent to target minors with FMB products, packaging, or advertising. Furthermore, after reviewing the consumer survey evidence submitted by CSPI in support of the proposition that FMBs were predominantly popular with minors, the FTC concluded that flaws in the survey\'s methodology limited the ability to draw conclusions from the survey data.\" The Federal Trade Commission again in 2003 investigated FMB ads, product placement, and internal company marketing documents after a directive from the conferees of the House and Senate Appropriations Committees. \"The Commission\'s investigation found no evidence of targeting underage consumers in the marketing of FMBs. Adults 21 to 29 appear to be the intended target of FMB marketing\" and found that \"the majority of FMB drinkers are over the age of 27.\" In December 2003, Ireland raised the tax on flavored malt beverages to equal that of spirits, the second-highest in Europe. Germany has imposed an extra duty of 0.80 to 0.90 euro per bottle effective August 1, 2004. To circumvent higher taxation, some German producers have switched to wine coolers, which are being marketed the same way. Some bottles now carry a warning stating that they are not for consumption by people under the legal drinking age (under 18 in the UK and 21 in the United States). On May 11, 2008, the Australian Government increased the excise tax on alcopops by 70%, to bring it in line with the tax on spirits. There is the concern this tax will encourage consumers to buy straight spirits and mix the drinks themselves, possibly resulting in drinks with a higher alcohol concentration than the premixed alternatives. This tax was revoked during March 2009 meaning the government had to pay back the 290 million collected on the tax. The Federal Trade Commission report states, \"Further, industry-conducted research on consumers over the age of 21 who use FMBs shows that these consumers generally view the FMBs as substitutes for beer, \... This research also concludes that consumers are not likely to consume more than two or three FMBs on any occasion because of the products\' sweetness. In March 2018, Coca-Cola announced it would be launching an alcopop product for the first time, a chūhai beverage in Japan. ## Brands Brands of coolers are numerous and their alcoholic base vary greatly. Some notable brands include: VK, Smirnoff Ice, Mike\'s Hard Lemonade, Bacardi Breezer, Palm Bay, Skyy Blue, Jack Daniel\'s mixed with Coca-Cola and, in the UK, WKD Original Vodka. Garage is an alcopop produced by the Finnish brewery Sinebrychoff. ## Health concerns {#health_concerns} Alcohol-based sugar-sweetened beverages like alcopop are closely linked to episodic drinking in adolescents. ## Attempts to discourage {#attempts_to_discourage} ### Australia The Australian government increased the tax on these drinks under the 2008 budget to the same rate as spirits, volumetrically, in an effort to stop binge drinking. The tax was criticized by the opposition as a tax grab, and voted down in the Senate on March 18, 2009. Before its rejection, the tax had already raised at least A\$290 million after April 2008. In April 2009, some Labor party MPs planned to resubmit the tax to the Senate, and it was finally approved in August 2009, increasing the tax on the drinks from \$39.36 to \$66.67 per litre of alcohol. A 2013 study concluded that the tax had no impact on binge drinking of the drinks by teenagers. ### Germany On 1 July 2004 the German government increased the tax on mixed drinks based on spirits (e.g. vodka, rum) by roughly one Euro per 275-ml-bottle in order to discourage teenagers drinking excessively, although those drinks were already prohibited for those under the age of 18. This had two implications: The most common alcopops, such as Smirnoff Ice or Bacardi Breezer, were nearly taken off the market, while other manufacturers changed the recipes of their drinks to replace spirit alcohols with wine or beer, but with the same ABV, enabling these mixed drinks (which are not \"alcopops\" under German law) to be sold legally to minors 16 and 17 years of age. ### Philippines In 2019, some senators including Pia Cayetano and former Special Assistant to the President Bong Go called for pullout of alcopops from the market due to \"deceptive packaging that resembles fruit juices usually bought by young consumers\". Alcopops also have seven percent alcohol content, which is slightly lower than that of local beer brand Red Horse Beer. ### Sweden Systembolaget blocked the sale of alcoholic soft drinks in Sweden until mid-1996, when Alkoholsortimentsnämnden decided, with reference to Treaty of Rome Article 30, that Systembolaget could not refuse to sell certain products. This led to great debate, where the marketing of the alcoholic soft drink was considered to be aimed above all at young people. After initially great sales successes, the popularity has now declined, and many of the alcoholic drinks\' market shares have been taken over by sweeter varieties of cider that share many characteristics with the soft drink but have been fermented to their alcoholic strength. ### United Kingdom {#united_kingdom} In June 1997, Co-op Food became the first major retailer to place an outright ban on the sale of alcopops in its shops. This has since been revoked.	2025-06-20T00:00:00
2,955	Alkali	In chemistry, an alkali (`{{IPAc-en\|ˈ\|æ\|l\|k\|ə\|l\|aɪ\|audio=LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-Alkali.wav}}`{=mediawiki}; from the Arabic word `{{transliteration\|ar\|al-qāly}}`{=mediawiki}, القالِي) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The adjective alkaline, and less often, alkalescent, is commonly used in English as a synonym for basic, especially for bases soluble in water. This broad use of the term is likely to have come about because alkalis were the first bases known to obey the Arrhenius definition of a base, and they are still among the most common bases. ## Etymology The word alkali is derived from Arabic al qalīy (or alkali), meaning `{{gloss\|the calcined ashes}}`{=mediawiki} (see calcination), referring to the original source of alkaline substances. A water-extract of burned plant ashes, called potash and composed mostly of potassium carbonate, was mildly basic. After heating this substance with calcium hydroxide (slaked lime), a far more strongly basic substance known as caustic potash (potassium hydroxide) was produced. Caustic potash was traditionally used in conjunction with animal fats to produce soft soaps, one of the caustic processes that rendered soaps from fats in the process of saponification, one known since antiquity. Plant potash lent the name to the element potassium, which was first derived from caustic potash, and also gave potassium its chemical symbol K (from the German name Kalium), which ultimately derived from alkali. ## Common properties of alkalis and bases {#common_properties_of_alkalis_and_bases} Alkalis are all Arrhenius bases, ones which form hydroxide ions (OH^−^) when dissolved in water. Common properties of alkaline aqueous solutions include: - Moderately concentrated solutions (over 10^−3^ M) have a pH of 10 or greater. This means that they will turn phenolphthalein from colorless to pink. - Concentrated solutions are caustic (causing chemical burns). - Alkaline solutions are slippery or soapy to the touch, due to the saponification of the fatty substances on the surface of the skin. - Alkalis are normally water-soluble, although some like barium carbonate are only soluble when reacting with an acidic aqueous solution. ## Difference between alkali and base {#difference_between_alkali_and_base} The terms \"base\" and \"alkali\" are often used interchangeably, particularly outside the context of chemistry and chemical engineering. There are various, more specific definitions for the concept of an alkali. Alkalis are usually defined as a subset of the bases. One of two subsets is commonly chosen. - A basic salt of an alkali metal or alkaline earth metal (this includes Mg(OH)~2~ (magnesium hydroxide) but excludes NH~3~ (ammonia)). - Any base that is soluble in water and forms hydroxide ions or the solution of a base in water. (This includes both Mg(OH)~2~ and NH~3~, which forms NH~4~OH.) The second subset of bases is also called an \"Arrhenius base\". ## Alkali salts {#alkali_salts} Alkali salts are soluble hydroxides of alkali metals and alkaline earth metals, of which common examples are: - Sodium hydroxide (NaOH) -- often called \"caustic soda\" - Potassium hydroxide (KOH) -- commonly called \"caustic potash\" - Lye -- generic term for either of two previous salts or their mixture - Calcium hydroxide (Ca(OH)~2~) -- saturated solution known as \"limewater\" - Magnesium hydroxide (Mg(OH)~2~) -- an atypical alkali since it has low solubility in water (although the dissolved portion is considered a strong base due to complete dissociation of its ions) ## Alkaline soil {#alkaline_soil} Soils with pH values that are higher than 7.3 are usually defined as being alkaline. These soils can occur naturally due to the presence of alkali salts. Although many plants do prefer slightly basic soil (including vegetables like cabbage and fodder like buffalo grass), most plants prefer mildly acidic soil (with pHs between 6.0 and 6.8), and alkaline soils can cause problems. ## Alkali lakes {#alkali_lakes} In alkali lakes (also called soda lakes), evaporation concentrates the naturally occurring carbonate salts, giving rise to an alkalic and often saline lake. Examples of alkali lakes: - Alkali Lake, Lake County, Oregon - Baldwin Lake, San Bernardino County, California - Bear Lake on the Utah--Idaho border - Lake Magadi in Kenya - Lake Turkana in Kenya - Mono Lake, near Owens Valley in California - Redberry Lake, Saskatchewan - Summer Lake, Lake County, Oregon - Tramping Lake, Saskatchewan	2025-06-20T00:00:00
2,957	AMOS (programming language)	AMOS BASIC is a dialect of the BASIC programming language for the Amiga computer. Following on from the successful STOS BASIC for the Atari ST, AMOS BASIC was written for the Amiga by François Lionet with Constantin Sotiropoulos and published by Europress Software in 1990. The language was notable for its focus on media and game development capabilities, allowing users to easily create demanding multimedia software and games. It featured full structured code and numerous high-level functions for loading and manipulating images, animations, and sounds. These capabilities made it a popular choice among Amiga enthusiasts, particularly beginners, for creating video games (especially platformers and graphical adventures), multimedia applications, and educational software. ## History AMOS competed on the Amiga platform with Acid Software\'s Blitz BASIC. Both BASICs differed from other dialects on different platforms, in that they allowed the easy creation of fairly demanding multimedia software, with full structured code and many high-level functions to load images, animations, sounds and display them in various ways. The original AMOS was a BASIC interpreter which, whilst working fine, suffered the same disadvantages of any language being run interpretively. By all accounts, AMOS was extremely fast among interpreted languages, being speedy enough that an extension called AMOS 3D could produce playable 3D games even on plain 7 MHz 68000 Amigas. Later, an AMOS compiler was developed that further increased speed. AMOS could also run MC68000 machine code, loaded into a program\'s memory banks. To simplify animation of sprites, AMOS included the AMOS Animation Language (AMAL), a compiled sprite scripting language which runs independently of the main AMOS BASIC program. It was also possible to control screen and \"rainbow\" effects using AMAL scripts. AMAL scripts in effect created CopperLists, small routines executed by the Amiga\'s Agnus chip. After the original version of AMOS, Europress released a compiler (AMOS Compiler), and two other versions of the language: Easy AMOS, a simpler version for beginners, and AMOS Professional, a more advanced version with added features, such as a better integrated development environment, ARexx support, a new user interface API and new flow control constructs. Neither of these new versions was significantly more popular than the original AMOS. AMOS was used mostly to make multimedia software, video games (platformers and graphical adventures) and educational software. The language was mildly successful within the Amiga community. Its ease of use made it especially attractive to beginners. One of AMOS BASIC\'s disadvantages, stemming from its Atari ST lineage, was its incompatibility with the Amiga\'s operating system functions and interfaces. Instead, AMOS BASIC controlled the computer directly, which caused programs written in it to have a non-standard user interface, and also caused compatibility problems with newer versions of hardware. Today, the language has declined in popularity along with the Amiga computer for which it was written. Despite this, a small community of enthusiasts are still using it. The source code to AMOS was released around 2001 under a BSD style license by Clickteam, a company that includes the original programmer. ## Software Software written using AMOS BASIC includes: - AQUABYSS by Aged Code, is a 2022 strategy trading game for the Amiga - Miggybyte - Scorched Tanks - Games by Vulcan Software, amongst which was the Valhalla trilogy - Amiga version of Ultimate Domain (called Genesia) by Microïds - Flight of the Amazon Queen, by Interactive Binary Illusions - Extreme Violence, included on an Amiga Power cover disk - Jetstrike, a commercial game by Rasputin Software - Black Dawn, a 1993 game for the Amiga personal computer	2025-06-20T00:00:00
2,959	Arcadia 2001	The Arcadia 2001 is a second-generation 8-bit home video game console released by Emerson Radio in May 1982 for a price of US\$99, several months before the release of ColecoVision. It was discontinued only 18 months later, with a total of 35 games having been released. Emerson licensed the Arcadia 2001 to Bandai, which released it in Japan. Over 30 Arcadia 2001 clones exist despite the system being a commercial failure. The unrelated Arcadia Corporation, manufacturer of the Supercharger add-on for the Atari 2600, was sued by Emerson for trademark infringement. Arcadia Corporation then changed its name to Starpath. ## Description The Arcadia is much smaller than its contemporary competitors and is powered by a standard 12 volt power supply so it can be used in a boat or a vehicle. It has two headphone jacks on the far left and right sides of the back. The system came with two Intellivision-style controllers with a 12-button keypad and \"fire\" buttons on the sides. The direction pads have a removable joystick attachment. Most games came with BoPET overlays that can be applied to the controller\'s keypads. The console itself has five buttons: Power, Start, Reset, Option, and Select. There are at least three different cartridge case styles and artwork, with variations on each. Emerson-family cartridges come in two different lengths (short and long) of black plastic cases. ## Technical specifications {#technical_specifications} - Main Processor: Signetics 2650 CPU (some variants run a Signetics 2650A) - RAM: 1 KB - ROM: None - Video display: 128 × 208 / 128 × 104, 8 Colours - Video display controller: Signetics 2637 UVI @ 3.58 MHz (NTSC), 3.55 MHz (PAL) - Sound: Single Channel \"Beeper\" + Single Channel \"Noise\" - Hardware Sprites: 4 independent, single color - Controllers: 2 × 2 way - Keypads: 2 × 12 button (more buttons on some variants) ## Console variants and clones {#console_variants_and_clones} Many variants and clones of the Arcadia 2001 have been released by various companies in different countries. These systems are mostly compatible with each other. In 1982, the Bandai Arcadia was released only in Japan. Four exclusive games were released for the system. +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Name \| Manufacturer \| Country \| Compatibility family \| Image \| +===========================================================+=======================+=============================================================================================================================================================================+======================+=======+ \| Advision Home Arcade \| Advision \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| 2001 ALTOS Home Video Centre \| Altos India Limited \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Arcadia \| Bandai \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Arcadia 2001 \| Emerson \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Cosmos \| Tele-Computer \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Dynavision \| Morning-Sun Commerce \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Educat \| unknown \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Ekusera \| P.I.C. \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Hanimex MPT-03 \| Hanimex \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| HMG-2650 \| Hanimex \| \ \| Emerson console \| \| \| \| \| `{{flagicon\|CAN}}`{=mediawiki}\ \| \| \| \| \| \| `{{flagicon\|AUS}}`{=mediawiki} \| \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Home Arcade Centre \| Hanimex \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Intelligent Game MPT-03 \| Intelligent Game \| \ \| MPT-03 console \| \| \| \| \| `{{flagicon\|CAN}}`{=mediawiki} \| \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Intercord XL 2000 System \| Intercord \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Intervision 2001 \| Intervision \| `{{flagicon\|FIN}}`{=mediawiki} \| Ormatu console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| ITMC MPT-03 \| ITMC \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Leisure Vision \| Leisure-Dynamics \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Leonardo \| GiG Electronics \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Home Entertainment Centre Ch-50 \| Inno-Hit \| \| Ormatu console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Ormatu 2001 \| Ormatu Electronics BV \| \| Ormatu console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Palladium Video-Computer-Game \| Neckermann \| \| Palladium console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Polybrain Video Computer Game \| Polybrain \| \| Palladium console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Poppy MPT-03 Tele Computer Spiel \| Poppy \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Prestige Video Computer Game MPT-03 \| Prestige \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Robdajet MPT-03 \| Robdajet \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Rowtron 2000 \| Rowtron \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Schmid TVG-2000 \| Schmid \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Sheen Home Video Centre 2001 \| Sheen \| \| Ormatu console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Soundic MPT-03 \| Soundic \| \ \| MPT-03 console \| \| \| \| \| `{{flagicon\|SGP}}`{=mediawiki}[1](https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes19820716-1.2.144.1?ST=1&AT=search&k=MPT-03&QT=mpt-03&oref=article) \| \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tedelex Home Arcade \| Tedelex \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Mr. Altus Das Tele-Gehirn Color (German for tele brain) \| HGS Electronic \| \| Palladium console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tele-Fever \| Tchibo \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tempest MPT-03 \| Tempest \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tobby MPT-03 \| Tobby \| ? \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Trakton Computer Video Game \| Trakton \| \| Palladium console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tryom Video Game Center \| Tryom \| \| MPT-03 console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Tunix Home Arcade \| Monaco Leisure \| \| Emerson console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| UVI Compu-Game \| Orbit Electronics \| \| Orbit console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ \| Video Master \| Grandstand \| \| Orbit console \| \| +-----------------------------------------------------------+-----------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------+-------+ ### Bandai Arcadia {#bandai_arcadia} In 1982, the Bandai Arcadia, a variant of the Emerson Arcadia 2001, was licensed and distributed to Japan by Bandai for a price of 19,800 yen. There were four Japan-exclusive games released by Bandai. - Doraemon - Dr. Slump - Mobile Suit Gundam - Super Dimension Fortress Macross ## Reception After seeing the Arcadia 2001 at the summer 1982 Consumer Electronics Show, Danny Goodman of Creative Computing Video & Arcade Games reported that its graphics were similar to the Atari 2600\'s, and that \"our overall impression of the game play was favorable for a system in this price range, though no cartridge stands out as being an exciting original creation\". He called the controller offering both Intellivision-like disc and joystick functionality \"A great idea\". ## Games Emerson planned to launch the console with 19 games.`{{r\|goodman1983spring}}`{=mediawiki} Some Arcadia 2001 games are ports of lesser-known arcade games such as Route 16, Jungler, and Jump Bug, which were not available on other home systems. Emerson actually created many popular arcade titles including Pac-Man, Galaxian and Defender for the Arcadia, but never had them manufactured as Atari started to sue its competitor companies for releasing games to which it had exclusive-rights agreements. Early marketing showed popular arcade games, but they were later released as clones. For instance, the Arcadia 2001 game Space Raiders is a clone of Defender, and Breakaway is a clone of Breakout. ### Released games {#released_games} There are 47 games known to have been released for the Arcadia 2001 and its clones. ### Bandai Arcadia Only {#bandai_arcadia_only} See here	2025-06-20T00:00:00
2,994	Anemometer	In meteorology, an anemometer (`{{etymology\|grc\|''{{wikt-lang\|grc\|άνεμος}}'' ({{grc-transl\|άνεμος}})\|wind\|\|''{{wikt-lang\|grc\|μέτρον}}'' ({{grc-transl\|μέτρον}})\|measure}}`{=mediawiki}) is a device that measures wind speed and direction. It is a common instrument used in weather stations. The earliest known description of an anemometer was by Italian architect and author Leon Battista Alberti (1404--1472) in 1450. ## History The anemometer has changed little since its development in the 15th century. Alberti is said to have invented it around 1450. In the ensuing centuries numerous others, including Robert Hooke (1635--1703), developed their own versions, with some mistakenly credited as its inventor. In 1846, Thomas Romney Robinson (1792--1882) improved the design by using four hemispherical cups and mechanical wheels. In 1926, Canadian meteorologist John Patterson (1872--1956) developed a three-cup anemometer, which was improved by Brevoort and Joiner in 1935. In 1991, Derek Weston added the ability to measure wind direction. In 1994, Andreas Pflitsch developed the sonic anemometer. ## Velocity anemometers {#velocity_anemometers} ### Cup anemometers {#cup_anemometers} A simple type of anemometer was invented in 1845 by Rev. Dr. John Thomas Romney Robinson of Armagh Observatory. It consisted of four hemispherical cups on horizontal arms mounted on a vertical shaft. The air flow past the cups in any horizontal direction turned the shaft at a rate roughly proportional to the wind\'s speed. Therefore, counting the shaft\'s revolutions over a set time interval produced a value proportional to the average wind speed for a wide range of speeds. This type of instrument is also called a rotational anemometer. #### Four cup {#four_cup} With a four-cup anemometer, the wind always has the hollow of one cup presented to it, and is blowing on the back of the opposing cup. Since a hollow hemisphere has a drag coefficient of .38 on the spherical side and 1.42 on the hollow side, more force is generated on the cup that presenting its hollow side to the wind. Because of this asymmetrical force, torque is generated on the anemometer\'s axis, causing it to spin. Theoretically, the anemometer\'s speed of rotation should be proportional to the wind speed because the force produced on an object is proportional to the speed of the gas or fluid flowing past it. However, in practice, other factors influence the rotational speed, including turbulence produced by the apparatus, increasing drag in opposition to the torque produced by the cups and support arms, and friction on the mount point. When Robinson first designed his anemometer, he asserted that the cups moved one-third of the speed of the wind, unaffected by cup size or arm length. This was apparently confirmed by some early independent experiments, but it was incorrect. Instead, the ratio of the speed of the wind and that of the cups, the anemometer factor, depends on the dimensions of the cups and arms, and can have a value between two and a little over three. Once the error was discovered, all previous experiments involving anemometers had to be repeated. #### Three cup {#three_cup} The three-cup anemometer developed by Canadian John Patterson in 1926, and subsequent cup improvements by Brevoort & Joiner of the United States in 1935, led to a cupwheel design with a nearly linear response and an error of less than 3% up to 60 mi/h. Patterson found that each cup produced maximum torque when it was at 45° to the wind flow. The three-cup anemometer also had a more constant torque and responded more quickly to gusts than the four-cup anemometer. #### Three cup wind direction {#three_cup_wind_direction} The three-cup anemometer was further modified by Australian Dr. Derek Weston in 1991 to also measure wind direction. He added a tag to one cup, causing the cupwheel speed to increase and decrease as the tag moved alternately with and against the wind. Wind direction is calculated from these cyclical changes in speed, while wind speed is determined from the average cupwheel speed. Three-cup anemometers are currently the industry standard for wind resource assessment studies and practice. ### Vane anemometers {#vane_anemometers} One of the other forms of mechanical velocity anemometer is the vane anemometer. It may be described as a windmill or a propeller anemometer. Unlike the Robinson anemometer, whose axis of rotation is vertical, the vane anemometer must have its axis parallel to the direction of the wind and is therefore horizontal. Furthermore, since the wind varies in direction and the axis has to follow its changes, a wind vane or some other contrivance to fulfill the same purpose must be employed. A vane anemometer thus combines a propeller and a tail on the same axis to obtain accurate and precise wind speed and direction measurements from the same instrument. The speed of the fan is measured by a revolution counter and converted to a windspeed by an electronic chip. Hence, volumetric flow rate may be calculated if the cross-sectional area is known. In cases where the direction of the air motion is always the same, as in ventilating shafts of mines and buildings, wind vanes known as air meters are employed, and give satisfactory results. <File:Wind> speed and direction instrument - NOAA.jpg\\|Vane style of anemometer <File:Prop> vane anemometer.jpg\\|Helicoid propeller anemometer incorporating a wind vane for orientation <File:Anemometer-IMG> 4734-white.jpg\\|Hand-held low-speed vane anemometer <File:Digital_Handheld_Anemometer.jpg%7CHand-held> digital anemometer or Byram anenometer. ### Hot-wire anemometers {#hot_wire_anemometers} Hot wire anemometers use a fine wire (on the order of several micrometres) electrically heated to some temperature above the ambient. Air flowing past the wire cools the wire. As the electrical resistance of most metals is dependent upon the temperature of the metal (tungsten is a popular choice for hot-wires), a relationship can be obtained between the resistance of the wire and the speed of the air. In most cases, they cannot be used to measure the direction of the airflow, unless coupled with a wind vane. Several ways of implementing this exist, and hot-wire devices can be further classified as CCA (constant current anemometer), CVA (constant voltage anemometer) and CTA (constant-temperature anemometer). The voltage output from these anemometers is thus the result of some sort of circuit within the device trying to maintain the specific variable (current, voltage or temperature) constant, following Ohm\'s law. Additionally, PWM (pulse-width modulation) anemometers are also used, wherein the velocity is inferred by the time length of a repeating pulse of current that brings the wire up to a specified resistance and then stops until a threshold \"floor\" is reached, at which time the pulse is sent again. Hot-wire anemometers, while extremely delicate, have extremely high frequency-response and fine spatial resolution compared to other measurement methods, and as such are almost universally employed for the detailed study of turbulent flows, or any flow in which rapid velocity fluctuations are of interest. An industrial version of the fine-wire anemometer is the thermal flow meter, which follows the same concept, but uses two pins or strings to monitor the variation in temperature. The strings contain fine wires, but encasing the wires makes them much more durable and capable of accurately measuring air, gas, and emissions flow in pipes, ducts, and stacks. Industrial applications often contain dirt that will damage the classic hot-wire anemometer. ### Laser Doppler anemometers {#laser_doppler_anemometers} In laser Doppler velocimetry, laser Doppler anemometers use a beam of light from a laser that is divided into two beams, with one propagated out of the anemometer. Particulates (or deliberately introduced seed material) flowing along with air molecules near where the beam exits reflect, or backscatter, the light back into a detector, where it is measured relative to the original laser beam. When the particles are in great motion, they produce a Doppler shift for measuring wind speed in the laser light, which is used to calculate the speed of the particles, and therefore the air around the anemometer. ### Ultrasonic anemometers {#ultrasonic_anemometers} Ultrasonic anemometers, first developed in the 1950s, use ultrasonic sound waves to measure wind velocity. They measure wind speed based on the time of flight of sonic pulses between pairs of transducers. The time that a sonic pulse takes to travel from one transducer to its pair is inversely proportionate to the speed of sound in air plus the wind velocity in the same direction: $t=\frac{L}{(c+v)}$ where $t$ is the time of flight, $L$ is the distance between transducers, $c$ is the speed of sound in air and $v$ is the wind velocity. In other words, the faster the wind is blowing, the faster the sound pulse travels. To correct for the speed of sound in air (which varies according to temperature, pressure and humidity) sound pulses are sent in both directions and the wind velocity is calculated using the forward and reverse times of flight: $v=\frac{1}{2} L(\frac{1}{t_1}-\frac{1}{t_2})$ where $t_1$ is the forward time of flight and $t_2$ the reverse. Because ultrasonic anenometers have no moving parts, they need little maintenance and can be used in harsh environments. They operate over a wide range of wind speeds. They can measure rapid changes in wind speed and direction, taking many measurements each second, and so are useful in measuring turbulent air flow patterns. Their main disadvantage is the distortion of the air flow by the structure supporting the transducers, which requires a correction based upon wind tunnel measurements to minimize the effect. Rain drops or ice on the transducers can also cause inaccuracies. Since the speed of sound varies with temperature, and is virtually stable with pressure change, ultrasonic anemometers are also used as thermometers. Measurements from pairs of transducers can be combined to yield a measurement of velocity in 1-, 2-, or 3-dimensional flow. Two-dimensional (wind speed and wind direction) sonic anemometers are used in applications such as weather stations, ship navigation, aviation, weather buoys and wind turbines. Monitoring wind turbines usually requires a refresh rate of wind speed measurements of 3 Hz, easily achieved by sonic anemometers. Three-dimensional sonic anemometers are widely used to measure gas emissions and ecosystem fluxes using the eddy covariance method when used with fast-response infrared gas analyzers or laser-based analyzers. #### Acoustic resonance anemometers {#acoustic_resonance_anemometers} Acoustic resonance anemometers are a more recent variant of sonic anemometer. The technology was invented by Savvas Kapartis and patented in 1999. Whereas conventional sonic anemometers rely on time of flight measurement, acoustic resonance sensors use resonating acoustic (ultrasonic) waves within a small purpose-built cavity in order to perform their measurement. Built into the cavity is an array of ultrasonic transducers, which are used to create the separate standing-wave patterns at ultrasonic frequencies. As wind passes through the cavity, a change in the wave\'s property occurs (phase shift). By measuring the amount of phase shift in the received signals by each transducer, and then by mathematically processing the data, the sensor is able to provide an accurate horizontal measurement of wind speed and direction. Because acoustic resonance technology enables measurement within a small cavity, the sensors tend to be typically smaller in size than other ultrasonic sensors. The small size of acoustic resonance anemometers makes them physically strong and easy to heat, and therefore resistant to icing. This combination of features means that they achieve high levels of data availability and are well suited to wind turbine control and to other uses that require small robust sensors such as battlefield meteorology. One issue with this sensor type is measurement accuracy when compared to a calibrated mechanical sensor. For many end uses, this weakness is compensated for by the sensor\'s longevity and the fact that it does not require recalibration once installed. ## Pressure anemometers {#pressure_anemometers} The first designs of anemometers that measure the pressure were divided into plate and tube classes. ### Plate anemometers {#plate_anemometers} These are the first modern anemometers. They consist of a flat plate suspended from the top so that the wind deflects the plate. In 1450, the Italian art architect Leon Battista Alberti invented the first such mechanical anemometer; in 1663 it was re-invented by Robert Hooke. Later versions of this form consisted of a flat plate, either square or circular, which is kept normal to the wind by a wind vane. The pressure of the wind on its face is balanced by a spring. The compression of the spring determines the actual force which the wind is exerting on the plate, and this is either read off on a suitable gauge, or on a recorder. Instruments of this kind do not respond to light winds, are inaccurate for high wind readings, and are slow at responding to variable winds. Plate anemometers have been used to trigger high wind alarms on bridges. ### Tube anemometers {#tube_anemometers} James Lind\'s anemometer of 1775 consisted of a vertically mounted glass U tube containing a liquid manometer (pressure gauge), with one end bent out in a horizontal direction to face the wind flow and the other vertical end capped. Though the Lind was not the first, it was the most practical and best known anemometer of this type. If the wind blows into the mouth of a tube, it causes an increase of pressure on one side of the manometer. The wind over the open end of a vertical tube causes little change in pressure on the other side of the manometer. The resulting elevation difference in the two legs of the U tube is an indication of the wind speed. However, an accurate measurement requires that the wind speed be directly into the open end of the tube; small departures from the true direction of the wind causes large variations in the reading. The successful metal pressure tube anemometer of William Henry Dines in 1892 utilized the same pressure difference between the open mouth of a straight tube facing the wind and a ring of small holes in a vertical tube which is closed at the upper end. Both are mounted at the same height. The pressure differences on which the action depends are very small, and special means are required to register them. The recorder consists of a float in a sealed chamber partially filled with water. The pipe from the straight tube is connected to the top of the sealed chamber and the pipe from the small tubes is directed into the bottom inside the float. Since the pressure difference determines the vertical position of the float this is a measure of the wind speed. The great advantage of the tube anemometer lies in the fact that the exposed part can be mounted on a high pole, and requires no oiling or attention for years; and the registering part can be placed in any convenient position. Two connecting tubes are required. It might appear at first sight as though one connection would serve, but the differences in pressure on which these instruments depend are so minute, that the pressure of the air in the room where the recording part is placed has to be considered. Thus, if the instrument depends on the pressure or suction effect alone, and this pressure or suction is measured against the air pressure in an ordinary room in which the doors and windows are carefully closed and a newspaper is then burnt up the chimney, an effect may be produced equal to a wind of 10 mi/h (16 km/h); and the opening of a window in rough weather, or the opening of a door, may entirely alter the registration. While the Dines anemometer had an error of only 1% at 10 mi/h, it did not respond very well to low winds due to the poor response of the flat plate vane required to turn the head into the wind. In 1918 an aerodynamic vane with eight times the torque of the flat plate overcame this problem. #### Pitot tube static anemometers {#pitot_tube_static_anemometers} Modern tube anemometers use the same principle as in the Dines anemometer, but using a different design. The implementation uses a pitot-static tube, which is a pitot tube with two ports, pitot and static, that is normally used in measuring the airspeed of aircraft. The pitot port measures the dynamic pressure of the open mouth of a tube with pointed head facing the wind, and the static port measures the static pressure from small holes along the side on that tube. The pitot tube is connected to a tail so that it always makes the tube\'s head face the wind. Additionally, the tube is heated to prevent rime ice formation on the tube. There are two lines from the tube down to the devices to measure the difference in pressure of the two lines. The measurement devices can be manometers, pressure transducers, or analog chart recorders. ### Ping-pong ball anemometers {#ping_pong_ball_anemometers} A common anemometer for basic use is constructed from a ping-pong ball attached to a string. When the wind blows horizontally, it presses on and moves the ball; because ping-pong balls are very lightweight, they move easily in light winds. Measuring the angle between the string-ball apparatus and the vertical gives an estimate of the wind speed. This type of anemometer is mostly used for middle-school level instruction, which most students make on their own, but a similar device was also flown on the Phoenix Mars Lander. ### Effect of density on measurements {#effect_of_density_on_measurements} In the tube anemometer the dynamic pressure is actually being measured, although the scale is usually graduated as a velocity scale. If the actual air density differs from the calibration value, due to differing temperature, elevation or barometric pressure, a correction is required to obtain the actual wind speed. Approximately 1.5% (1.6% above 6,000 feet) should be added to the velocity recorded by a tube anemometer for each 1000 ft (5% for each kilometer) above sea-level. ## Effect of icing {#effect_of_icing} At airports, it is essential to have accurate wind data under all conditions, including freezing precipitation. Anemometry is also required in monitoring and controlling the operation of wind turbines, which in cold environments are prone to in-cloud icing. Icing alters the aerodynamics of an anemometer and may entirely block it from operating. Therefore, anemometers used in these applications must be internally heated. Both cup anemometers and sonic anemometers are presently available with heated versions. ## Instrument location {#instrument_location} In order for wind speeds to be comparable from location to location, the effect of the terrain needs to be considered, especially in regard to height. Other considerations are the presence of trees, and both natural canyons and artificial canyons (urban buildings). The standard anemometer height in open rural terrain is 10 meters.	2025-06-20T00:00:00
3,010	Alan Jay Lerner	Alan Jay Lerner (August 31, 1918 -- June 14, 1986) was an American lyricist and librettist. In collaboration with Frederick Loewe, and later Burton Lane, he created some of the world\'s most popular and enduring works of musical theatre both for the stage and on film. Lerner won three Tony Awards and three Academy Awards, among other honors. ## Early life and education {#early_life_and_education} Lerner was born in New York City to a Jewish family. He was the son of Edith (`{{née}}`{=mediawiki} Adelson) and Joseph Jay Lerner, whose brother, Samuel Alexander Lerner, was founder and owner of the Lerner Stores, a chain of dress shops. One of Lerner\'s cousins was the radio comedian and television game show panelist Henry Morgan. Lerner was educated at Bedales School in England, The Choate School (now Choate Rosemary Hall) in Wallingford, Connecticut, (where he wrote \"The Choate Marching Song\") and Harvard. He attended both Camp Androscoggin and Camp Greylock. At both Choate and Harvard, Lerner was a classmate of John F. Kennedy; at Choate they had worked together on the yearbook staff. Like Cole Porter at Yale and Richard Rodgers at Columbia, his career in musical theater began with his collegiate contributions, in Lerner\'s case to the annual Harvard Hasty Pudding musicals. During the summers of 1936 and 1937, Lerner studied music composition at Juilliard. While attending Harvard, he lost his sight in his left eye due to an accident in the boxing ring. In 1957, Lerner and Leonard Bernstein, another of Lerner\'s college classmates, collaborated on \"Lonely Men of Harvard\", a tongue-in-cheek salute to their alma mater. ## Career Owing to his eye injury, Lerner could not serve in World War II. Instead he wrote radio scripts, including Your Hit Parade, until he was introduced to German-Austrian composer Frederick Loewe, who needed a partner, in 1942 at the Lamb\'s Club. While at the Lamb\'s, he also met Lorenz Hart, with whom he would also collaborate. Lerner and Loewe\'s first collaboration was a musical adaptation of Barry Conners\'s farce The Patsy called Life of the Party for a Detroit stock company. The lyrics were mostly written by Earle Crooker, but he had left the project, with the score needing vast improvement. It enjoyed a nine-week run and encouraged the duo to join forces with Arthur Pierson for What\'s Up?, which opened on Broadway in 1943. It ran for 63 performances and was followed two years later by The Day Before Spring. Their first hit was Brigadoon (1947), a romantic fantasy set in a mystical Scottish village, directed by Robert Lewis. It was followed in 1951 by the Gold Rush story Paint Your Wagon. While the show ran for nearly a year and included songs that later became pop standards, such as \"They Call the Wind Maria\", it was less successful than Lerner\'s previous work. He later said of Paint Your Wagon, it was \"a success but not a hit.\" Lerner worked with Kurt Weill on the stage musical Love Life (1948) and Burton Lane on the movie musical Royal Wedding (1951). In that same year Lerner also wrote the Oscar-winning original screenplay for An American in Paris, produced by Arthur Freed and directed by Vincente Minnelli. This was the same team who would later join with Lerner and Loewe to create Gigi. In 1956, Lerner and Loewe unveiled My Fair Lady. By this time, too, Lerner and Burton Lane were already working on a musical about Li\'l Abner. Gabriel Pascal owned the rights to Pygmalion, which had been unsuccessful with other composers who tried to adapt it into a musical. Arthur Schwartz and Howard Dietz first tried, and then Richard Rodgers and Oscar Hammerstein II attempted, but gave up and Hammerstein told Lerner, \"Pygmalion had no subplot\". Lerner and Loewe\'s adaptation of George Bernard Shaw\'s Pygmalion retained his social commentary and added appropriate songs for the characters of Henry Higgins and Eliza Doolittle, played originally by Rex Harrison and Julie Andrews. It set box-office records in New York and London. When brought to the screen in 1964, the movie version won eight Oscars, including Best Picture and Best Actor for Rex Harrison. Lerner and Loewe\'s run of success continued with their next project, a film adaptation of stories from Colette, the Academy Award-winning film musical Gigi, starring Leslie Caron, Louis Jourdan and Maurice Chevalier. The film won all of its nine Oscar nominations, a record at that time, and a special Oscar for co-star Maurice Chevalier. The Lerner-Loewe partnership cracked under the stress of producing the Arthurian Camelot in 1960, with Loewe resisting Lerner\'s desire to direct as well as write when original director Moss Hart suffered a heart attack in the last few months of rehearsals and died about a year after the show\'s Broadway premiere. Lerner was hospitalized with bleeding ulcers while Loewe continued to have heart troubles. Camelot was a hit nonetheless, and immediately following the assassination of John F. Kennedy, his widow told reporter Theodore H. White that JFK\'s administration reminded her of the \"one brief shining moment\" of Lerner and Loewe\'s Camelot. As of the early 21st century, Camelot was still invoked to describe the idealism, romance, and tragedy of the Kennedy years. Loewe retired to Palm Springs, California, while Lerner went through a series of musicals---some successful, some not---with such composers as André Previn (Coco), John Barry (Lolita, My Love), Leonard Bernstein (1600 Pennsylvania Avenue), Burton Lane (Carmelina) and Charles Strouse (Dance a Little Closer, based on the film, Idiot\'s Delight, nicknamed Close A Little Faster by Broadway humorists because it closed on opening night). Most biographers`{{who\|date=July 2015}}`{=mediawiki} blame Lerner\'s professional decline on the lack of a strong director with whom Lerner could collaborate, as Neil Simon did with Mike Nichols or Stephen Sondheim with Harold Prince. (Moss Hart, who had directed My Fair Lady, died shortly after Camelot opened.) In 1965 Lerner collaborated again with Burton Lane on the musical On a Clear Day You Can See Forever, which was adapted for film in 1970. At this time, Lerner was hired by film producer Arthur P. Jacobs to write a treatment for an upcoming film project, Doctor Dolittle, but Lerner abrogated his contract after several non-productive months of non-communicative procrastination and was replaced with Leslie Bricusse. Lerner was inducted into the Songwriters Hall of Fame in 1971. In 1973, Lerner coaxed Loewe out of retirement to augment the Gigi score for a musical stage adaptation. The following year they collaborated on a musical film version of The Little Prince, based on the classic children\'s tale by Antoine de Saint-Exupéry. This film was a critical and box office failure, but it has gained a modern following. Lerner\'s autobiography, The Street Where I Live (1978), was an account of three of his and Loewe\'s successful collaborations, My Fair Lady, Gigi, and Camelot, along with personal information. In the last year of his life, he published The Musical Theatre: A Celebration, a well-reviewed history of the theatre, with personal anecdotes and humor. The Los Angeles Times reviewer wrote: \"There are several reasons why this book makes a fine introduction to musical theater. One is that Lerner knows exactly what was new, and when and why\....In \"The Musical Theatre,\" one is privy to the judgment of a man\... who expresses his opinions in a forthright, warm and personal manner.\" A book of Lerner\'s lyrics entitled A Hymn To Him, edited by a British writer Benny Green, was published in 1987. At the time of Lerner\'s death, he had been working with Gerard Kenny and Kristi Kane in London on a musical version of the film My Man Godfrey. He had also received an urgent call from Andrew Lloyd Webber, asking him to write the lyrics to The Phantom of the Opera. He wrote \"Masquerade\", but he then informed Webber that he wanted to leave the project because he was losing his memory (he had developed metastatic lung cancer) and Charles Hart replaced him. He had turned down an invitation to write the English-language lyrics for the musical version of Les Misérables. After Lerner\'s death, Paul Blake made a musical revue based on Lerner\'s lyrics and life entitled Almost Like Being In Love, which featured music by Loewe, Lane, Previn, Strouse, and Weill. The show ran for 10 days at the Herbst Theatre in San Francisco. ## Songwriting Lerner often struggled with writing his lyrics. He was uncharacteristically able to complete \"I Could Have Danced All Night\" from My Fair Lady in one 24-hour period. He usually spent months on each song and was constantly rewriting them. Lerner was said`{{by whom\|date=August 2017}}`{=mediawiki} to have insecurity about his talent. He would sometimes write songs with someone in mind. For instance, he changed the rhymes in some lines of \"I\'ve Grown Accustomed To Her Face\" to ones that Rex Harrison was more comfortable with. Lerner said of writing: `{{Blockquote\|You have to keep in mind that there is no such thing as realism or naturalism in the theater. That is a myth. If there was realism in the theater, there would never be a third act. Nothing ends that way. A man's life is made up of thousands and thousands of little pieces. In writing fiction, you select 20 or 30 of them. In a musical, you select even fewer than that.}}`{=mediawiki} `{{Blockquote\| First, we decide where a song is needed in a play. Second, what is it going to be about? Third, we discuss the mood of the song. Fourth, I give (Loewe) a title. Then he writes the music to the title and the general feeling of the song is established. After he's written the melody, then I write the lyrics.}}`{=mediawiki} In a 1979 interview on NPR\'s All Things Considered, Lerner went into some depth about his lyrics for My Fair Lady. Professor Henry Higgins sings, \"Look at her, a prisoner of the gutters / Condemned by every syllable she utters / By right she should be taken out and hung / For the cold-blooded murder of the English tongue.\" Lerner said he knew the lyric used incorrect grammar for the sake of a rhyme. He was later approached about it by another lyricist: `{{Blockquote\|I thought, oh well, maybe nobody will notice it, but not at all. Two nights after it opened, I ran into [[Noël Coward]] in a restaurant, and he walked over and he said, "Dear boy, it is ''hanged'', not ''hung''." I said, "Oh, Noel, I know it, I know it! You know, shut up!" So, and there's another, "Than to ever let a woman in my life." It should be, "as to ever let a woman in my life," but it just didn't sing well. }}`{=mediawiki} ## Dramatists Guild {#dramatists_guild} Alan Jay Lerner was an advocate for writers\' rights in theatre. He was a member of the Dramatists Guild of America. In 1960, he was elected as the twelfth president of the non-profit organization. He continued to serve as the Guild\'s president until 1964. ## Personal life {#personal_life} For nearly twenty years, Lerner was addicted to amphetamines; during the 1960s he was a patient of Max Jacobson, known as \"Dr. Feelgood\", who administered injections of \"vitamins with enzymes\" that were in fact laced with amphetamines. Lerner\'s addiction is believed to have been the result of Jacobson\'s practice. ### Marriages and children {#marriages_and_children} Lerner married eight times: Ruth Boyd (1940--1947), singer Marion Bell (1947--1949), actress Nancy Olson (1950--1957), lawyer Micheline Muselli Pozzo di Borgo (1957--1965), editor Karen Gundersen (1966--1974), Sandra Payne (1974--1976), Nina Bushkin (1977--1981) and Liz Robertson (1981--1986 \[his death\]). Four of his eight wives --- Olson, Payne, Bushkin, and Robertson --- were actresses. His seventh wife, Nina Bushkin, whom he married on May 30, 1977, was the director of development at Mannes College of Music and the daughter of composer and musician Joey Bushkin. After their divorce in 1981, Lerner was ordered to pay her a settlement of \$50,000. Lerner wrote in his autobiography (as quoted by The New York Times): \"All I can say is that if I had no flair for marriage, I also had no flair for bachelorhood.\" All of this lent some irony to the lyrics for his song Get Me to the Church on Time. Lerner had four children --- three daughters, Susan (by Boyd), Liza, and Jennifer (by Olson), and one son, screenwriter and journalist Michael Alan Lerner (by di Borgo). Lerner\'s multiple divorces cost him much of his wealth. Still, he was primarily responsible for his financial ups and downs and was less than truthful about his financial fecklessness. It was claimed that his divorce settlement from Micheline Muselli Pozzo di Borgo (his fourth wife) cost him an estimated \$1 million in 1965. This was untrue. Lerner\'s pattern of financial mismanagement continued until his death from cancer in 1986 when he reportedly owed the U.S. Internal Revenue Service over US\$1 million `{{USDCY\|1e6\|1986}}`{=mediawiki} in back taxes and was unable to pay for his final medical expenses. ## Death On June 14, 1986, Lerner died of lung cancer in Manhattan at the age of 67. At the time of his death he was married to actress Liz Robertson, who was 36 years his junior. He lived in Center Island, New York. He has a memorial plaque in St Paul\'s Church, the Actors\' Church in Covent Garden in London. ## Awards and honors {#awards_and_honors} - American Theater Hall of Fame 1979 - Kennedy Center Honors 1985 Academy Award - Best Original Screenplay, 1951 An American in Paris - Best Adapted Screenplay, 1958 Gigi - Best Original Song, 1958 Gigi Golden Globes - Best Original Song, 1968 Camelot - Best Original Score, 1975 The Little Prince Tony Award - Best Book of a Musical, 1957 My Fair Lady - Best Original Score, 1957 My Fair Lady and 1974 Gigi New York Drama Critics Circle - Best Musical, 1947 Brigadoon - Best Musical, 1956 My Fair Lady Johnny Mercer Award - Lyric Writing, 1985, Lifetime ## Works ### Stage - Life of the Party (1942), with Frederick Loewe - What\'s Up? (1943), with Frederick Loewe - The Day Before Spring (1945), with Frederick Loewe - Brigadoon (1947), with Frederick Loewe - Love Life (1948), with Kurt Weill - Paint Your Wagon (1951), Frederick Loewe - My Fair Lady (1956), with Frederick Loewe - Camelot (1960), with Frederick Loewe - On a Clear Day You Can See Forever (1965), with Burton Lane - Coco (1969), with André Previn - Lolita, My Love (1971), with John Barry - Gigi (1973), based on the 1958 film of the same name, with Frederick Loewe - 1600 Pennsylvania Avenue (1976), with Leonard Bernstein - Carmelina (1979), with Burton Lane and Joseph Stein - Dance a Little Closer (1983), with Charles Strouse - My Man Godfrey (1984), unfinished, with Gerard Kenny ### Films Source: TCM - Royal Wedding, 1951 (screenwriter/lyricist) - An American in Paris (1951) (writer) - Brigadoon, 1954 (film) (screenwriter/lyricist) - Gigi, 1958 (screenwriter/lyricist) - The Adventures of Huckleberry Finn, 1960 (lyricist) - My Fair Lady, 1964 (screenwriter/lyricist) - Camelot, 1967 (screenwriter/lyricist) - Paint Your Wagon, 1969 (producer/screenwriter/lyricist) - On a Clear Day You Can See Forever, 1970 (screenwriter/lyricist) - The Little Prince, 1974 (screenwriter/lyricist) - Tribute, 1980 (\"It\'s All for the Best\", lyricist) - Secret Places, 1984 (title song lyricist)	2025-06-20T00:00:00
3,012	Al Capp	Alfred Gerald Caplin (September 28, 1909 -- November 5, 1979), better known as Al Capp, was an American cartoonist and humorist best known for the satirical comic strip Li\'l Abner, which he created in 1934 and continued writing and (with help from assistants) drawing until 1977. He also wrote the comic strips Abbie an\' Slats (in the years 1937--45) and Long Sam (1954). He won the National Cartoonists Society\'s Reuben Award in 1947 for Cartoonist of the Year, and their 1979 Elzie Segar Award, posthumously for his \"unique and outstanding contribution to the profession of cartooning\". Capp\'s comic strips dealt with urban experiences in the Northern United States until the year he introduced \"Li\'l Abner\". Although Capp was from Connecticut, he spent 43 years writing about the fictional Southern town of Dogpatch, reaching an estimated 60 million readers in more than 900 American newspapers and 100 more papers in 28 countries internationally. M. Thomas Inge says Capp made a large personal fortune through the strip and \"had a profound influence on the way the world viewed the American South\". ## Early life and education {#early_life_and_education} Capp was born in New Haven, Connecticut, of East European Jewish heritage. He was the eldest child of Otto Philip Caplin (1885--1964) and Matilda (Davidson) Caplin (1884--1948). Otto Caplin was a failed businessman and an amateur cartoonist; Al\'s brothers Elliot and Jerome were also cartoonists, and his sister Madeline was a publicist. Capp\'s parents were both natives of Latvia whose families had migrated to New Haven in the 1880s. \"My mother and father had been brought to this country from Russia when they were infants\", wrote Capp in 1978. \"Their fathers had found that the great promise of America was true --- it was no crime to be a Jew.\" The Caplins were indigent; Capp recalled stories of his mother going out in the night to sift through ash barrels for reusable bits of coal. In August 1919, at age nine, Capp was run over by a trolley car and had his left leg amputated above the knee. According to his father Otto\'s unpublished autobiography, young Capp was not prepared for the amputation beforehand; having been in a coma for days, he suddenly awoke to discover that his leg had been removed. He was eventually given a prosthetic leg but only learned to use it by adopting a slow way of walking which became increasingly painful as he aged. The childhood tragedy of losing a leg likely helped shape Capp\'s cynical worldview, which was darker and more sardonic than that of most newspaper cartoonists. \"I was indignant as hell about that leg,\" he revealed in a November 1950 interview in Time magazine. \"The secret of how to live without resentment or embarrassment in a world in which I was different from everyone else\", Capp philosophically wrote, \"was to be indifferent to that difference.\" The prevailing opinion among his friends was that Capp\'s Swiftian satire was, to some degree, a creatively channeled, compensatory response to his disability. Capp\'s father introduced him to drawing as a form of therapy. He became quite proficient, advancing mostly on his own. Among his earliest influences were Punch cartoonist--illustrator Phil May and American comic strip cartoonists Tad Dorgan, Cliff Sterrett, Rube Goldberg, Rudolph Dirks, Fred Opper, Billy DeBeck, George McManus, and Milt Gross. At about this same time, Capp became a voracious reader. According to Capp\'s brother Elliot, Alfred had finished all of Shakespeare and George Bernard Shaw before he was 13 years old. Among his childhood favorites were Dickens, Smollett, Mark Twain, Booth Tarkington, and later, Robert Benchley and S. J. Perelman. Capp spent five years at Bridgeport High School in Bridgeport, Connecticut, without receiving a diploma. He liked to joke about how he failed geometry for nine straight terms. His formal training came from a series of art schools in the Northeast. Attending three of them in rapid succession, the impoverished Capp was thrown out of each for nonpayment of tuition---the Boston Museum School of Fine Arts, the Pennsylvania Academy of the Fine Arts, and Designers Art School in Boston---the last before launching his career. Capp already had decided to become a cartoonist. \"I heard that Bud Fisher (creator of Mutt and Jeff) got \$3,000 a week and was constantly marrying French countesses\", Capp said. \"I decided that was for me.\" In early 1932, Capp hitchhiked to New York City. He lived in \"airless rat holes\" in Greenwich Village and turned out advertising strips at \$2 each while scouring the city hunting for jobs. He eventually found work at the Associated Press when he was 23 years old. By March 1932, Capp was drawing Colonel Gilfeather, a single-panel, AP-owned property created in 1930 by Dick Dorgan. Capp changed the focus and title to Mister Gilfeather but soon grew to hate the feature. He left the Associated Press in September 1932. Before leaving, he met Milton Caniff and the two became lifelong friends. Capp moved to Boston and married Catherine Wingate Cameron, whom he had met earlier in art class. She died in 2006 at the age of 96. Leaving his new wife with her parents in Amesbury, Massachusetts, he subsequently returned to New York in 1933, in the midst of the Great Depression. \"I was 23, I carried a mass of drawings, and I had nearly five dollars in my pocket. People were sleeping in alleys then, willing to work at anything.\" There he met Ham Fisher, who hired him to ghost on Joe Palooka. During one of Fisher\'s extended vacations, Capp\'s Joe Palooka story arc introduced a stupid, coarse, oafish mountaineer named \"Big Leviticus\", a crude prototype. (Leviticus was much closer to Capp\'s later villains Lem and Luke Scragg than to the much more appealing and innocent Li\'l Abner.) Also during this period, Capp was working at night on samples for the strip that eventually became Li\'l Abner. He based his cast of characters on the authentic mountain-dwellers he met `{{citation needed span\|text=while hitchhiking through rural [[West Virginia]] and the [[Cumberland Valley]] as a teenager.\|reason=This activity needs to be substantiated, not just claimed. When did he do it (and why)? He spent five years just in high school in Bridgeport, Connecticut, as a teen, then attended three art schools in the Northeast shortly afterwards. In 1932, he hitchikes from Massachusetts to New York City (as 23). A reliable citation is required.\|date=January 2025}}`{=mediawiki} (This would have been before the Tennessee Valley Authority Act of 1933 began the years-long process of bringing basic utilities like electricity and running water to the region.) Leaving Joe Palooka, Capp sold Li\'l Abner to United Feature Syndicate (later known as United Media). The feature was launched on Monday, August 13, 1934, in eight North American newspapers---including the New York Mirror---and was an immediate success. Alfred G. Caplin eventually became \"Al Capp\" because the syndicate felt the original would not fit in a cartoon frame. Capp had his name changed legally in 1949. His younger brother, Elliot Caplin, also became a comic strip writer, best known for co-creating the soap opera strip The Heart of Juliet Jones with artist Stan Drake and conceiving the comic strip character Broom-Hilda with cartoonist Russell Myers. Elliot authored several off-Broadway plays, including A Nickel for Picasso (1981), which was based on and dedicated to his mother and his famous brother. ## Li\'l Abner {#lil_abner} What began as a hillbilly burlesque soon evolved into one of the most imaginative, popular, and well-drawn strips of the twentieth century. Featuring vividly outlandish characters, bizarre situations, and equal parts suspense, slapstick, irony, satire, black humor, and biting social commentary, Li\'l Abner is considered a classic of the genre. The comic strip stars Li\'l Abner Yokum---the simple-minded, loutish but good-natured, and eternally innocent hayseed who lives with his parents---scrawny but superhuman Mammy Yokum, and shiftless, childlike Pappy Yokum. \"Yokum\" was a combination of yokel and hokum, although Capp established a deeper meaning for the name during a series of visits around 1965--1970 with comics historians George E. Turner and Michael H. Price: `{{Blockquote\|It's phonetic [[Hebrew language\|Hebrew]]—that's what it is, all right—and that's what I was getting at with the name Yokum, more so than any attempt to sound ''hickish''. That was a fortunate coincidence, of course, that the name should pack a backwoods connotation. But it's a godly conceit, really, playing off a godly name—''[[Joachim]]'' means 'God's determination', something like that—that also happens to have a rustic ring to it.<ref>{{Cite web\|url=https://www.comicmix.com/2007/11/11/li-l-abner-lost-in-hollywood-shuffle-by-michael-h-price/\|title=Li'l Abner Lost in Hollywood, by Michael H. Price\|date=November 11, 2007\|website=ComicMix\|access-date=2020-10-29}}</ref>}}`{=mediawiki} The Yokums live in the backwater hamlet of Dogpatch, Kentucky. Described by its creator as \"an average stone-age community\", Dogpatch mostly consists of hopelessly ramshackle log cabins, pine trees, \"tarnip\" fields, and \"hawg\" wallows. Whatever energy Abner had went into evading the marital goals of Daisy Mae Scragg, his sexy, well-endowed, but virtuous girlfriend, until Capp finally gave in to reader pressure and allowed the couple to marry. This newsworthy event made the cover of Life on March 31, 1952. Capp peopled his comic strip with an assortment of memorable characters, including Marryin\' Sam, Hairless Joe, Lonesome Polecat, Evil-Eye Fleegle, General Bullmoose, Lena the Hyena, Senator Jack S. Phogbound (Capp\'s caricature of the anti-New Deal Dixiecrats), the (shudder!) Scraggs, Available Jones, Nightmare Alice, Earthquake McGoon, and a host of others. Especially notable, certainly from a G.I. point of view, are the beautiful, full-figured women --- Daisy Mae, Wolf Gal, Stupefyin\' Jones, and Moonbeam McSwine (a caricature of his wife Catherine, aside from the dirt) --- all of whom found their way onto the nose art of bomber planes during World War II and the Korean War. Perhaps Capp\'s most popular creations were the Shmoos, creatures whose incredible usefulness and generous nature made them a threat to civilization as we know it. Another famous character was Joe Btfsplk, who wants to be a loving friend but is \"the world\'s worst jinx\", bringing bad luck to all those nearby. Btfsplk (his name is \"pronounced\" by simply blowing a \"raspberry\" or Bronx cheer) always has an iconic dark cloud over his head. Dogpatch residents regularly combat the likes of city slickers, business tycoons, government officials, and intellectuals with their homespun simplicity. Situations often take the characters to other destinations, including New York City, Washington, D.C., Hollywood, tropical islands, the moon, Mars, and some purely fanciful worlds of Capp\'s invention, including El Passionato, Kigmyland, The Republic of Crumbumbo, Skunk Hollow, The Valley of the Shmoon, Planets Pincus Number 2 and 7, and a miserable frozen wasteland known as Lower Slobbovia, a pointedly political satire of backward nations and foreign diplomacy that remains a contemporary reference. According to cultural historian Anthony Harkins: `{{blockquote\|Indeed, ''Li'l Abner'' incorporates such a panoply of characters and ideas that it defies summary. Yet though Capp's storylines often wandered far afield, his hillbilly setting remained a central touchstone, serving both as a microcosm and a distorting carnival mirror of broader American society.<ref>''Hillbilly: A Cultural History of an American Icon'' by Anthony Harkins (2004, Oxford Univ. Press) pp. 124–136</ref>}}`{=mediawiki} The strip\'s popularity grew from an original eight papers to eventually more than 900. At its peak, Li\'l Abner was estimated to have been read daily in the United States by 60 to 70 million people (the U.S. population at the time was only 180 million), with adult readers far outnumbering children. Many communities, high schools, and colleges staged Sadie Hawkins dances patterned after the similar annual event in the strip. Li\'l Abner has one odd design quirk that has puzzled readers for decades: the part in his hair always faces the viewer, no matter which direction Abner is facing. In response to the question \"Which side does Abner part his hair on?\", Capp would answer: \"Both.\" Capp said he finally found the right \"look\" for Li\'l Abner with Henry Fonda\'s character Dave Tolliver in The Trail of the Lonesome Pine (1936). In later years, Capp always claimed to have effectively created the miniskirt, when he first put one on Daisy Mae in the 1930s. ## Parodies, toppers, and alternate strips {#parodies_toppers_and_alternate_strips} Li\'l Abner also features a comic strip-within-the-strip: Fearless Fosdick is a parody of Chester Gould\'s Dick Tracy. It first appeared in 1942, and it proved so popular that it ran intermittently during the next 35 years. Gould was parodied personally in the series as cartoonist \"Lester Gooch\"---the diminutive, much-harassed and occasionally deranged \"creator\" of Fosdick. The style of the Fosdick sequences closely mimicks Tracy, including the urban setting, the outrageous villains, the galloping mortality rate, the crosshatched shadows, and even the lettering style. In 1952, Fosdick was the star of his own short-lived puppet show on NBC, featuring the Mary Chase marionettes. Besides Dick Tracy, Capp parodied many other comic strips in Li\'l Abner---including Steve Canyon, Superman (at least twice; first as \"Jack Jawbreaker\" in 1947, and again in 1966 as \"Chickensouperman\"), Mary Worth as \"Mary Worm\", Peanuts (in 1968, with \"Peewee\", a parody of Charlie Brown, and \"Croopy\", a parody of Snoopy, drawn by \"Bedley Damp\", a parody of Charles Schulz), Rex Morgan, M.D., Little Annie Rooney, and Little Orphan Annie (in which Punjab became \"Punjbag\", an oleaginous slob). Fearless Fosdick---and Capp\'s other spoofs such as \"Little Fanny Gooney\" (1952) and \"Jack Jawbreaker\"---were almost certainly an early inspiration for Harvey Kurtzman\'s Mad Magazine, which began in 1952 as a comic book that specifically parodied other comics in the same distinctive style and subversive manner. Capp also lampooned popular recording idols of the day, including Elvis Presley (\"Hawg McCall\", 1957), Liberace (\"Loverboynik\", 1956), the Beatles (\"the Beasties\", 1964)---and in 1944, Frank Sinatra. \"Sinatra was the first great public figure I ever wrote about,\" Capp once said. \"I called him \'Hal Fascinatra.\' I remember my news syndicate was so worried about what his reaction might be, and we were all surprised when he telephoned and told me how thrilled he was with it. He always made it a point to send me champagne whenever he happened to see me in a restaurant \...\" (from Frank Sinatra, My Father by Nancy Sinatra, 1985). On the other hand, Liberace was \"cut to the quick\" over Loverboynik, according to Capp, and even threatened legal action---as would Joan Baez later, over \"Joanie Phoanie\" in 1967. Capp was just as likely to parody himself; his self-caricature made frequent, tongue-in-cheek appearances in Li\'l Abner. The gag was often at his own expense, as in the above 1951 sequence showing Capp\'s interaction with \"fans\" (see excerpt), or in his 1955 Disneyland parody, \"Hal Yappland\". Just about anything could be a target for Capp\'s satire---in one storyline Li\'l Abner is revealed to be the missing link between ape and man. In another, the search is on in Dogpatch for a pair of missing socks knitted by the first president of the United States. In addition to creating Li\'l Abner, Capp also co-created two other newspaper strips: Abbie an\' Slats with magazine illustrator Raeburn van Buren in 1937, and Long Sam with cartoonist Bob Lubbers in 1954, as well as the Sunday \"topper\" strips Washable Jones, Small Fry (a.k.a. Small Change), and Advice fo\' Chillun. ## Critical recognition {#critical_recognition} According to comics historian Coulton Waugh, a 1947 poll of newspaper readers who claimed they ignored the comics page altogether revealed that many confessed to making a single exception: Li\'l Abner. \"When Li\'l Abner made its debut in 1934, the vast majority of comic strips were designed chiefly to amuse or thrill their readers. Capp turned that world upside-down by routinely injecting politics and social commentary into Li\'l Abner. The strip was the first to regularly introduce characters and story lines having nothing to do with the nominal stars of the strip. The technique---as invigorating as it was unorthodox---was later adopted by cartoonists such as Walt Kelly \[Pogo\] and Garry Trudeau \[Doonesbury\]\", wrote comic strip historian Rick Marschall. According to Marschall, Li\'l Abner gradually evolved into a broad satire of human nature. In his book America\'s Great Comic Strip Artists (1989), Marschall\'s analysis revealed a decidedly misanthropic subtext. Over the years, Li\'l Abner has been adapted to radio, animated cartoons, stage production, motion pictures, and television. Capp has been compared, at various times, to Mark Twain, Dostoevski, Jonathan Swift, Lawrence Sterne, and Rabelais. Fans of the strip ranged from novelist John Steinbeck---who called Capp \"possibly the best writer in the world today\" in 1953 and even earnestly recommended him for the Nobel Prize in literature---to media critic and theorist Marshall McLuhan, who considered Capp \"the only robust satirical force in American life\". John Updike, comparing Abner to a \"hillbilly Candide\", added that the strip\'s \"richness of social and philosophical commentary approached the Voltairean\". Charlie Chaplin, William F. Buckley, Al Hirschfeld, Harpo Marx, Russ Meyer, John Kenneth Galbraith, Ralph Bakshi, Shel Silverstein, Hugh Downs, Gene Shalit, Frank Cho, Daniel Clowes, and (reportedly) even Queen Elizabeth have confessed to being fans of Li\'l Abner. Li\'l Abner was also the subject of the first book-length scholarly assessment of an American comic strip ever published. Li\'l Abner: A Study in American Satire by Arthur Asa Berger (Twayne, 1969) contained serious analyses of Capp\'s narrative technique, his use of dialogue, self-caricature, and grotesquerie, the place of Li\'l Abner in American satire, and the significance of social criticism and the graphic image. \"One of the few strips ever taken seriously by students of American culture,\" wrote Professor Berger, \"Li\'l Abner is worth studying \... because of Capp\'s imagination and artistry, and because of the strip\'s very obvious social relevance.\" It was reprinted by the University Press of Mississippi in 1994. ## The 1940s and 1950s {#the_1940s_and_1950s} During World War II and for many years afterward, Capp worked tirelessly going to hospitals to entertain patients, especially to cheer recent amputees and explain to them that the loss of a limb did not mean an end to a happy and productive life. Making no secret of his own disability, Capp openly joked about his prosthetic leg his whole life. In 1946, Capp created a special full-color comic book, Al Capp by Li\'l Abner, to be distributed by the Red Cross to encourage the thousands of amputee veterans returning from the war. Capp also was involved with the Sister Kenny Foundation, which pioneered new treatments for polio in the 1940s. Serving in his capacity as honorary chairman, Capp made public appearances on its behalf for years, contributed free artwork for its annual fundraising appeals, and entertained disabled and paraplegic children in children\'s hospitals with inspirational pep talks, humorous stories, and sketches. In 1940, an RKO movie adaptation starred Granville Owen (later known as Jeff York) as Li\'l Abner, with Buster Keaton taking the role of Lonesome Polecat, and featuring a title song with lyrics by Milton Berle. A successful musical comedy adaptation of the strip opened on Broadway at the St. James Theater on November 15, 1956, and had a long run of 693 performances, followed by a nationwide tour. The stage musical, with music and lyrics by Gene de Paul and Johnny Mercer, was adapted into a Technicolor motion picture at Paramount in 1959 by producer Norman Panama and director Melvin Frank, with a score by Nelson Riddle. Several performers repeated their Broadway roles in the film, most memorably Julie Newmar as Stupefyin\' Jones and Stubby Kaye as Marryin\' Sam. Other highlights of that decade included the 1942 debut of Fearless Fosdick as Abner\'s \"ideel\" (hero); the 1946 Lena the Hyena Contest, in which a hideous Lower Slobbovian gal was ultimately revealed in the harrowing winning entry (as judged by Frank Sinatra, Boris Karloff, and Salvador Dalí) drawn by noted cartoonist Basil Wolverton; and an ill-fated Sunday parody of Gone With the Wind that aroused anger and legal threats from author Margaret Mitchell, and led to a printed apology within the strip. In October 1947, Li\'l Abner met Rockwell P. Squeezeblood, head of the abusive and corrupt Squeezeblood Comic Strip Syndicate. The resulting sequence, \"Jack Jawbreaker Fights Crime!\", was a devastating satire of Jerry Siegel and Joe Shuster\'s notorious exploitation by DC Comics over Superman. It was later reprinted in The World of Li\'l Abner (1953). (Siegel and Shuster had earlier poked fun at Capp in a Superman story in Action Comics #55, December 1942, in which a cartoonist named \"Al Hatt\" invents a comic strip featuring the hillbilly \"Tiny Rufe\".) In 1947, Capp earned a Newsweek cover story. That same year the New Yorker\'s profile on him was so long that it ran in consecutive issues. In 1948, Capp reached a creative peak with the introduction of the Shmoos, lovable and innocent fantasy creatures who reproduced at amazing speed and brought so many benefits that, ironically, the world economy was endangered. The much-copied storyline was a parable that was metaphorically interpreted in many different ways at the outset of the Cold War. Following his close friend Milton Caniff\'s lead (with Steve Canyon), Capp had recently fought a successful battle with the syndicate to gain complete ownership of his feature when the Shmoos debuted. As a result, he reaped enormous financial rewards from the unexpected (and almost unprecedented) merchandising phenomenon that followed. As in the strip, Shmoos suddenly appeared to be everywhere in 1949 and 1950---including a Time cover story. A paperback collection of the original sequence, The Life and Times of the Shmoo, became a bestseller for Simon & Schuster. Shmoo dolls, clocks, watches, jewelry, earmuffs, wallpaper, fishing lures, air fresheners, soap, ice cream, balloons, ashtrays, comic books, records, sheet music, toys, games, Halloween masks, salt and pepper shakers, decals, pinbacks, tumblers, coin banks, greeting cards, planters, neckties, suspenders, belts, curtains, fountain pens, and other Shmoo paraphernalia were produced. A garment factory in Baltimore turned out a whole line of Shmoo apparel, including \"Shmooveralls\". The original sequence and its 1959 sequel The Return of the Shmoo have been collected in print many times since, most recently in 2011, always to high sales figures. The Shmoos later had their own animated television series. Capp followed this success with other allegorical fantasy critters, including the aboriginal and masochistic \"Kigmies\", who craved abuse (a story that began as a veiled comment on racial and religious oppression), the dreaded \"Nogoodniks\" (or bad shmoos), and the irresistible \"Bald Iggle\", a guileless creature whose sad-eyed countenance compelled involuntary truthfulness---with predictably disastrous results. Li\'l Abner was censored for the first time, but not the last, in September 1947 and was pulled from papers by Scripps-Howard. The controversy, as reported in Time, centered on Capp\'s portrayal of the United States Senate. Edward Leech of Scripps said, \"We don\'t think it is good editing or sound citizenship to picture the Senate as an assemblage of freaks and crooks \... boobs and undesirables.\" Capp criticized Senator Joseph McCarthy in 1954, calling him a \"poet\". \"He uses poetic license to try to create the beautifully ordered world of good guys and bad guys that he wants,\" said Capp. \"He seems at his best when terrifying the helpless and naïve.\" Capp received the National Cartoonists Society\'s Billy DeBeck Memorial Award in 1947 for Cartoonist of the Year. (When the award name was changed in 1954, Capp also retroactively received a Reuben statuette.) He was an outspoken pioneer in favor of diversifying the NCS by admitting women cartoonists. Originally, the Society had disallowed female members. Capp briefly resigned his membership in 1949 to protest their refusal of admission to Hilda Terry, creator of the comic strip Teena. According to Tom Roberts, author of Alex Raymond: His Life and Art (2007), Capp delivered a stirring speech that was instrumental in changing those rules. The NCS finally accepted female members the following year. In December 1952, Capp published an article in Real magazine entitled \"The REAL Powers in America\" that further challenged the conventional attitudes of the day: \"The real powers in America are women---the wives and sweethearts behind the masculine dummies\....\" Highlights of the 1950s included the much-heralded marriage of Abner and Daisy Mae in 1952, the birth of their son \"Honest Abe\" Yokum in 1953, and in 1954 the introduction of Abner\'s enormous, long-lost kid brother Tiny Yokum, who filled Abner\'s place as a bachelor in the annual Sadie Hawkins Day race. In 1952, Capp and his characters graced the covers of both Life and TV Guide. The year 1956 saw the debut of Bald Iggle, considered by some Abner enthusiasts to be the creative high point of the strip, as well as Mammy\'s revelatory encounter with the \"Square Eyes\" Family---Capp\'s thinly-veiled appeal for racial tolerance. (This fable-like story was collected into an educational comic book called Mammy Yokum and the Great Dogpatch Mystery! and distributed by the Anti-Defamation League of B\'nai B\'rith later that year.) Two years later, Capp\'s studio issued Martin Luther King and the Montgomery Story, a biographical comic book distributed by the Fellowship of Reconciliation. Often, Capp had parodied corporate greed---pork tycoon J. Roaringham Fatback had figured prominently in wiping out the Shmoos. But in 1952, when General Motors president Charles E. Wilson, nominated for a cabinet post, told Congress \"\...what was good for the country was good for General Motors and vice versa\", he inspired one of Capp\'s greatest satires---the introduction of General Bullmoose, the robust, ruthless, and ageless business tycoon. The blustering Bullmoose, who seemed to own and control nearly everything, justified his far-reaching and mercenary excesses by saying \"What\'s good for General Bullmoose is good for the USA!\" Bullmoose\'s corrupt interests were often pitted against those of the pathetic Lower Slobbovians in a classic mismatch of \"haves\" versus \"have-nots\". This character, along with the Shmoos, helped cement Capp\'s favor with the Left, and increased their outrage a decade later when Capp, a former Franklin D. Roosevelt liberal, switched targets. Nonetheless, General Bullmoose continued to appear, undaunted and unredeemed, during the strip\'s final right-wing phase and into the 1970s. ## Feud with Ham Fisher {#feud_with_ham_fisher} After Capp quit his ghosting job on Ham Fisher\'s Joe Palooka in 1934 to launch his own strip, Fisher badmouthed him to colleagues and editors, claiming that Capp had \"stolen\" his idea. For years, Fisher brought the characters back to his strip, billing them as \"The ORIGINAL Hillbilly Characters\" and advising readers not to be \"fooled by imitations\". (In fact, Fisher\'s brutish hillbilly character---Big Leviticus, created by Capp in Fisher\'s absence---bore little resemblance to Li\'l Abner.) According to a November 1950 Time article, \"Capp parted from Fisher with a definite impression, (to put it mildly) that he had been underpaid and unappreciated. Fisher, a man of Roman self esteem, considered Capp an ingrate and a whippersnapper, and watched his rise to fame with unfeigned horror.\" \"Fisher repeatedly brought Leviticus and his clan back, claiming their primacy as comics\' first hillbilly family -- but he was missing the point. It wasn\'t the setting that made Capp\'s strip such a huge success. It was Capp\'s finely tuned sense of the absurd, his ability to milk an outrageous situation for every laugh in it and then, impossibly, to squeeze even more laughs from it, that found such favor with the public,\" (from Don Markstein\'s Toonopedia). The Capp-Fisher feud was well known in cartooning circles, and it grew more personal as Capp\'s strip eclipsed Joe Palooka in popularity. Fisher hired away Capp\'s top assistant, Moe Leff. After Fisher underwent plastic surgery, Capp included a racehorse in Li\'l Abner named \"Ham\'s Nose-Bob\". In 1950, Capp introduced a cartoonist character named \"Happy Vermin\"---a caricature of Fisher---who hired Abner to draw his comic strip in a dimly lit closet (after sacking his previous \"temporary\" assistant of 20 years, who had been cut off from all his friends in the process). Instead of using Vermin\'s tired characters, Abner inventively peopled the strip with hillbillies. A bighearted Vermin told his slaving assistant: \"I\'m proud of having created these characters!! They\'ll make millions for me!! And if they do -- I\'ll get you a new light bulb!!\" Traveling in the same social circles, the two men engaged in a 20-year mutual vendetta, as described by the New York Daily News in 1998: \"They crossed paths often, in the midtown watering holes and at National Cartoonists Society banquets, and the city\'s gossip columns were full of their snarling public donnybrooks.\" In 1950, Capp wrote a nasty article for The Atlantic, entitled \"I Remember Monster\". The article recounted Capp\'s days working for an unnamed \"benefactor\" with a miserly, swinish personality, who Capp claimed was a never-ending source of inspiration when it came time to create a new unregenerate villain for his comic strip. The thinly-veiled boss was understood to be Ham Fisher. Fisher retaliated, doctoring photostats of Li\'l Abner and falsely accusing Capp of sneaking obscenities into his comic strip. Fisher submitted examples of Li\'l Abner to Capp\'s syndicate and to the New York courts, in which Fisher had identified pornographic images that were hidden in the background art. However, the X-rated material had been drawn there by Fisher. Capp was able to refute the accusation by simply showing the original artwork. In 1954, when Capp was applying for a Boston television license, the Federal Communications Commission (FCC) received an anonymous packet of pornographic Li\'l Abner drawings. The National Cartoonists Society (NCS) convened an ethics hearing, and Fisher was expelled for the forgery from the same organization that he had helped found; Fisher\'s scheme had backfired in spectacular fashion. Around the same time, his mansion in Wisconsin was destroyed by a storm. On December 27, 1955, Fisher committed suicide in his studio. The feud and Fisher\'s suicide were used as the basis for a lurid, highly fictionalized murder mystery, Strip for Murder by Max Allan Collins. Another \"feud\" seemed to be looming when, in one run of Sunday strips in 1957, Capp lampooned the comic strip Mary Worth as \"Mary Worm\". The title character was depicted as a nosy, interfering busybody. Allen Saunders, the creator of the Mary Worth strip, returned Capp\'s fire with the introduction of the character \"Hal Rapp\", a foul-tempered, ill-mannered, and (ironically, as Capp was a teetotaler) inebriated cartoonist. Later, the \"feud\" was revealed to be a collaborative hoax that Capp and his longtime pal Saunders had cooked up together. The Capp-Saunders \"feud\" fooled both editors and readers, generated plenty of free publicity for both strips---and Capp and Saunders had a good laugh when all was revealed. ## Production methods {#production_methods} Like many cartoonists, Capp made extensive use of assistants (notably Andy Amato, Harvey Curtis, Walter Johnson, and Frank Frazetta). During the extended peak of the strip, the workload grew to include advertising, merchandising, promotional work, public service comics, and other specialty work---in addition to the regular six dailies and one Sunday strip per week. From the early 1940s to the late 1950s, there were scores of Sunday strip-style magazine ads for Cream of Wheat using the Abner characters, and in the 1950s, Fearless Fosdick became a spokesman for Wildroot Cream-Oil hair tonic in a series of daily strip-style print ads. The characters also sold chainsaws, underwear, ties, detergent, candy, soft drinks---including a licensed version of Capp\'s moonshine creation, Kickapoo Joy Juice---and General Electric and Procter & Gamble products, all requiring special artwork. No matter how much help he had, Capp insisted on his drawing and inking the characters\' faces and hands---especially of Abner and Daisy Mae---and his distinctive touch is often discernible. \"He had the touch,\" Frazetta said of Capp in 2008. \"He knew how to take an otherwise ordinary drawing and really make it pop. I\'ll never knock his talent.\" As is usual with collaborative efforts in comic strips, his name was the only one credited--- although, sensitive to his own experience working on Joe Palooka, Capp frequently drew attention to his assistants in interviews and publicity pieces. A 1950 cover story in Time even included photographs of two of his employees, whose roles in the production were detailed by Capp. Ironically, this highly irregular policy (along with the subsequent fame of Frank Frazetta) has led to the misconception that his strip was \"ghosted\" by other hands. The production of Li\'l Abner has been well documented, however. In point of fact, Capp maintained creative control over every stage of production for virtually the entire run of the strip. Capp originated the stories, wrote the dialogue, designed the major characters, rough penciled the preliminary staging and action of each panel, oversaw the finished pencils, and drew and inked the hands and faces of the characters. Frazetta authority David Winiewicz described the everyday working mode of operation in Li\'l Abner Dailies: 1954 Volume 20 (Kitchen Sink, 1994): There was also a separate line of comic book titles published by the Caplin family-owned Toby Press, including Shmoo Comics featuring Washable Jones. Cartoonist Mell Lazarus, creator of Miss Peach and Momma, wrote a comic novel in 1963 entitled The Boss Is Crazy, Too which was partly inspired by his apprenticeship days working with Capp and his brother Elliot at Toby. In a seminar at the Charles Schulz Museum on November 8, 2008, Lazarus called his experience at Toby \"the five funniest years of my life\". Lazarus went on to cite Capp as one of the \"four essentials\" in the field of newspaper cartoonists, along with Walt Kelly, Charles Schulz, and Milton Caniff. Capp detailed his approach to writing and drawing the stories in an instructional course book for the Famous Artists School, beginning in 1956. In 1959, Capp recorded and released an album for Folkways Records (now owned by the Smithsonian) on which he identified and described \"The Mechanics of the Comic Strip\". Frazetta, later famous as a fantasy artist, assisted on the strip from 1954 to December 1961. Fascinated by Frazetta\'s abilities, Capp initially gave him a free hand in an extended daily sequence (about a biker named \"Frankie\", a caricature of Frazetta) to experiment with the basic look of the strip by adding a bit more realism and detail (particularly to the inking). After editors complained about the stylistic changes, the strip\'s previous look was restored. During most of his tenure with Capp, Frazetta\'s primary responsibility---along with various specialty art, such as a series of Li\'l Abner greeting cards---was tight-penciling the Sunday pages from studio roughs. This work was collected by Dark Horse Comics in a four-volume hardcover series entitled Al Capp\'s Li\'l Abner: The Frazetta Years. In 1961, Capp, complaining of declining revenue, wanted to have Frazetta continue with a 50% pay cut. \"\[Capp\] said he would cut the salary in half. Goodbye. That was that. I said goodbye,\" (from Frazetta: Painting with Fire). However, Frazetta returned briefly a few years later to draw a public service comic book called Li\'l Abner and the Creatures from Drop-Outer Space, distributed by the Job Corps in 1965. ## Personality Although he was often considered a difficult person, some acquaintances of Capp have stressed that the cartoonist also had a sensitive side. In 1973, upon learning that 12-year-old Ted Kennedy Jr., the son of his political rival Ted Kennedy Sr., had his right leg amputated, Capp wrote the boy an encouraging letter that gave candid advice about dealing with the loss of a limb, which Capp himself had experienced as a boy. One of Capp\'s grandchildren recalls that at one point, tears were streaming down the cartoonist\'s cheeks while he was watching a documentary about the Jonestown massacre. Capp gave money anonymously to charities and \"people in need\" at various points in his life. ## Sexual harassment and assault claims {#sexual_harassment_and_assault_claims} Two biographies, one of Grace Kelly and the other of Goldie Hawn, describe Capp as trying to force the younger women to have sex with him. While no firsthand allegation has ever surfaced regarding Kelly, in her autobiography, Hawn stated that Capp sexually propositioned her on a casting couch and exposed himself to her when she was 19 years old. When she refused his advances, Capp became angry and told her that she was \"never gonna make anything in your life\" and that she should \"go and marry a Jewish dentist. You\'ll never get anywhere in this business.\" In 1971, investigative journalist Jack Anderson wrote that Capp had exposed his genitals to four female students at the University of Alabama. In 1972, after an incident at the University of Wisconsin--Eau Claire, Capp was arrested. He pleaded guilty to a charge of attempted adultery, while charges of indecent exposure and sodomy were dropped. He was fined US\$500 (`{{Inflation\|US\|500\|1972\|fmt=eq}}`{=mediawiki}). In 2019, Jean Kilbourne was inspired by the MeToo movement to publish in Hogan\'s Alley her own experience of being groped and sexually solicited by Al Capp while doing freelance writing and research work for him in contemplation of a permanent job in 1967. ## Public service works {#public_service_works} Capp provided specialty artwork for civic groups, government agencies, and charitable or nonprofit organizations, spanning several decades. The following titles are all single-issue, educational comic books and pamphlets produced for various public services: - Al Capp by Li\'l Abner--- Public service giveaway issued by the Red Cross (1946) - Yo\' Bets Yo\' Life!--- Public service giveaway issued by the U.S. Army (c. 1950) - Li\'l Abner Joins the Navy--- Public service giveaway issued by the Dept. of the Navy (1950) - Fearless Fosdick and the Case of the Red Feather--- Public service giveaway issued by Red Feather Services, a forerunner of United Way (1951) - The Youth You Supervise--- Public service giveaway issued by the U.S. Department of Labor (1956) - Mammy Yokum and the Great Dogpatch Mystery!--- Public service giveaway issued by the Anti-Defamation League of B\'nai B\'rith (1956) - Operation: Survival!--- Public service giveaway issued by the Dept. of Civil Defense (1957) - Natural Disasters!--- Public service giveaway issued by the Department of Civil Defense (1957) - Martin Luther King and the Montgomery Story--- Public service giveaway issued by The Fellowship of Reconciliation (1958) - Li\'l Abner and the Creatures from Drop-Outer Space--- Public service giveaway issued by the Job Corps (1965) - Statue of Josiah Flintabattey Flonatin--- design of a statue for the northern Manitoba city of Flin Flon\'s mascot \[City of Flin Flon\'s tribute [1](https://www.cityofflinflon.ca/p/-statue-of-josiah-flintabattey-flonatin)\] (1962) In addition, Dogpatch characters were used in national campaigns for the U.S. Treasury, the Cancer Foundation, the March of Dimes, the National Heart Fund, the Sister Kenny Foundation, the Boy Scouts of America, Community Chest, the National Reading Council, Minnesota Tuberculosis and Health Association, Christmas Seals, the National Amputation Foundation, and Disabled American Veterans, among others. ## Public figure {#public_figure} In the Golden Age of the American comic strip, successful cartoonists received a great deal of attention; their professional and private lives were reported in the press, and their celebrity was often nearly sufficient to rival their creations. As Li\'l Abner reached its peak years, and following the success of the Shmoos and other high moments in his work, Al Capp achieved a public profile that is still unparalleled in his profession, and arguably exceeded the fame of his strip. \"Capp was the best known, most influential and most controversial cartoonist of his era,\" writes publisher (and leading Shmoo collector) Denis Kitchen. \"His personal celebrity transcended comics, reaching the public and influencing the culture in a variety of media. For many years he simultaneously produced the daily strip, a weekly syndicated newspaper column, and a 500-station radio program \...\" He ran the Boston Summer Theatre with The Phantom cartoonist Lee Falk, bringing in Hollywood actors such as Mae West, Melvyn Douglas, and Claude Rains to star in their live productions. He even briefly considered running for a Massachusetts Senate seat. Vice President Spiro Agnew urged Capp to run in the Democratic Party Massachusetts primary in 1970 against Ted Kennedy, but Capp ultimately declined. (He did, however, donate his services as a speaker at a \$100-a-plate fundraiser for Republican Congressman Jack Kemp.) Besides his use of the comic strip to voice his opinions and display his humor, Capp was a popular guest speaker at universities, and on radio and television. He remains the only cartoonist to be embraced by television; no other comic artist to date has come close to Capp\'s televised exposure. Capp appeared as a regular on The Author Meets the Critics (1948--\'54) and made regular, weekly appearances on Today in 1953. He was also a periodic panelist on ABC and NBC\'s Who Said That? (1948--\'55), and co-hosted DuMont\'s What\'s the Story? (1953). Between 1952 and 1972, he hosted at least five television shows--three different talk shows called The Al Capp Show (1952 and 1968) and Al Capp (1971--\'72), Al Capp\'s America (a live \"chalk talk\", with Capp providing a barbed commentary while sketching cartoons, 1954), and a CBS game show called Anyone Can Win (1953). He also hosted similar vehicles on the radio---and was a familiar celebrity guest on various other broadcast programs, including NBC Radio\'s long-running Monitor with its famous Monitor Beacon audio signature, as a commentator dubbed \"An expert of nothing with opinions on everything.\" His frequent appearances on NBC\'s The Tonight Show spanned three emcees (Steve Allen, Jack Paar, and Johnny Carson), from the 1950s to the 1970s. One memorable story, as recounted to Johnny Carson, was about his meeting with then-President Dwight D. Eisenhower. As Capp was ushered into the Oval Office, his prosthetic leg suddenly collapsed into a pile of disengaged parts and hinges on the floor. The President immediately turned to an aide and said, \"Call Walter Reed (Hospital), or maybe Bethesda,\" to which Capp replied, \"Hell no, just call a good local mechanic!\" (Capp also spoofed Carson in his strip, in a 1970 episode called \"The Tommy Wholesome Show\".) Capp portrayed himself in a cameo role in the Bob Hope film That Certain Feeling, for which he also provided promotional art. He was interviewed live on Person to Person on November 27, 1959, by host Charles Collingwood. He also appeared as himself on The Ed Sullivan Show, Sid Caesar\'s Your Show of Shows, The Red Skelton Show, The Merv Griffin Show, The Mike Douglas Show, and guested on Ralph Edwards\' This Is Your Life on February 12, 1961, with honoree Peter Palmer (the actor who played Li\'l Abner in the Paramount film). Capp also freelanced very successfully as a magazine writer and newspaper columnist, in a wide variety of publications including Life, Show, Pageant, The Atlantic, Esquire, Coronet, and The Saturday Evening Post. Capp was impersonated by comedians Rich Little and David Frye. Although Capp\'s endorsement activities never rivaled Li\'l Abner\'s or Fearless Fosdick\'s, he was a celebrity spokesman in print ads for Sheaffer Snorkel fountain pens (along with colleagues and close friends Milton Caniff and Walt Kelly), and---with an irony that became apparent later---a brand of cigarettes (Chesterfield). Capp resumed visiting war amputees during the Korean War and Vietnam War. He toured Vietnam with the USO, entertaining troops along with Art Buchwald and George Plimpton. He served as chairman of the Cartoonists\' Committee in President Dwight D. Eisenhower\'s People-to-People program in 1954 (although Capp had supported Adlai Stevenson for president in 1952 and 1956), which was organized to promote Savings bonds for the U.S. Treasury. Capp had earlier provided the Shmoo for a special Children\'s Savings Bond in 1949, accompanying President Harry S. Truman at the bond\'s unveiling ceremony. During the Soviet Union\'s blockade of West Berlin in 1948, the commanders of the Berlin airlift had cabled Capp, requesting inflatable shmoos as part of \"Operation: Little Vittles\". Candy-filled shmoos were air-dropped to hungry West Berliners by America\'s 17th Military Airport Squadron during the humanitarian effort. \"When the candy-chocked shmoos were dropped, a near-riot resulted,\" (reported in Newsweek---October 11, 1948). In addition to his public service work for charitable organizations for disabled people, Capp also served on the National Reading Council, which was organized to combat illiteracy. He published a column (\"Wrong Turn Onto Sesame Street\") challenging federally funded public television endowments in favor of educational comics---which, according to Capp, \"didn\'t cost a dime in taxes and never had. I pointed out that a kid could enjoy Sesame Street without learning how to read, but he couldn\'t enjoy comic strips unless he could read; and that a smaller investment in getting kids to read by supplying them with educational matter in such reading form might make better sense.\" Capp\'s academic interests included being one of nineteen original \"Trustees and Advisors\" for \"Endicott, Junior College for Young Woman\", located in Pride\'s Crossing (Beverly), Massachusetts, which was founded in 1939. Al Capp is listed in the 1942 Mingotide Yearbook, representing the first graduating class from what is now the 4-year school known as Endicott College. The yearbook entry includes his credential as a \"Cartoonist for United Feature Syndicate\" and a resident of New York City. \"Comics\", wrote Capp in 1970, \"can be a combination of the highest quality of art and text, and many of them are.\" Capp produced many giveaway educational comic books and public services pamphlets, spanning several decades, for the Red Cross, the Department of Civil Defense, the Department of the Navy, the U.S. Army, the Anti-Defamation League, the Department of Labor, Community Chest (a forerunner of United Way), and the Job Corps. Capp\'s studio provided special artwork for various civic groups and nonprofit organizations as well. Dogpatch characters were used in national campaigns for the Cancer Foundation, the March of Dimes, the National Heart Fund, the Boy Scouts of America, Minnesota Tuberculosis and Health Association, the National Amputation Foundation, and Disabled American Veterans, among others. They were also used to help sell Christmas Seals. In the early 1960s, Capp regularly wrote a column entitled Al Capp\'s Column for the newspaper The Schenectady Gazette (currently The Daily Gazette). He was the Playboy interview subject in December 1965, in a conversation conducted by Alvin Toffler. In August 1967, Capp was the narrator and host of an ABC network special called Do Blondes Have More Fun? In 1970, he was the subject of a provocative NBC documentary called This Is Al Capp. ## The 1960s and 1970s {#the_1960s_and_1970s} Capp and his family lived in Cambridge, Massachusetts, near Harvard University, during the entire Vietnam War protest era. The turmoil that Americans were watching on their television sets was happening live---right in his own neighborhood. Campus radicals and \"hippies\" inevitably became one of Capp\'s favorite targets in the sixties. Alongside his long-established caricatures of right-wing, big business types such as General Bullmoose and J. Roaringham Fatback, Capp began spoofing counterculture icons such as Joan Baez (in the character of Joanie Phoanie, a wealthy folksinger who offers an impoverished orphanage ten thousand dollars\' worth of \"protest songs\"). The sequence implicitly labeled Baez a limousine liberal, a charge she took to heart, as detailed years later in her 1987 autobiography, And A Voice To Sing With: A Memoir. Another target was Senator Ted Kennedy, parodied as \"Senator O. Noble McGesture\", resident of \"Hyideelsport\". The town name is a play on Hyannisport, Massachusetts, where a number of the Kennedy clan have lived. Capp became a popular public speaker on college campuses, where he reportedly relished hecklers. He attacked militant antiwar demonstrators, both in his personal appearances and in his strip. He also satirized student political groups. The Youth International Party (YIP) and Students for a Democratic Society (SDS) emerged in Li\'l Abner as \"Students Wildly Indignant about Nearly Everything!\" (SWINE). In an April 1969 letter to Time, Capp insisted, \"The students I blast are not the dissenters, but the destroyers---the less than 4% who lock up deans in washrooms, who burn manuscripts of unpublished books, who make combination pigpens and playpens of their universities. The remaining 96% detest them as heartily as I do.\" Capp\'s increasingly controversial remarks at his campus speeches and during television appearances cost him his semi-regular spot on the Tonight Show. His contentious public persona during this period was captured on a late sixties comedy LP called Al Capp On Campus. The album features his interaction with students at Fresno State College (now California State University, Fresno) on such topics as \"sensitivity training\", \"humanitarianism\", \"abstract art\" (Capp hated it), and \"student protest\". The cover features a cartoon drawing by Capp of wildly dressed, angry hippies carrying protest signs with slogans like \"End Capp Brutality\", \"Abner and Daisy Mae Smoke Pot\", \"Capp Is Over \[30, 40, 50---all crossed out\] the Hill!!\", and \"If You Like Crap, You\'ll Like Capp!\" Highlights of the strip\'s final decades include the stories \"Boomchik\" (1961), in which America\'s international prestige is saved by Mammy Yokum, \"Daisy Mae Steps Out\" (1966), a female-empowering tale of Daisy\'s brazenly audacious \"homewrecker gland\", \"The Lips of Marcia Perkins\" (1967), a satirical, thinly-veiled commentary on venereal disease and public health warnings, \"Ignoble Savages\" (1968), in which the Mob takes over Harvard, and \"Corporal Crock\" (1973), in which Bullmoose reveals his reactionary cartoon role model, in a tale of obsession and the fanatical world of comic book collecting. The cartoonist visited John Lennon and Yoko Ono at their 1969 Bed-In for Peace in Montreal, and their testy exchange later appeared in the documentary film Imagine: John Lennon (1988). Introducing himself with the words \"I\'m a dreadful Neanderthal fascist. How do you do?\", Capp sardonically congratulated Lennon and Ono on their Two Virgins nude album cover: \"I think that everybody owes it to the world to prove they have pubic hair. You\'ve done it, and I tell you that I applaud you for it.\" Following this exchange, Capp insulted Ono (\"Good God, you\'ve gotta live with that?\"), and was asked to \"get out\" by Lennon publicist Derek Taylor. Lennon allowed him to stay, however, but the conversation had soured considerably. On Capp\'s exit, Lennon sang an impromptu version of his song \"The Ballad of John and Yoko\" with a slightly revised, but nonetheless prophetic lyric: \"Christ, you know it ain\'t easy / You know how hard it can be / The way things are goin\' / They\'re gonna crucify Capp! \" Despite his political conservatism in the last decade of his life, Capp is reported to have been liberal in some particular causes; he supported gay rights, and did not tolerate any attempts at homophobic jokes. He is also said to have supported Martin Luther King Jr. and the fight for racial equality in American society, although he was very sceptical of the tactics of the Black Panthers and Malcolm X. In 1968, a theme park called Dogpatch USA opened at Marble Falls, Arkansas, based on Capp\'s work and with his support. The park was a popular attraction during the 1970s, but was abandoned in 1993 due to financial difficulties. By 2005, the area once devoted to a live-action facsimile of Dogpatch (including a lifesize statue in the town square of Dogpatch \"founder\" General Jubilation T. Cornpone) had been heavily stripped by vandals and souvenir hunters, and was slowly being reclaimed by the surrounding Arkansas wilderness. On April 22, 1971, syndicated columnist Jack Anderson reported allegations that in February 1968 Capp had made indecent advances to four female students when he was invited to speak at the University of Alabama. Anderson and an associate confirmed that Capp was shown out of town by university police, but that the incident had been hushed up by the university to avoid negative publicity. The following month, Capp was charged in Eau Claire, Wisconsin, in connection with another alleged incident following his April 1 lecture at the University of Wisconsin-Eau Claire. Capp was accused of propositioning a married woman in his hotel room. Although no sexual act was alleged to have resulted, the original charge included \"sodomy\". As part of a plea agreement, Capp pleaded guilty to the charge of \"attempted adultery\" (adultery was a felony in Wisconsin), and the other charges were dropped. Capp was fined \$500 and court costs. In a December 1992 article for The New Yorker, Seymour Hersh reported that President Richard Nixon and Charles Colson had repeatedly discussed the Capp case in Oval Office recordings that had recently been made available by the National Archives. Nixon and Capp were on friendly terms, Hersh wrote, and Nixon and Colson had worked to find a way for Capp to run against Ted Kennedy for the U.S. Senate. \"Nixon was worried about the allegations, fearing that Capp\'s very close links to the White House would become embarrassingly public\", Hersh wrote. \"The White House tapes and documents show that he and Colson discussed the issue repeatedly, and that Colson eventually reassured the president by saying that he had, in essence, fixed the case. Specifically, the president was told that one of Colson\'s people had gone to Wisconsin and tried to talk to the prosecutors.\" Colson\'s efforts failed, however. The Eau Claire district attorney, a Republican, refused to dismiss the attempted adultery charge. In passing sentence in February 1972, the judge rejected the D.A.\'s motion that Capp agree to undergo psychiatric treatment. The resulting publicity led to hundreds of papers dropping his comic strip, and Capp, already in failing health, withdrew from public speaking. Celebrity biographer James Spada has claimed that similar allegations were made by actress Grace Kelly. However, no firsthand allegation has ever surfaced. \"From beginning to end, Capp was acid-tongued toward the targets of his wit, intolerant of hypocrisy, and always wickedly funny. After about 40 years, however, Capp\'s interest in Abner waned, and this showed in the strip itself,\" according to Don Markstein\'s Toonopedia. Although Capp had used assistants on the strip practically since the beginning, in the final years his own involvement in the strip decreased. His health issues made it increasingly difficult for Capp to work, recalled his assistants. On November 13, 1977, Capp retired with an apology to his fans for the recently declining quality of the strip, which he said had been the best he could manage due to declining health. \"If you have any sense of humor about your strip---and I had a sense of humor about mine---you knew that for three or four years Abner was wrong. Oh hell, it\'s like a fighter retiring. I stayed on longer than I should have,\" he admitted, adding that he couldn\'t breathe anymore. \"When he retired Li\'l Abner, newspapers ran expansive articles and television commentators talked about the passing of an era. People magazine ran a substantial feature, and even the comics-free New York Times devoted nearly a full page to the event\", wrote publisher Denis Kitchen. Capp\'s final years were marked by advancing illness and by family tragedy. In October 1977, one of his two daughters died; a few weeks later, a beloved granddaughter was killed in a car accident. A lifelong chain smoker, Capp died in 1979 from emphysema at his home in South Hampton, New Hampshire. Capp is buried in Mount Prospect Cemetery in Amesbury, Massachusetts. Engraved on his headstone is a stanza from Thomas Gray: The plowman homeward plods his weary way / And leaves the world to darkness and to me (from Elegy Written in a Country Churchyard, 1751). ## Legacy \"Neither the strip\'s shifting political leanings nor the slide of its final few years had any bearing on its status as a classic; and in 1995, it was recognized as such by the U.S. Postal Service\", according to Toonopedia. Li\'l Abner was one of 20 American comic strips included in the Comic Strip Classics series of USPS commemorative stamps. Al Capp, an inductee into the National Cartoon Museum (formerly the International Museum of Cartoon Art), is one of only 31 artists selected to their Hall of Fame. Capp was also inducted into the Will Eisner Award Hall of Fame in 2004. Sadie Hawkins Day and double whammy are two terms attributed to Al Capp that have entered the English language. Other, less ubiquitous Cappisms include skunk works and Lower Slobbovia. The term shmoo also has entered the lexicon, defining highly technical concepts in no fewer than four separate fields of science, including the variations shmooing (a microbiological term for the \"budding\" process in yeast reproduction), and shmoo plot (a technical term in the field of electrical engineering). In socioeconomics, a \"shmoo\" refers to any generic kind of good that reproduces itself, (as opposed to \"widgets\" which require resources and active production). In the field of particle physics, \"shmoo\" refers to a high energy survey instrument, as used at the Los Alamos National Laboratory to capture subatomic cosmic ray particles emitted from the Cygnus X-3 constellation. Capp also had a knack for popularizing certain uncommon terms, such as druthers, schmooze, and nogoodnik, neatnik, etc. In his book The American Language, H.L. Mencken credits the postwar mania for adding \"-nik\" to the ends of adjectives to create nouns as beginning---not with beatnik or Sputnik---but earlier, in the pages of Li\'l Abner. Al Capp\'s life and career are the subjects of a new life-sized mural commemorating the 100th anniversary of his birth. Created by resident artist Jon P. Mooers, the mural was unveiled in downtown Amesbury on May 15, 2010. According to the Boston Globe (as reported on May 18, 2010), the town has renamed its amphitheater in the artist\'s honor, and is looking to develop an Al Capp Museum. Capp is also the subject of an upcoming WNET-TV American Masters documentary, The Life and Times of Al Capp, produced by his granddaughter, independent filmmaker Caitlin Manning. Since his death in 1979, Al Capp and his work have been the subject of more than 40 books, including three biographies. Underground cartoonist and Li\'l Abner expert Denis Kitchen has published, co-published, edited, or otherwise served as consultant on nearly all of them. Kitchen is currently compiling a biographical monograph on Al Capp. At San Diego Comic-Con in July 2009, IDW announced the upcoming publication of Al Capp\'s Li\'l Abner: The Complete Dailies and Color Sundays as part of their ongoing The Library of American Comics series. The comprehensive series, a reprinting of the entire 43-year history of Li\'l Abner, spanning a projected 20 volumes, began on April 7, 2010.	2025-06-20T00:00:00
3,013	Ann Druyan	Ann Druyan (`{{IPAc-en\|d\|r\|iː\|'\|æ\|n}}`{=mediawiki} `{{respell\|dree\|ANN}}`{=mediawiki}; born June 13, 1949) is an American documentary producer and director specializing in the communication of science. She co-wrote the 1980 PBS documentary series Cosmos, hosted by Carl Sagan, whom she married in 1981. She is the creator, producer, and writer of the 2014 sequel, Cosmos: A Spacetime Odyssey and its sequel series, Cosmos: Possible Worlds, as well as the book of the same name. She directed episodes of both series. In the late 1970s, she became the creative director of NASA\'s Voyager Interstellar Message Project, which produced the golden discs affixed to both the Voyager 1 and Voyager 2 spacecraft. She also published a novel, A Famous Broken Heart, in 1977, and later co-wrote several best selling non-fiction books with Sagan. ## Early life and education {#early_life_and_education} Ann Druyan was born in Queens, New York, the daughter of Pearl A. (`{{nee\|Goldsmith}}`{=mediawiki}) and Harry Druyan, who co-owned a knitwear firm. Her family was Jewish. Druyan\'s early interest in math and science was, in her word, \"derailed\" when a junior high-school teacher ridiculed a question she asked about the universality of `{{pi}}`{=mediawiki}. \"I raised my hand and said, \'You mean this applies to every circle in the universe?\', and the teacher told me not to ask stupid questions. And there I was having this religious experience, and she made me feel like such a fool. I was completely flummoxed from then on until after college.\" Druyan characterized her three years at New York University as \"disastrous\", and it was only after she left school without graduating that she discovered the pre-Socratic philosophers and began educating herself, thus leading to a renewed interest in science. ## Career In the late 1970s, Druyan became the creative director of NASA\'s Voyager Interstellar Message Project. As creative director, Druyan worked with a team to design a complex message, including music and images, for possible alien civilizations. These golden phonograph records affixed to the Voyager 1 and Voyager 2 spacecraft are now beyond the outermost planets of the Solar System, and Voyager 1 has entered interstellar space. Both records have a projected shelf life of one billion years. Druyan\'s role on the project was discussed on the July 8, 2018, 60 Minutes segment \"The Little Spacecraft That Could\". In the segment, Druyan explained her insistence that Chuck Berry\'s \"Johnny B. Goode\" be included on the Golden Record, saying: \"\...Johnny B. Goode, rock and roll, was the music of motion, of moving, getting to someplace you\'ve never been before, and the odds are against you, but you want to go. That was Voyager.\" The segment also discussed Sagan\'s suggestion, in 1990, that Voyager 1 turn its cameras back towards Earth to take a series of photographs showing the planets of the Solar System. The shots, showing Earth from a distance of 3.7 billion miles as a small point of bluish light, became the basis for Sagan\'s famous \"Pale Blue Dot\" passage, first published in Pale Blue Dot: A Vision of the Human Future in Space (1994). During that time, Druyan also co-wrote (with Carl Sagan and Steven Soter) the 1980 PBS documentary series Cosmos, hosted by Carl Sagan. The thirteen-part series covered a wide range of scientific subjects, including the origin of life and a perspective of humans place in the universe. It was highly acclaimed, and became the most widely watched series in the history of American public television at that time. The series won two Emmys and a Peabody Award, and has since been broadcast in more than 60 countries and seen by over 500 million people. A book was also published to accompany the series. `{{As of \|2009}}`{=mediawiki}, it is still the most widely watched PBS series in the world. Several revised versions of the series were later broadcast; one version, telecast after Sagan\'s death, opens with Druyan paying tribute to her late husband and the impact of Cosmos over the years. Druyan wrote and produced the 1987 PBS NOVA episode \"Confessions of a Weaponeer\" on the life of President Eisenhower\'s Science Advisor George Kistiakowsky. In 2000, Druyan, together with Steve Soter, co-wrote Passport to the Universe, the inaugural planetarium show for the Rose Center for Earth and Space at the American Natural History Museum\'s Hayden Planetarium. The attraction is narrated by Tom Hanks. Druyan and Soter also co-wrote The Search for Life: Are We Alone, narrated by Harrison Ford, which also debuted at the Hayden\'s Rose Center. In 2000, Druyan co-founded Cosmos Studios, Inc, with Joseph Firmage. As CEO of Cosmos Studios, Druyan produces science-based entertainment for all media. In addition to Cosmos: A SpaceTime Odyssey, Cosmos Studios has produced Cosmic Africa, Lost Dinosaurs of Egypt, and the Emmy-nominated documentary Cosmic Journey: The Voyager Interstellar Mission and Message. In 2009, she distributed a series of podcasts called At Home in the Cosmos with Annie Druyan, in which she described her works, the life of her husband, Carl Sagan, and their marriage. Druyan is credited, with Carl Sagan, as the co-creator and co-producer of the 1997 feature film Contact. In 2011, it was announced that Druyan would executive produce, co-write, and be one of the episodic directors for a sequel to Cosmos: A Personal Voyage, to be called Cosmos: A Spacetime Odyssey, which began airing in March 2014. Episodes premiered on Fox and also aired on National Geographic Channel on the following night. At the time of its release, Fox gave the series the largest global rollout of a television series ever, debuting it in 180 countries. The premiere episode was shown across nine of Fox\'s cable properties in addition to the broadcast network in a \"roadblock\" style premiere. The series went on to become the most-watched series ever for National Geographic Channel International, with at least some part of the 13-episode series watched by 135 million people, including 45 million in the U.S. In March 2020, a third season of Cosmos, named Cosmos: Possible Worlds, for which Druyan was executive producer, writer, and director, premiered on National Geographic. Druyan also said: \"I very much have season four in mind, and I know what it\'s going to be. And I even know some of the stories that I want to tell in it.\" ### Writing Druyan\'s first novel, A Famous Broken Heart, was published in 1977. Druyan co-wrote six New York Times bestsellers with Carl Sagan, including: Comet, Shadows of Forgotten Ancestors, and The Demon-Haunted World. She is co-author, along with Carl Sagan, F. D. Drake, Timothy Ferris, Jon Lomberg and Linda Salzman Sagan, of Murmurs Of Earth: The Voyager Interstellar Record. She also wrote the updated introduction to Sagan\'s book The Cosmic Connection and the epilogue of Billions and Billions. She wrote the introduction to, and edited The Varieties of Scientific Experience, published from Sagan\'s 1985 Gifford lectures. In February 2020, Druyan published Cosmos: Possible Worlds, a companion volume to the television series of the same name, which premiered in March 2020. ### Work in science {#work_in_science} Druyan is a fellow of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP). Druyan served as program director of the first solar-sail deep-space mission, Cosmos 1, launched on a Russian ICBM in 2005. Druyan is involved in multiple Breakthrough Initiatives. With Frank Drake, Druyan is the co-chair of Breakthrough Message and also a member of Breakthrough Starshot. She is a member of the advisory board of The Carl Sagan Institute. ## Activism Druyan has for many years been a vocal advocate for nuclear disarmament. She was arrested three times at the Mercury, Nevada nuclear test site during Mikhail Gorbachev\'s unilateral moratorium on underground nuclear testing, with which President Ronald Reagan did not cooperate. This included an arrest in June 1986, when she crossed a white painted line indicating the test site\'s boundary. Sagan, who attended the same protest with Druyan, was not arrested. In the early 1990s, Druyan worked with Sagan and then-Senator Al Gore Jr. and a host of religious and scientific leaders to bring the scientific and religious worlds together in a unified effort to preserve the environment, resulting in the Declaration of the \'Mission to Washington{{\'}}. She was a founding director of the Children\'s Health Fund until the spring of 2004, a project that provides mobile pediatric care to homeless and disadvantaged children in more than half a dozen cities. She is currently a member of their advisory board. She has been on the board of directors of the National Organization for the Reform of Marijuana Laws (NORML) for over 10 years and was its president from 2006 to 2010. ## Honors An asteroid discovered in 1988 was named in Druyan\'s honor by its discoverer Eleanor F. Helin. In a 2020 interview with Skeptical Inquirer, Druyan discussed 4970 Druyan and the asteroid named after her late husband, saying that 4970 Druyan is in a \"wedding ring orbit\" around the Sun with 2709 Sagan. Druyan was presented with a plaque on Sagan\'s sixtieth birthday, which is inscribed: \"Asteroid 2709 Sagan in eternal companion orbit with asteroid 4970 Druyan, symbolic of their love and admiration for each other.\" In November 2006, Druyan was a speaker at \"Beyond Belief: Science, Religion, Reason and Survival\". In January 2007, she was a juror at the 2007 Sundance Film Festival, responsible for selecting the winner of the Alfred P. Sloan Prize for films about science and technology. In November 2007, Druyan was awarded the title of \"Humanist Laureate\" by the International Academy of Humanism. In October 2019, the Center for Inquiry West opened the Carl Sagan--Ann Druyan Theater in Los Angeles. ## Religious and philosophical views {#religious_and_philosophical_views} In an interview with Joel Achenbach of The Washington Post, Druyan said that her early interest in science stemmed from a fascination with Karl Marx. Achenbach commented that \"She had, at the time, rather vaporous standards of evidence\", a reference to her belief in the ancient astronauts of Erich von Däniken and the theories of Immanuel Velikovsky pertaining to the solar system. Concerning the death of her husband she stated: > When my husband died, because he was so famous and known for not being a believer, many people would come up to me---it still sometimes happens---and ask me if Carl changed at the end and converted to a belief in an afterlife. They also frequently ask me if I think I will see him again. Carl faced his death with unflagging courage and never sought refuge in illusions. The tragedy was that we knew we would never see each other again. I don\'t ever expect to be reunited with Carl. ## Personal life {#personal_life} Druyan and Sagan\'s working and resulting romantic relationship has been the subject of numerous treatments in popular culture, including the Radiolab episode \"Carl Sagan and Ann Druyan\'s Ultimate Mix Tape\", a segment of the Comedy Central program Drunk History{{\'}}s episode \"Space\", and the song \"Sounds of Earth\" by Jim Moray. The asteroid 4970 Druyan, which is in a companion orbit with asteroid 2709 Sagan named after Druyan\'s late husband, is named after Druyan. In 2015, it was announced that Warner Brothers was in development on a drama about Sagan and Druyan\'s relationship, to be produced by producer Lynda Obst and Druyan. In 2020, Sagan and Druyan\'s daughter Sasha Sagan released a book For Small Creatures Such As We: Rituals for Finding Meaning in our Unlikely World, which discusses life with her parents and her father\'s death when she was fourteen years old. Druyan also gave Sasha a recurring role in Cosmos: Possible Worlds, where she played her own grandmother, including in the episode Man of a Trillion Worlds, which featured the life of Carl Sagan. ## Awards - 2004 Richard Dawkins Award - 2014 Outstanding Writing for Nonfiction Programming Primetime Emmy Award - 2015 The Award for Outstanding Producer of Non-Fiction Television from Producers Guild of America - 2015 Writers Guild Award for \"Documentary Script -- Other than Current Events\" - 2017 Harvard Humanist of the Year Award - 2020 National Geographic Further Award	2025-06-20T00:00:00
3,014	Analcime	Analcime (`{{IPAc-en\|ə\|ˈ\|n\|æ\|l\|s\|iː\|m\|,_\|-\|s\|aɪ\|m}}`{=mediawiki}; `{{etymology\|grc\|''{{wikt-lang\|grc\|ἀνάλκιμος}}'' ({{grc-transl\|ἀνάλκιμος}})\|not strong}}`{=mediawiki}) or analcite is a white, gray, or colorless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSi~2~O~6~ · H~2~O. Minor amounts of potassium and calcium substitute for sodium. A silver-bearing synthetic variety also exists (Ag-analcite). Analcime is usually classified as a zeolite mineral, but structurally and chemically it is more similar to the feldspathoids. Analcime is not classified as an isometric crystal, as although the crystal structure appears to be isometric, it is usually off only by a fraction of an angle. However, there are truly isometric samples of the mineral, which makes its classification even more difficult. Due to the differences between the samples being too slight, there\'s no merit from having multiple species names, so as a result analcime is a common example for minerals occurring in multiple crystal systems and space groups. It was first described by French geologist Déodat de Dolomieu, who called it zéolithe dure, meaning hard zeolite. It was found in lava in Cyclops, Italy. The mineral is IMA approved, and had been grandfathered, meaning the name analcime is believed to refer to a valid species til this day. ## Properties Analcime crystals always look pseudocubic. Its common crystal forms include trapezohedron, truncated trapezohedron with cubic faces, and more rarely either as a truncated trapezohedron, or the crystals can take the shape of a truncated cube that is typical to bixbyites. The crystals can occur either individually, as interconnected, form groups on plates or even in druzy form. Crystal masses can also form veins sometimes. Individual crystals are euhedral, meaning they have well defined faces. When on a matrix, the mineral takes a granular habit, meaning the crystals become anhedral. The color of the mineral varies due to trace impurities. The mineral is weakly piezoelectric and pyroelectric, meaning it produces a weak electric charge when it\'s rubbed or heated, hence the name analcime. Other characteristics include the fact that the mineral can have a blueish white fluorescence when inspected under short UV light, and a creamy white-yellow one inspected under long UV light. It does not show any pleochroic or radioactive properties. Analyses regarding the mineral\'s symmetry vary in results, however the most prevalent one being tetragonal. The mineral usually has polysynthetic twins, which are only visible in thin sections when the specimen is inspected under polarized analyzed light. Analcime mainly consists of oxygen (50.87%), silicon (25.51%), aluminum (12.26%), sodium (10.44%) but otherwise has a negligible amount of hydrogen (0.92%) as well. The highest quality specimens take the form of a trapezohedron, and can reach up to 25 cm. These specimens are associated with serandite, aegyrine and natrolite, and can be found at Mont Saint-Hilaire, Quebec. Of the pinkish-white specimens, the mineral takes the shape of well-formed cubes which can exceed 10 cm, originating from several sites in Val di Fassa, Trentino, Italy. ## Formation and associated minerals {#formation_and_associated_minerals} Analcime occurs as a primary mineral in analcime basalt and other alkaline igneous rocks. It also occurs as cavity and vesicle fillings associated with prehnite, calcite, and zeolites. Analcime forms in sedimentary rocks at temperatures below about 100 C, and so its presence indicates that the rock has experienced shallow diagenesis. Although it is common in igneous rocks (namely basalts and trachy-basalts), it is more rarely found in phonolites. Associations include zeolites, calcite and prehnite; however, it is also found in nepheline syenites and their pegmatites. It forms a series with pollucite. ## Locations Well known locations for sourcing analcime include Croft Quarry in Leicestershire, UK; the Cyclopean Islands east off Sicily and near Trentino in northern Italy; Victoria in Australia; Kerguelen Island in the Indian Ocean; in the Lake Superior copper district of Michigan, Bergen Hill, New Jersey, Golden, Colorado, and at Searles Lake, California in the United States; and at Cape Blomidon, Nova Scotia and Mont Saint-Hilaire, Quebec in Canada; and in Iceland, and in Namibia. Siberian samples from Nidym and Toura provide us with white crystals of 18 cm. Samples of the Cyclopean Islands are known for their beautiful and clear crystals, just like the crystals of Kings Valley and Springfield in Oregon, which can reach up to 6 cm. Coleman, Alberta in Canada is known for producing beautiful red crystals. ## Usage Other than its aesthetic values, analcime currently presents no use. Crystallized specimens are sought after by collectors, and the mineral is hardly ever made into jewelry. The crystals made into jewelries are uncut and handcrafted. It has lacking use as a microporous material. This is due to the fact that analcime has a compact structure and thus it has a strong resistance to diffusion of both molecules and cations. Analcime-bearing tuffs are sometimes used as building materials.	2025-06-20T00:00:00
3,019	ʻAbdu'l-Bahá	ʻAbdu\'l-Bahá `{{post-nominals\|country=GBR\|KBE}}`{=mediawiki} (`{{IPAc-en\|ə\|b\|ˈ\|d\|ʊ\|l\|_\|b\|ə\|ˈ\|h\|ɑː\|}}`{=mediawiki}; Persian: عبد البهاء, `{{IPA\|fa\|ʔæbdolbæhɒːʔ\|IPA}}`{=mediawiki};, 23 May 1844 -- 28 November 1921), born ʻAbbás (عباس, `{{IPA\|fa\|ʔæbːɒːs\|IPA}}`{=mediawiki}), was the eldest son of Baháʼu\'lláh, founder of the Bahá'í Faith, who designated him to be his successor and head of the Baháʼí Faith from 1892 until 1921. ʻAbdu\'l-Bahá was later cited as the last of three \"central figures\" of the religion, along with Baháʼu\'lláh and the Báb, and his writings and authenticated talks are regarded as sources of Baháʼí sacred literature. He was born in Tehran to an aristocratic family. At the age of eight, his father was imprisoned during a government crackdown on the Bábí Faith and the family\'s possessions were looted, leaving them in virtual poverty. His father was exiled from their native Iran, and the family established their residence in Baghdad in Iraq, where they stayed for ten years. They were later called by the Ottoman state to Istanbul before entering another period of confinement in Edirne and finally the prison-city of ʻAkká (Acre). ʻAbdu\'l-Bahá remained a prisoner there until the Young Turk Revolution freed him in 1908 at the age of 64. He then made several journeys to the West to spread the Baháʼí message beyond its middle-eastern roots, but the onset of World War I left him largely confined to Haifa from 1914 to 1918. Following the war, the openly hostile Ottoman authorities were replaced by the British Mandate over Palestine, during which time he was appointed a Knight Commander of the Order of the British Empire for his help in averting famine following the war. In 1892, ʻAbdu\'l-Bahá was appointed in his father\'s will to be his successor and head of the Baháʼí Faith. His Tablets of the Divine Plan galvanized Baháʼís in North America to spread the Baháʼí teachings to new territories, and his Will and Testament laid the foundation for the current Baháʼí administrative order. Many of his writings, prayers and letters are extant, and his discourses with the Western Baháʼís emphasize the growth of the religion by the late 1890s. ʻAbdu\'l-Bahá\'s given name was ʻAbbás. Depending on context, he would have gone by either Mírzá ʻAbbás (Persian) or ʻAbbás Effendi (Turkish), both of which are equivalent to the English Sir ʻAbbás. During most of his time as head of the Bahá\'í Faith, he used and preferred the title of ʻAbdu\'l-Bahá (\"servant of Bahá\", a reference to his father). He is commonly referred to in Baháʼí texts as \"The Master\". ## Early life {#early_life} ʻAbdu\'l-Bahá was born in Tehran, Persia (now Iran) on 23 May 1844 (5th of Jamadiyu\'l-Avval, 1260 AH), the eldest son of Baháʼu\'lláh and Navváb. He was born on the same night on which the Báb declared his mission. Given the name ʻAbbás at birth, he was named after his grandfather Mírzá ʻAbbás Núrí, a prominent and powerful nobleman. ʻAbdu\'l-Bahá\'s early years were shaped by his father\'s prominent role within the Bábí community. As a child, he fondly recalled interactions with the Bábí, Táhirih, describing how she would take him on her knee, caress him, and engage in heartfelt conversations, leaving a lasting impression on him. His childhood was characterized by happiness and carefree moments. The family\'s residences in Tehran and the countryside were not only comfortable but also beautifully adorned. Alongside his younger siblings -- a sister, Bahíyyih, and a brother, Mihdí -- he experienced a life of privilege, joy, and comfort. ʻAbdu\'l-Bahá loved playing in the gardens with his younger sister, fostering a strong bond between them. During his formative years, ʻAbdu\'l-Bahá observed his parents\' commitment to various charitable endeavors, including the conversion of part of their home into a hospital ward for women and children. Due to a life largely marked by exile and imprisonment, ʻAbdu\'l-Bahá had limited opportunities for formal schooling. In his youth, it was customary for children of nobility, including ʻAbdu\'l-Bahá, not to attend conventional schools. Instead, noblemen typically received a brief education at home, focusing on subjects such as scripture, rhetoric, calligraphy, and basic mathematics, with an emphasis on preparing for life within royal courts. ʻAbdu\'l-Bahá spent only a short period at a traditional preparatory school at the age of seven for a single year. His mother and uncle took on the responsibility of his early education, but the primary source of his learning was his father. In 1890 Edward Granville Browne described ʻAbdu\'l-Bahá, saying that \"one more eloquent of speech, more ready of argument, more apt of illustration, more intimately acquainted with the sacred books of the Jews, the Christians, and the Muhammadans\...could scarcely be found\...\" According to contemporary accounts ʻAbdu\'l-Bahá was an eloquent and charming child. At the age of seven, he faced a severe health challenge when he contracted tuberculosis, and his prognosis suggested death. Though the illness abated, this marked the beginning of a lifelong struggle with recurrent bouts of various illnesses that would persist throughout his life. One event that affected ʻAbdu\'l-Bahá greatly during his childhood was the imprisonment of his father when ʻAbdu\'l-Bahá was eight years old; this circumstance led to a considerable decline in the family\'s economic standing, subjecting him to poverty and exposing him to hostility from other children in the streets. ʻAbdu\'l-Bahá accompanied his mother to visit Baháʼu\'lláh who was then imprisoned in the infamous subterranean dungeon the Síyáh-Chál. He described how \"I saw a dark, steep place. We entered a small, narrow doorway, and went down two steps, but beyond those one could see nothing. In the middle of the stairway, all of a sudden we heard His \[Baháʼu\'lláh\'s\]...voice: \'Do not bring him in here\', and so they took me back\". ## Baghdad Baháʼu\'lláh was eventually released from prison but was ordered into exile, and ʻAbdu\'l-Bahá, then eight years old, joined his father on the journey to Baghdad in the winter (January to April) of 1853. During the journey ʻAbdu\'l-Bahá suffered from frost-bite. After a year of difficulties, Baháʼu\'lláh absented himself rather than continuing to face the conflict with Mirza Yahya and secluded himself in the mountains of Sulaymaniyah in April 1854, a month before ʻAbdu\'l-Bahá\'s tenth birthday Due to mutual sorrow, ʻAbdu\'l-Bahá, his mother and sister becoming constant companions. ʻAbdu\'l-Bahá was particularly close to both, and his mother took an active role in his education and upbringing. During the two-year absence of his father ʻAbdu\'l-Bahá took up the duty of managing the affairs of the family, before his age of maturity (14 in Middle-Eastern society) and was known to be occupied with reading and, at a time of hand-copied scriptures being the primary means of publishing, was also engaged in copying the writings of the Báb. ʻAbdu\'l-Bahá also took an interest in the art of horseback riding, and as he grew, he became a renowned rider. In 1856, news of an ascetic engaging in discourses with local Súfí leaders reached family and friends, raising hopes that it could be Bahá'u'lláh. Immediately, they went to search for Baháʼu\'lláh, and in March, brought him back to Baghdad. On seeing his father, ʻAbdu\'l-Bahá fell to his knees and wept loudly \"Why did you leave us?\", and his mother and sister did the same. ʻAbdu\'l-Bahá soon became his father\'s secretary and shield. During the sojourn in the city ʻAbdu\'l-Bahá grew from a boy into a young man. He was noted as a \"remarkably fine looking youth\", and remembered for his charity. Having passed the age of maturity, ʻAbdu\'l-Bahá was regularly seen in the mosques of Baghdad discussing religious topics and the scripture as a young man. Whilst in Baghdad, ʻAbdu\'l-Bahá composed a commentary at the request of his father on the Muslim tradition of \"I was a Hidden Treasure\" for a Súfí leader named ʻAlí Shawkat Páshá. ʻAbdu\'l-Bahá was fifteen or sixteen at the time and ʻAlí Shawkat Páshá regarded the more than 11,000-word essay as a remarkable feat for someone of his age. In 1863, in what became known as the Garden of Ridván, his father Baháʼu\'lláh announced to a few companions that he was the manifestation of God and He whom God shall make manifest whose coming had been foretold by the Báb. On day eight of the twelve days, it is reported that ʻAbdu\'l-Bahá was the first person to whom Baháʼu\'lláh revealed his claim. ## Istanbul/Adrianople In 1863, Baháʼu\'lláh was summoned to Istanbul, and thus his family, including ʻAbdu\'l-Bahá, then eighteen, accompanied him on his 110-day journey. The journey to Constantinople was another wearisome voyage, and ʻAbdu\'l-Bahá helped feed the exiles. It was here that his position became more prominent amongst the Baháʼís. This was further solidified by Baháʼu\'lláh\'s tablet of the Branch in which he constantly exalts his son\'s virtues and station. Bahá'u'lláh and his family were soon exiled to Adrianople, and on this journey ʻAbdu\'l-Bahá again suffered from frostbite. In Adrianople ʻAbdu\'l-Bahá was regarded as the sole comforter of his family -- in particular to his mother. At this point ʻAbdu\'l-Bahá was known by the Baháʼís as \"the Master\", and by non-Baháʼís as ʻAbbás Effendi (\"Effendi\" signifies \"Sir\"). It was in Adrianople that Baháʼu\'lláh referred to his son as \"the Mystery of God\". The title of \"Mystery of God\" symbolises, according to Baháʼís, that ʻAbdu\'l-Bahá is not a manifestation of God but that in the \"person of ʻAbdu\'l-Bahá the incompatible characteristics of a human nature and superhuman knowledge and perfection have been blended and are completely harmonized\". Baháʼu\'lláh gave his son many other titles such as G͟husn-i-Aʻzam (meaning \"Mightiest Branch\" or \"Mightier Branch\"), the \"Branch of Holiness\", \"the Center of the Covenant\" and the apple of his eye. Upon learning of yet another exile of Bahá'u'llah, this time to Palestine, ʻAbdu\'l-Bahá (\"the Master\") was devastated when hearing the news that he and his family were to be exiled separately from Baháʼu\'lláh. It was, according to Baháʼís, through his intercession that the idea was reverted and the rest of the family were allowed to be exiled together. ## ʻAkká At the age of 24, ʻAbdu\'l-Bahá was clearly chief-steward to his father and an outstanding member of the Baháʼí community. In 1868 Baháʼu\'lláh and his family were exiled to the penal colony of ʻAkká, Palestine where it was expected that the family would perish. Arrival in ʻAkká was distressing for the family and exiles when they were met by a hostile local population. When told that the women were to sit on the shoulders of the men to reach the shore, ʻAbdu\'l-Bahá obtained chairs to carry the women to land. His sister and father fell dangerously ill. ʻAbdu\'l-Bahá was able to procure some anesthetic and nursed the sick. The Baháʼís were imprisoned under horrendous conditions in a cluster of cells covered in excrement and dirt. ʻAbdu\'l-Bahá himself fell dangerously ill with dysentery, and a sympathetic soldier permitted a physician to attend to him. The population shunned them, the soldiers treated them badly, and the behaviour of Siyyid Muhammad-i-Isfahani (an Azali) aggravated matters. Morale declined further with the accidental death of ʻAbdu\'l-Bahá\'s youngest brother Mírzá Mihdí at the age of 22. The grieving ʻAbdu\'l-Bahá kept a night-long vigil beside his brother\'s body. ### Later in ʻAkká {#later_in_ʻakká} Over time, he gradually assumed responsibility for the relationships between the small Baháʼí exile community and the outside world. It was through his interaction with the people of ʻAkká (Acre) that, they recognized the innocence of the Baháʼís, and thus the conditions of imprisonment were eased. Four months after the death of Mihdí the family moved from the prison to the House of ʻAbbúd. Gradually the respect of the local population for the Baháʼís increased, and in particular, for ʻAbdu\'l-Bahá who soon became very popular in the penal colony. Myron Henry Phelps a wealthy New York lawyer described how \"a crowd of human beings\...Syrians, Arabs, Ethiopians, and many others\", all waited to talk and receive ʻAbdu\'l-Bahá. With the passage of time ʻAbdu\'l-Bahá was able to rent alternative accommodations for the family, and eventually the family moved to the Mansion of Bahjí around 1879 when an epidemic caused its residents to flee. ʻAbdu\'l-Bahá undertook a history of the Bábí religion through publication of A Traveller\'s Narrative (Makála-i-Shakhsí Sayyáh) in 1886, later translated and published in translation in 1891 through Cambridge University through the agency of Edward Granville Browne. ### Marriage and family life {#marriage_and_family_life} When ʻAbdu\'l-Bahá was a young man, speculation was rife amongst the Baháʼís as to whom he would marry. Several young girls were seen as marriage prospects but ʻAbdu\'l-Bahá seemed disinclined to marriage. On 8 March 1873, at the urging of his father, the twenty-eight-year-old ʻAbdu\'l-Bahá married Fátimih Nahrí of Isfahán (1847--1938) a twenty-five-year-old from an upper-class family of the city. Her father was Mírzá Muḥammad ʻAlí Nahrí of Isfahan, an eminent Baháʼí with prominent connections. Fátimih was brought from Persia to ʻAkká after both Baháʼu\'lláh and his wife Navváb expressed an interest that she marries ʻAbdu\'l-Bahá. After a wearisome journey from Isfahán to Akka she finally arrived accompanied by her brother in 1872. The young couple were betrothed for about five months before the marriage itself commenced. In the meantime, Fátimih lived in the home of ʻAbdu\'l-Bahá\'s uncle Mírzá Músá. According to her later memoirs, Fátimih fell in love with ʻAbdu\'l-Bahá on seeing him. ʻAbdu\'l-Bahá himself had shown little inkling to marriage until meeting Fátimih; who was entitled Munírih by Baháʼu\'lláh. Munírih is a title meaning \"Luminous\". The marriage resulted in nine children. The first born was a son Mihdí Effendi who died aged about 3. He was followed by Ḍíyáʼíyyih K͟hánum, Fuʼádíyyih K͟hánum (who dies very young), Rúhangíz Khánum (d. 1893), Túbá Khánum, Husayn Effendi (d. 1887 aged 5), Túbá K͟hánum, Rúhá K͟hánum (mother of Munib Shahid), and Munnavar K͟hánum. The death of his children caused ʻAbdu\'l-Bahá immense grief -- in particular the death of his son Husayn Effendi came at a difficult time following the death of his mother and uncle. The surviving children (all daughters) were; Ḍíyáʼíyyih K͟hánum (mother of Shoghi Effendi) (d. 1951) Túbá K͟hánum (1880--1959) Rúḥá K͟hánum and Munavvar K͟hánum (d. 1971). Baháʼu\'lláh wished that the Baháʼís follow the example of ʻAbdu\'l-Bahá and gradually move away from polygamy. The marriage of ʻAbdu\'l-Bahá to one woman and his choice to remain monogamous, from advice of his father and his own wish, legitimised the practice of monogamy to a people who hitherto had regarded polygamy as a righteous way of life. ## Early years of his ministry {#early_years_of_his_ministry} After Baháʼu\'lláh died on 29 May 1892, the Book of the Covenant of Baháʼu\'lláh (his will) named ʻAbdu\'l-Bahá as Centre of the Covenant, successor and interpreter of Baháʼu\'lláh\'s writings. Baháʼu\'lláh designates his successor with the following verses: `{{blockquote\|The Will of the divine Testator is this: It is incumbent upon the [[Aghsán]], the [[Afnán]] and [[Baháʼu'lláh's family\|My Kindred]] to turn, one and all, their faces towards the Most Mighty Branch. Consider that which We have revealed in Our Most Holy Book: 'When the ocean of My presence hath ebbed and the Book of My Revelation is ended, turn your faces toward Him Whom God hath purposed, Who hath branched from this Ancient Root.' The object of this sacred verse is none other except the Most Mighty Branch [ʻAbdu'l-Bahá]. Thus have We graciously revealed unto you Our potent Will, and I am verily the Gracious, the All-Powerful. Verily God hath ordained the station of the Greater Branch [Muḥammad ʻAlí] to be beneath that of the Most Great Branch [ʻAbdu'l-Bahá]. He is in truth the Ordainer, the All-Wise. We have chosen 'the Greater' after 'the Most Great', as decreed by Him Who is the All-Knowing, the All-Informed.\|{{harvtxt\|Baháʼu'lláh\|1873–1892}} }}`{=mediawiki} In Baháʼu\'lláh\'s will, ʻAbdu\'l-Bahá\'s half-brother, Muhammad ʻAlí, was mentioned by name as being subordinate to ʻAbdu\'l-Bahá. Muhammad ʻAlí became jealous of 'Abdu'l-Bahá and set out to establish authority for himself as an alternative leader with the support of his brothers Badi'u\'llah and Ḍíyáʼu\'llah. He began correspondence with Baháʼís in Iran, initially in secret, casting doubts in others\' minds about ʻAbdu\'l-Bahá. While most Baháʼís followed ʻAbdu\'l-Bahá, a handful followed Muhammad ʻAlí including such prominent Bahá'ís as Mirza Javad and Ibrahim George Kheiralla, an early Baháʼí missionary to America. Muhammad ʻAlí and Mirza Javad began to openly accuse ʻAbdu\'l-Bahá of assuming too much authority, suggesting that he believed himself to be a Manifestation of God, equal in status to Baháʼu\'lláh. It was at this time that ʻAbdu\'l-Bahá, to counter the accusations leveled against him, stated in tablets to the West that he was to be known as \"ʻAbdu\'l-Bahá\" an Arabic phrase meaning the Servant of Bahá to make it clear that he was not a Manifestation of God, and that his station was only servitude. ʻAbdu\'l-Bahá left a Will and Testament that established the framework of the administration of the Baháʼí Faith, the two highest institutions of which were the Universal House of Justice, and the Guardianship, for which he appointed his grandson Shoghi Effendi as the Guardian. With the exception of ʻAbdu\'l-Bahá and Shoghi Effendi, Muhammad ʻAlí was supported by all of the remaining male relatives of Baháʼu\'lláh, including Shoghi Effendi\'s father, Mírzá Hádí Shírází. However, in general the Bahá'ís experienced very little effect from the propaganda of Muhammad ʻAlí and his allies; in the ʻAkká area, the followers of Muhammad ʻAlí represented six families at most, had no common religious activities, and were almost wholly assimilated into Muslim society. Religions in the past faced schism and doctrinal drift after the death of their prophet founders. ʻAbdu\'l-Bahá however managed to preserve the unity and doctrinal integrity of the Baháʼí Faith, even in the face of serious threats from his half-brother\'s opposition. His success is especially notable given that even in the midst of these attacks his leadership brought about considerable expansion of the Baháʼí community beyond its initial cultural and geographic roots. ### First Western pilgrims {#first_western_pilgrims} By the end of 1898, Western pilgrims started traveling to Akka on pilgrimage to visit ʻAbdu\'l-Bahá; this group of pilgrims, including Phoebe Hearst, was the first time that Baháʼís raised up in the West had met ʻAbdu\'l-Bahá. The first group arrived in 1898 and throughout late 1898 to early 1899 Western Baháʼís sporadically visited ʻAbdu\'l-Bahá. The group was relatively young containing mainly women from high American society in their 20s. The group of Westerners aroused suspicion for the authorities, and consequently ʻAbdu\'l-Bahá\'s confinement was tightened. During the next decade ʻAbdu\'l-Bahá would be in constant communication with Baháʼís around the world, encouraging them to teach the religion; the group included Susan Moody, Lua Getsinger, Laura Clifford Barney, Herbert Hopper and May Ellis Bolles in Paris (all Americans); Englishman Thomas Breakwell; and Frenchman `{{Interlanguage link\|Hippolyte Dreyfus\|fr\|3=Hippolyte Dreyfus-Barney}}`{=mediawiki}. It was Laura Clifford Barney who, by asking questions of ʻAbdu\'l-Bahá over many years and many visits to Haifa, compiled what later became the book Some Answered Questions. ### Ministry, 1901--1912 {#ministry_19011912} During the final years of the 19th century, while ʻAbdu\'l-Bahá was still officially a prisoner and confined to ʻAkka, he organized the transfer of the remains of the Báb from Iran to Palestine. He then organized the purchase of land on Mount Carmel that Baháʼu\'lláh had instructed should be used to lay the remains of the Báb, and organized for the construction of the Shrine of the Báb. This process took another 10 years. With the increase of pilgrims visiting ʻAbdu\'l-Bahá, Muhammad ʻAlí conspired with the Ottoman authorities to re-introduce stricter terms on ʻAbdu\'l-Bahá\'s imprisonment in August 1901. By 1902, however, due to the support of the Governor of ʻAkka, the situation was greatly eased; while pilgrims were able to once again visit ʻAbdu\'l-Bahá, he was still confined to the city. In February 1903, two followers of Muhammad ʻAlí, including Badiʻu\'llah and Siyyid ʻAliy-i-Afnan, broke with Muhammad ʻAli and wrote books and letters giving details of Muhammad ʻAli\'s plots and noting that what was circulating about ʻAbdu\'l-Bahá was fabrication. From 1902 to 1904, even as 'Abdu'l-Bahá directed the construction of the Shrine of the Báb, he initiated execution of two additional projects; the restoration of the House of the Báb in Shiraz, Iran and the construction of the first Baháʼí House of Worship in Ashgabat, Turkmenistan. ʻAbdu\'l-Bahá asked Aqa Mirza Aqa to coordinate the restoration of the house of the Báb to its state at the time of the Báb\'s declaration to Mulla Husayn in 1844; he also entrusted the work on the House of Worship to Vakil-u\'d-Dawlih. In his role as head of the Bahá'í Faith, 'Abdu'l-Bahá would occasionally communicate with leaders of thought to offer commentary and guidance based on the Bahá'í teachings, and in defense of the Bahá'í community. During this period, ʻAbdu\'l-Bahá communicated with a number of Young Turks, who sought to reform to the reign of Sultan Abdul Hamid II, including Namık Kemal, Ziya Pasha and Midhat Pasha. He emphasized Baháʼís \"seek freedom and love liberty, hope for equality, are well-wishers of humanity and ready to sacrifice their lives to unite humanity\" but on a more broad approach than the Young Turks. Abdullah Cevdet, one of the founders of the Committee of Union and Progress who considered the Baháʼí Faith an intermediary step between Islam and the ultimate abandonment of religious belief, would go on trial for defense of Baháʼís in a periodical he founded. ‛Abdu\'l-Bahá also had contact with military leaders, including such individuals as Bursalı Mehmet Tahir Bey and Hasan Bedreddin. The latter, who in an earlier period was involved in the overthrow of Sultan Abdülaziz in 1876, is commonly known as Bedri Paşa or Bedri Pasha and is referred to in Persian Baháʼí sources as Bedri Bey (Badri Beg). He probably came to know 'Abdu'l-Baha around 1898 when he served in the Ottoman administration in Akká. Persian sources cite him was a Baháʼí and he who translated ‛Abdu\'l-Baha\'s works into French. 'Abdu'l-Bahá continued to communicate with him for several years when he was governor of Albania. ʻAbdu\'l-Bahá also met Muhammad Abduh, one of the key figures of Islamic Modernism and the Salafi movement, in Beirut, at a time when the two men shared similar goals of religious reform. Rashid Rida asserts that during his visits to Beirut, ʻAbdu\'l-Bahá would attend Abduh\'s study sessions. Regarding the meetings of ʻAbdu\'l-Bahá and Muhammad ʻAbduh, Shoghi Effendi asserts that \"His several interviews with the well-known Shaykh Muhammad ʻAbdu served to enhance immensely the growing prestige of the community and spread abroad the fame of its most distinguished member.\" Due to Muhammad ʻAli\'s accusations against him, a Commission of Inquiry interviewed ʻAbdu\'l-Bahá in 1905, almost resulting in exile to Fezzan. In response, ʻAbdu\'l-Bahá wrote the sultan a letter protesting that his followers refrain from involvement in partisan politics and that his tariqa had guided many Americans to Islam. The next few years in ʻAkka were relatively free of pressures and pilgrims were able to come and visit ʻAbdu\'l-Bahá. By 1909 the mausoleum of the Shrine of the Báb was completed. ## Journeys to the West {#journeys_to_the_west} The 1908 Young Turks revolution liberated all political and religious prisoners in the Ottoman Empire, and ʻAbdu\'l-Bahá was freed from imprisonment. His first action after his liberation was to visit the Shrine of Baháʼu\'lláh in Bahji. While ʻAbdu\'l-Bahá continued to live in ʻAkka immediately following the revolution, he soon moved to live in Haifa near the Shrine of the Báb. In 1910, with the freedom to leave the country, he embarked on a three-year journey to Egypt, Europe, and North America, spreading the Baháʼí message. From August to December 1911, ʻAbdu\'l-Bahá visited cities in Europe, including London, Bristol, and Paris. The purpose of these trips was to support the Baháʼí communities in the west and to further spread his father\'s teachings. In the following year, he undertook a much more extensive journey to the United States and Canada to once again spread his father\'s teachings. He arrived in New York City on 11 April 1912, after declining an offer of passage on the RMS Titanic, telling the Baháʼí believers, instead, to \"Donate this to charity.\" He instead travelled on a slower craft, the RMS Cedric, and cited preference of a longer sea journey as the reason. After hearing of the Titanic\'s sinking on 16 April he was quoted as saying \"I was asked to sail upon the Titanic, but my heart did not prompt me to do so.\" While he spent most of his time in New York, he visited Chicago, Cleveland, Pittsburgh, Washington, D.C.,Boston and Philadelphia. In August of the same year he started a more extensive journey to places including New Hampshire, the Green Acre school in Maine, and Montreal (his only visit to Canada). He then travelled west to Minneapolis, Minnesota; San Francisco; Stanford; and Los Angeles, California before returning east at the end of October. On 5 December 1912 he set sail back to Europe. During his visit to North America he visited many missions, churches, and groups, as well as having scores of meetings in homes of Baháʼís, and offering innumerable personal meetings with hundreds of people. During his talks he proclaimed Baháʼí principles such as the unity of God, unity of the religions, oneness of humanity, equality of women and men, world peace and economic justice. He also insisted that all his meetings be open to all races. His visit and talks were the subject of hundreds of newspaper articles. In Boston newspaper reporters asked ʻAbdu\'l-Bahá why he had come to America, and he stated that he had come to participate in conferences on peace and that just giving warning messages is not enough. ʻAbdu\'l-Bahá\'s visit to Montreal provided notable newspaper coverage; on the night of his arrival the editor of the Montreal Daily Star met with him and that newspaper along with The Montreal Gazette, Montreal Standard, \[\[Le Devoir\]\] and La Presse\]\] among others reported on ʻAbdu\'l-Bahá\'s activities. The headlines in those papers included \"Persian Teacher to Preach Peace\", \"Racialism Wrong, Says Eastern Sage, Strife and War Caused by Religious and National Prejudices\", and \"Apostle of Peace Meets Socialists, Abdul Baha\'s Novel Scheme for Distribution of Surplus Wealth.\" The Montreal Standard, which was distributed across Canada, took so much interest that it republished the articles a week later; the Gazette published six articles and Montreal\'s largest French language newspaper published two articles about him. His 1912 visit to Montreal also inspired humourist Stephen Leacock to parody him in his bestselling 1914 book Arcadian Adventures with the Idle Rich. In Chicago one newspaper headline included \"His Holiness Visits Us, Not Pius X but A. Baha,\" and ʻAbdu\'l-Bahá\'s visit to California was reported in the Palo Altan. Back in Europe, he visited London, Edinburgh, Paris (where he stayed for two months), Stuttgart, Budapest, and Vienna. Finally, on 12 June 1913, he returned to Egypt, where he stayed for six months before returning to Haifa. On 23 February 1914, at the eve of World War I, ʻAbdu\'l-Bahá hosted Baron Edmond James de Rothschild, a member of the Rothschild banking family who was a leading advocate and financier of the Zionist movement, during one of his early trips to Palestine. ## Final years (1914--1921) {#final_years_19141921} thumb\\|upright=1.25\\|ʻAbdu\'l-Bahá on Mount Carmel with pilgrims in 1919 During World War I (1914--1918) ʻAbdu\'l-Bahá stayed in Palestine and was unable to travel. He carried on a limited correspondence, which included the Tablets of the Divine Plan, a collection of fourteen letters addressed to the Baháʼís of North America, later described as one of three \"charters\" of the Baháʼí Faith. The letters assign a leadership role for the North American Baháʼís in spreading the religion around the planet. Haifa was under real threat of Allied bombardment, enough that ʻAbdu\'l-Bahá and other Baháʼís temporarily retreated to the hills east of ʻAkka. ʻAbdu\'l-Bahá was also under threats from Cemal Paşa, the Ottoman military chief who at one point expressed his desire to crucify him and destroy Baháʼí properties in Palestine. The swift Megiddo offensive of the British General Allenby swept away the Turkish forces in Palestine before harm was done to the Baháʼís, and the war was over less than two months later. ### Post-war period {#post_war_period} The conclusion of World War I led to the openly hostile Ottoman authorities being replaced by the more friendly British Mandate, allowing for a renewal of correspondence, pilgrims, and development of the Baháʼí World Centre properties. It was during this revival of activity that the Baháʼí Faith saw an expansion and consolidation in places like Egypt, the Caucasus, Iran, Turkmenistan, North America and South Asia under the leadership of ʻAbdu\'l-Bahá. The end of the war brought about several political developments on which ʻAbdu\'l-Bahá commented. The League of Nations formed in January 1920, representing the first instance of collective security through a worldwide organization. ʻAbdu\'l-Bahá had written in 1875 for the need to establish a \"Union of the nations of the world\", and he praised the attempt through the League of Nations as an important step towards the goal. He also said that it was \"incapable of establishing Universal Peace\" because it did not represent all nations and had only trivial power over its member states. Around the same time, the British Mandate supported the ongoing immigration of Jews to Palestine. ʻAbdu\'l-Bahá mentioned the immigration as a fulfillment of prophecy, and encouraged the Zionists to develop the land and \"elevate the country for all its inhabitants\... They must not work to separate the Jews from the other Palestinians\...If the Zionists will mingle with the other races and live in unity with them, they will succeed. If not, they will meet certain resistance.\" thumb\\|upright=1.25\\|ʻAbdu\'l-Bahá at his investiture ceremony as a Knight Commander of the Order of the British Empire, April 1920 The war also left the region in famine. In 1901, ʻAbdu\'l-Bahá had purchased about 1704 acres of scrubland near the Jordan river and by 1907 many Baháʼís from Iran had begun sharecropping on the land. ʻAbdu\'l-Bahá received between 20 and 33% of their harvest (or cash equivalent), which was shipped to Haifa. With the war still raging in 1917, ʻAbdu\'l-Bahá received a large amount of wheat from the crops, and also bought other available wheat and shipped it back to Haifa. The wheat arrived just after the British captured Palestine, and as such was widely distributed to allay the famine. For this service in averting a famine in Northern Palestine he received the honour of Knight Commander of the Order of the British Empire at a ceremony held in his honor at the home of the British Governor on 27 April 1920. He was later visited by General Allenby, King Faisal (later King of Iraq), Herbert Samuel (High Commissioner for Palestine), and Ronald Storrs (Military Governor of Jerusalem). ### Death and funeral {#death_and_funeral} thumb\\|upright=1.25\\|Funeral of ʻAbdu\'l-Bahá in Haifa, British Mandate-Palestine ʻAbdu\'l-Bahá died on Monday, 28 November 1921, sometime after 1:15 a.m. (27th of Rabi\' al-awwal, 1340 AH). Then Colonial Secretary Winston Churchill telegraphed the High Commissioner for Palestine, \"convey to the Baháʼí Community, on behalf of His Majesty\'s Government, their sympathy and condolence.\" Similar messages came from Viscount Allenby, the Council of Ministers of Iraq, and others. On his funeral, which was held the next day, Esslemont notes: `{{blockquote\|text=... a funeral the like of which Haifa, nay Palestine itself, had surely never seen... so deep was the feeling that brought so many thousands of mourners together, representative of so many religions, races and tongues.<ref>{{harvnb\|Esslemont\|1980\|p=77}}, quoting 'The Passing of ʻAbdu'l-Bahá", by Lady Blomfield and Shoghi Effendi, pp 11, 12.</ref>}}`{=mediawiki} Among the talks delivered at the funeral, Shoghi Effendi records Stewart Symes (Governor of the Palestine North District) giving the following tribute: He was buried in the front room of the Shrine of the Báb on Mount Carmel. His interment there is meant to be temporary, until his own mausoleum can be built in the vicinity of Riḍván Garden, known as the Shrine of ʻAbdu\'l-Bahá. ### Legacy ʻAbdu\'l-Bahá left a Will and Testament that was originally written between 1901 and 1908 and addressed to Shoghi Effendi, who at that time was only 4--11 years old. The will appoints Shoghi Effendi as the first in a line of Guardians of the religion, a hereditary executive role that may provide authoritative interpretations of scripture. ʻAbdu\'l-Bahá directed all Baháʼís to turn to him and obey him, and assured him of divine protection and guidance. The will also provided a formal reiteration of his teachings, such as the instructions to teach, manifest spiritual qualities, associate with all people, and shun Covenant-breakers. Many obligations of the Universal House of Justice and the Hands of the Cause were also elaborated. Shoghi Effendi later described the document as one of three \"charters\" of the Baháʼí Faith. The authenticity and provisions of the will were almost universally accepted by Baháʼís around the world, with the exception of Ruth White and a few other Americans who tried to protest Shoghi Effendi\'s leadership. In volumes of The Baháʼí World published in 1930 and 1933, Shoghi Effendi named nineteen Baháʼís as disciples of ʻAbdu\'l-Bahá and heralds of the Covenant, including Thornton Chase, `{{Interlanguage link\|Hippolyte Dreyfus-Barney\|fr}}`{=mediawiki}, John Esslemont, Lua Getsinger, and Robert Turner. No other statements about them have been found in Shoghi Effendi\'s writings. During his lifetime there was some ambiguity among Baháʼís as to his station relative to Baháʼu\'lláh, and later to Shoghi Effendi. Some American newspapers erroneously reported him to be a Baháʼí prophet or the return of Christ. Shoghi Effendi later formalized his legacy as the last of three \"Central Figures\" of the Baháʼí Faith and the \"Perfect exemplar\" of the teachings, also claiming that holding him on an equal status to Baháʼu\'lláh or Jesus was heretical. Shoghi Effendi also wrote that during the anticipated Baháʼí dispensation of 1000 years there will be no equal to ʻAbdu\'l-Bahá. ## Appearance and personality {#appearance_and_personality} ʻAbdu\'l-Bahá was described as handsome, and bore striking resemblance to his mother. As an adult he reached medium height but he gave the impression of being taller. He had dark hair that flowed to his shoulders, grey coloured eyes, a fair complexion and an aquiline nose. In 1890, Orientalist Edward Granville Browne met him and wrote: After the death of Bahá'u'lláh, ʻAbdu\'l-Bahá began to visibly age. By the late 1890s his hair had turned snow-white and deep lines set on his face. As a young man he was athletic and enjoyed archery, horseback riding and swimming. Even later in his life ʻAbdu\'l-Bahá remained active going for long walks in Haifa and Acre. ʻAbdu\'l-Bahá was a major presence for the Bahá'ís during his lifetime, and he continues to influence the Bahá'í community today. Bahá'ís regard 'Abdu'l-Bahá as the perfect example of the teachings of his father and therefore strive to emulate him. Anecdotes about him are frequently used to illustrate particular points about morality and interpersonal relations. He was remembered for his charisma, compassion, philanthropy and strength in the face of suffering. John Esslemont reflected that \"\['Abdu'l-Bahá\] showed that it is still possible, amid the whirl and rush of modern life, amid the self-love and struggle for material prosperity that everywhere prevail, to live the life of entire devotion to God and to the service of one\'s fellows.\" Even ardent enemies of the Bahá'í Faith were on occasion taken by meeting him. Mírzá \'Abdu\'l-Muḥammad Írání Mu\'addibu\'s-Sulṭán, an Iranian, and Shaykh \'Alí Yúsuf, an Arab, were both newspaper editors in Egypt who had published harsh attacks on the Bahá'í Faith in their papers. They called on 'Abdu'l-Bahá when he was in Egypt and their attitude changed. Similarly, a Christian clergyman, Rev. J.T. Bixby, who was the author of a hostile article on the Bahá'í Faith in the United States, felt compelled to witness Abdu\'l-Bahá\'s personal qualities. The effect of 'Abdu'l-Bahá on those who were already committed Bahá'ís was greater still. ʻAbdu\'l-Bahá was widely known for his encounters with the poor and dying. His generosity resulted in his own family complaining that they were left with nothing. He was sensitive to people's feelings, and later expressed his wish to be a beloved figure of the Bahá'ís saying "I am your father\...and you must be glad and rejoice, for I love you exceedingly." According to historical accounts, he had a keen sense of humour and was relaxed and informal. He was open about personal tragedies such as the loss of his children and the sufferings he\'d endured as a prisoner, further enhancing his popularity. 'Abdu'l-Bahá directed the affairs of the Bahá'í community with care. He was inclined to allow a large range of personal interpretations of the Bahá'í teachings as long as these did not obviously contradict fundamental principles. He did, however, expel members of the religion he felt were challenging his leadership and deliberately causing disunity in the community. Outbreaks of persecution of the Bahá'ís affected him deeply. He wrote personally to the families of those who had been martyred. ## Works The total estimated number of tablets that ʻAbdu\'l-Bahá wrote are over 27,000 of which only a fraction have been translated into English. His works fall into two groups including first his direct writings and second his lectures and speeches as noted by others. The first group includes The Secret of Divine Civilization written before 1875, A Traveller\'s Narrative written around 1886, the Resāla-ye sīāsīya or Sermon on the Art of Governance written in 1893, the Memorials of the Faithful, and a large number of tablets written to various people; including various Western intellectuals such as Auguste Forel which has been translated and published as the Tablet to Auguste-Henri Forel. The Secret of Divine Civilization and the Sermon on the Art of Governance were widely circulated anonymously. The second group includes Some Answered Questions, which is an English translation of a series of table talks with Laura Barney, and Paris Talks, ʻAbdu\'l-Baha in London and Promulgation of Universal Peace which are respectively addresses given by ʻAbdu\'l-Bahá in Paris, London and the United States. The following is a list of some of ʻAbdu\'l-Bahá\'s many books, tablets, and talks: - Foundations of World Unity - [Light of the World: Selected Tablets of 'Abdu'l-Bahá](https://www.bahai.org/library/authoritative-texts/abdul-baha/light-of-the-world). - Memorials of the Faithful - Paris Talks - Secret of Divine Civilization - Some Answered Questions - Tablets of the Divine Plan - Tablet to Auguste-Henri Forel - Tablet to The Hague - Will and Testament of ʻAbdu\'l-Bahá - Promulgation of Universal Peace - Selections from the Writings of ʻAbdu\'l-Bahá - Divine Philosophy - Treatise on Politics / Sermon on the Art of Governance	2025-06-20T00:00:00
3,020	Ambrose of Alexandria	Ambrose of Alexandria (before 212 -- c. 250) was a friend of the Christian theologian Origen. ## Life Ambrose was attracted by Origen\'s fame as a teacher, and visited the Catechetical School of Alexandria in 212. At first a gnostic Valentinian and Marcionist, Ambrose, through Origen\'s teaching, eventually rejected this theology and became Origen\'s constant companion, and was ordained deacon. He plied Origen with questions, and urged him to write his Commentaries (treating him as \"ἐργοδιώκτης\" in Commentary on John V,1) on the books of the Bible, and, as a wealthy nobleman and courtier, he provided his teacher with books for his studies and secretaries to lighten the labor of composition. He suffered during the persecution under the Roman emperor Maximinus Thrax in 235. He was later released and died a confessor. The last mention of Ambrose in the historical record is in Origen\'s Contra Celsum, which the latter wrote at the solicitation of Ambrose. Origen often speaks of Ambrose affectionately as a man of education with excellent literary and scholarly tastes. All of Origen\'s works written after 218 are dedicated to Ambrose, including his On Martyrdom, Contra Celsum, Commentary on St. John\'s Gospel, and On Prayer. Ambrose\'s letters to Origen (praised by Jerome) are lost, although part of one exists. ## Veneration Ambrose is venerated as a saint by some branches of Christianity. His feast day in the Catholic Church falls on 17 March.	2025-06-20T00:00:00
3,022	Autonomous building	An autonomous building is a hypothetical building designed to be operated independently from infrastructural support services such as the electric power grid, gas grid, municipal water systems, sewage treatment systems, storm drains, communication services, and in some cases, public roads. The literature mostly refers to housing, or the autonomous house. Advocates of autonomous building describe advantages that include reduced environmental impacts, increased security, and lower costs of ownership. Some cited advantages satisfy tenets of green building, not independence per se (see below). Off-grid buildings often rely very little on civil services and are therefore safer and more comfortable during civil disaster or military attacks. For example, off-grid buildings would not lose power or water if public supplies were compromised. ## History ### 1970s In the 1970s, groups of activists and engineers were inspired by the warnings of imminent resource depletion and starvation. In the United States, a group calling themselves the New Alchemists were famous for the depth of research effort placed in their projects. Using conventional construction techniques, they designed a series of \"bioshelter\" projects, the most famous of which was The Ark bioshelter community for Prince Edward Island. They published the plans for all of these, with detailed design calculations and blueprints. The Ark used wind-based water pumping and electricity and was self-contained in food production. It had living quarters for people, fish tanks raising tilapia for protein, a greenhouse watered with fish water, and a closed-loop sewage reclamation system that recycled human waste into sanitized fertilizer for the fish tanks. Around 1975--1977, Australian architect and lecturer at University of Sydney School of Architecture, Col James, in collaboration with urban designer, architect, artist, and university tutor Nick Hollo, designed and built an autonomous house on university grounds, in collaboration with students. This taught self-build sustainability to hundreds of students. ### 1990s {#s_1} The 1990s saw the development of Earthships, similar in intent to the Ark project, but organised as a for-profit venture, with construction details published in a series of three books by American architect Mike Reynolds. The building material is tires filled with earth. This makes a wall that has large amounts of thermal mass (see earth sheltering). Berms are placed on exposed surfaces to further increase the house\'s temperature stability. The water system starts with rain water, processed for drinking, then washing, then plant watering, then toilet flushing, and finally black water is recycled again for more plant watering. The cisterns are placed and used as thermal masses. Power, including electricity, heat and water heating, is from solar power. Some 1990s architects such as William McDonough and Ken Yeang applied environmentally responsible building design to large commercial buildings, such as office buildings, making them largely self-sufficient in energy production. One major bank building (ING Group\'s Amsterdam headquarters) in the Netherlands was constructed to be autonomous and artistic as well. ### 2000s {#s_2} In 2002, British architects Brenda and Robert Vale wrote: > It is quite possible in all parts of Australia to construct a \'house with no bills\', which would be comfortable without heating and cooling, which would make its own electricity, collect its own water and deal with its own waste\...These houses can be built now, using off-the-shelf techniques. It is possible to build a \"house with no bills\" for the same price as a conventional house, but it would be (25%) smaller. ## Advantages As an architect or engineer becomes more concerned with the disadvantages of transportation networks, and dependence on distant resources, their designs tend to include more autonomous elements. The historic path to autonomy was a concern for secure sources of heat, power, water and food. A nearly parallel path toward autonomy has been to start with a concern for environmental impacts, which cause disadvantages. Autonomous buildings can increase security and reduce environmental impacts by using on-site resources (such as sunlight and rain) that would otherwise be wasted. Autonomy often dramatically reduces the costs and impacts of networks that serve the building, because autonomy short-circuits the multiplying inefficiencies of collecting and transporting resources. Other impacted resources, such as oil reserves and the retention of the local watershed, can often be cheaply conserved by thoughtful designs. Autonomous buildings are usually energy-efficient in operation, and therefore cost-efficient, for the obvious reason that smaller energy needs are easier to satisfy off-grid. But they may substitute energy production or other techniques to avoid diminishing returns in extreme conservation. An autonomous structure is not always environmentally friendly. The goal of independence from support systems is associated with, but not identical to, other goals of environmentally responsible green building. However, autonomous buildings also usually include some degree of sustainability through the use of renewable energy and other renewable resources, producing no more greenhouse gases than they consume, and other measures. ## Disadvantages First and fundamentally, independence is a matter of degree. For example, eliminating dependence on the electrical grid is relatively easy. In contrast, running an efficient, reliable food source can be a chore. Living within an autonomous shelter may also require sacrifices in lifestyle or social opportunities. Even the most comfortable and technologically advanced autonomous homes could require alterations of residents\' behavior. Some may not welcome the extra chores. The Vails described some clients\' experiences as inconvenient, irritating, isolating, or even as an unwanted full-time job. A well-designed building can reduce this issue, but usually at the expense of reduced autonomy. An autonomous house must be custom-built (or extensively retrofitted) to suit the climate and location. Passive solar techniques, alternative toilet and sewage systems, thermal massing designs, basement battery systems, efficient windowing, and the array of other design tactics require some degree of non-standard construction, added expense, ongoing experimentation and maintenance, and also have an effect on the psychology of the space. ## Systems ### Water There are many methods of collecting and conserving water. Use reduction is cost-effective. Greywater systems reuse drained wash water to flush toilets or to water lawns and gardens. Greywater systems can halve the water use of most residential buildings; however, they require the purchase of a sump, greywater pressurization pump, and secondary plumbing. Some builders are installing waterless urinals and even composting toilets that eliminate water usage in sewage disposal. The classic solution with minimal life-style changes is using a well. Once drilled, a well-foot requires substantial power. However, advanced well-foots can reduce power usage by twofold or more from older models. Well water can be contaminated in some areas. The Sono arsenic filter eliminates unhealthy arsenic in well water. However drilling a well is an uncertain activity, with aquifers depleted in some areas. It can also be expensive. In regions with sufficient rainfall, it is often more economical to design a building to use rainwater harvesting, with supplementary water deliveries in a drought. Rain water makes excellent soft washwater, but needs antibacterial treatment. If used for drinking, mineral supplements or mineralization is necessary. Most desert and temperate climates get at least 250 mm of rain per year. This means that a typical one-story house with a greywater system can supply its year-round water needs from its roof alone. In the driest areas, it might require a cistern of 30 m3. Many areas average 13 mm of rain per week, and these can use a cistern as small as 10 m3. In many areas, it is difficult to keep a roof clean enough for drinking. To reduce dirt and bad tastes, systems use a metal collecting-roof and a \"roof cleaner\" tank that diverts the first 40 liters. Cistern water is usually chlorinated, though reverse osmosis systems provide even better quality drinking water. In the classic Roman house (\"Domus\"), household water was provided from a cistern (the \"impluvium\"), which was a decorative feature of the atrium, the house\'s main public space. It was fed by downspout tiles from the inward-facing roof-opening (the \"compluvium\"). Often water lilies were grown in it to purify the water. Wealthy households often supplemented the rain with a small fountain fed from a city\'s cistern. The impluvium always had an overflow drain so it could not flood the house. Modern cisterns are usually large plastic tanks. Gravity tanks on short towers are reliable, so pump repairs are less urgent. The least expensive bulk cistern is a fenced pond or pool at ground level. Reducing autonomy reduces the size and expense of cisterns. Many autonomous homes can reduce water use below 10 USgal per person per day, so that in a drought a month of water can be delivered inexpensively via truck. Self-delivery is often possible by installing fabric water tanks that fit the bed of a pick-up truck. It can be convenient to use the cistern as a heat sink or trap for a heat pump or air conditioning system; however this can make cold drinking water warm, and in drier years may decrease the efficiency of the HVAC system. Solar stills can efficiently produce drinking water from ditch water or cistern water, especially high-efficiency multiple effect humidification designs, which separate the evaporator(s) and condenser(s). New technologies, like reverse osmosis can create unlimited amounts of pure water from polluted water, ocean water, and even from humid air. Watermakers are available for yachts that convert seawater and electricity into potable water and brine. Atmospheric water generators extract moisture from dry desert air and filter it to pure water. ### Sewage #### Resource Composting toilets use bacteria to decompose human feces into useful, odourless, sanitary compost. The process is sanitary because soil bacteria eat the human pathogens as well as most of the mass of the waste. Nevertheless, most health authorities forbid direct use of \"humanure\" for growing food. The risk is microbial and viral contamination, as well as heavy metal toxicity. In a dry composting toilet, the waste is evaporated or digested to gas (mostly carbon dioxide) and vented, so a toilet produces only a few pounds of compost every six months. To control the odor, modern toilets use a small fan to keep the toilet under negative pressure, and exhaust the gasses to a vent pipe. Some home sewage treatment systems use biological treatment, usually beds of plants and aquaria, that absorb nutrients and bacteria and convert greywater and sewage to clear water. This odor- and color-free reclaimed water can be used to flush toilets and water outside plants. When tested, it approaches standards for potable water. In climates that freeze, the plants and aquaria need to be kept in a small greenhouse space. Good systems need about as much care as a large aquarium. Electric incinerating toilets turn excrement into a small amount of ash. They are cool to the touch, have no water and no pipes, and require an air vent in a wall. They are used in remote areas where use of septic tanks is limited, usually to reduce nutrient loads in lakes. NASA\'s bioreactor is an extremely advanced biological sewage system. It can turn sewage into air and water through microbial action. NASA plans to use it in the crewed Mars mission. Another method is NASA\'s urine-to-water distillation system. A big disadvantage of complex biological sewage treatment systems is that if the house is empty, the sewage system biota may starve to death. #### Waste Sewage handling is essential for public health. Many diseases are transmitted by poorly functioning sewage systems. The standard system is a tiled leach field combined with a septic tank. The basic idea is to provide a small system with primary sewage treatment. Sludge settles to the bottom of the septic tank, is partially reduced by anaerobic digestion, and fluid is dispersed in the leach field. The leach field is usually under a yard growing grass. Septic tanks can operate entirely by gravity, and if well managed, are reasonably safe. Septic tanks have to be pumped periodically by a vacuum truck to eliminate non reducing solids. Failure to pump a septic tank can cause overflow that damages the leach field, and contaminates ground water. Septic tanks may also require some lifestyle changes, such as not using garbage disposals, minimizing fluids flushed into the tank, and minimizing non-digestible solids flushed into the tank. For example, septic safe toilet paper is recommended. However, septic tanks remain popular because they permit standard plumbing fixtures, and require few or no lifestyle sacrifices. Composting or packaging toilets make it economical and sanitary to throw away sewage as part of the normal garbage collection service. They also reduce water use by half, and eliminate the difficulty and expense of septic tanks. However, they require the local landfill to use sanitary practices. Incinerator systems are quite practical. The ashes are biologically safe, and less than 1/10 the volume of the original waste, but like all incinerator waste, are usually classified as hazardous waste. Traditional methods of sewage handling include pit toilets, latrines, and outhouses. These can be safe, inexpensive and practical. They are still used in many regions. ### Storm drains {#storm_drains} Drainage systems are a crucial compromise between human habitability and a secure, sustainable watershed. Paved areas and lawns or turf do not allow much precipitation to filter through the ground to recharge aquifers. They can cause flooding and damage in neighbourhoods, as the water flows over the surface towards a low point. Typically, elaborate, capital-intensive storm sewer networks are engineered to deal with stormwater. In some cities, such as the Victorian era London sewers or much of the old City of Toronto, the storm water system is combined with the sanitary sewer system. In the event of heavy precipitation, the load on the sewage treatment plant at the end of the pipe becomes too great to handle and raw sewage is dumped into holding tanks, and sometimes into surface water. Autonomous buildings can address precipitation in a number of ways. If a water-absorbing swale for each yard is combined with permeable concrete streets, storm drains can be omitted from the neighbourhood. This can save more than \$800 per house (1970s) by eliminating storm drains. One way to use the savings is to purchase larger lots, which permits more amenities at the same cost. Permeable concrete is an established product in warm climates, and in development for freezing climates. In freezing climates, the elimination of storm drains can often still pay for enough land to construct swales (shallow water collecting ditches) or water impeding berms instead. This plan provides more land for homeowners and can offer more interesting topography for landscaping. Additionally, a green roof captures precipitation and uses the water to grow plants. It can be built into a new building or used to replace an existing roof. ### Electricity Further information: Zero emissions, Zero-energy building Since electricity is an expensive utility, the first step towards autonomy is to design a house and lifestyle to reduce demand. LED lights, laptop computers and gas-powered refrigerators save electricity, although gas-powered refrigerators are not very efficient. There are also superefficient electric refrigerators, such as those produced by the Sun Frost company, some of which use only about half as much electricity as a mass-market energy star-rated refrigerator. Using a solar roof, solar cells can provide electric power. Solar roofs can be more cost-effective than retrofitted solar power, because buildings need roofs anyway. Modern solar cells last about 40 years, which makes them a reasonable investment in some areas. At a sufficient angle, solar cells are cleaned by run-off rain water and therefore have almost no life-style impact. Many areas have long winter nights or dark cloudy days. In these climates, a solar installation might not pay for itself or large battery storage systems are necessary to achieve electric self-sufficiency. In stormy or windy climates, wind turbines can replace or significantly supplement solar power. The average autonomous house needs only one small wind turbine, 5 metres or less in diameter. On a 30-metre (100-foot) tower, this turbine can provide enough power to supplement solar power on cloudy days. Commercially available wind turbines use sealed, one-moving-part AC generators and passive, self-feathering blades for years of operation without service. The main advantage of wind power is that larger wind turbines have a lower per-watt cost than solar cells, provided there is wind. Turbine location is critical: just as some locations lack sun for solar cells, many areas lack enough wind to make a turbine pay for itself. In the Great Plains of the United States, a 10-metre (33-foot) turbine can supply enough energy to heat and cool a well-built all-electric house. Economic use in other areas requires research, and possibly a site survey. Some sites have access to a stream with a change in elevation. These sites can use small hydropower systems to generate electricity. If the difference in elevation is above 30 metres (100 feet), and the stream runs in all seasons, this can provide continuous power with a small, inexpensive installation. Lower changes of elevation require larger installations or dams, and can be less efficient. Clogging at the turbine intake can be a practical problem. The usual solution is a small pool and waterfall (a penstock) to carry away floating debris. Another solution is to utilize a turbine that resists debris, such as a Gorlov helical turbine or Ossberger turbine. During times of low demand, excess power can be stored in batteries for future use. However, batteries need to be replaced every few years. In many areas, battery expenses can be eliminated by attaching the building to the electric power grid and operating the power system with net metering. Utility permission is required, but such cooperative generation is legally mandated in some areas (for example, California). A grid-based building is less autonomous, but more economical and sustainable with fewer lifestyle sacrifices. In rural areas the grid\'s cost and impacts can be reduced by using single-wire earth return systems (for example, the MALT-system). In areas that lack access to the grid, battery size can be reduced with a generator to recharge the batteries during energy droughts such as extended fogs. Auxiliary generators are usually run from propane, natural gas, or sometimes diesel. An hour of charging usually provides a day of operation. Modern residential chargers permit the user to set the charging times, so the generator is quiet at night. Some generators automatically test themselves once per week. Recent advances in passively stable magnetic bearings may someday permit inexpensive storage of power in a flywheel in a vacuum. Research groups like Canada\'s Ballard Power Systems are also working to develop a \"regenerative fuel cell\", a device that can generate hydrogen and oxygen when power is available, and combine these efficiently when power is needed. Earth batteries tap electric currents in the earth called telluric current. They can be installed anywhere in the ground. They provide only low voltages and current. They were used to power telegraphs in the 19th century. As appliance efficiencies increase, they may become practical. Microbial fuel cells and thermoelectric generators allow electricity to be generated from biomass. The plant can be dried, chopped and converted or burned as a whole, or it can be left alive so that waste saps from the plant can be converted by bacteria. ### Heating Most autonomous buildings are designed to use insulation, thermal mass and passive solar heating and cooling. Examples of these are trombe walls and other technologies as skylights. Passive solar heating can heat most buildings in even the mild and chilly climates. In colder climates, extra construction costs can be as little as 15% more than new, conventional buildings. In warm climates, those having less than two weeks of frosty nights per year, there is no cost impact. The basic requirement for passive solar heating is that the solar collectors must face the prevailing sunlight (south in the Northern Hemisphere, north in the Southern Hemisphere), and the building must incorporate thermal mass to keep it warm in the night. A recent, somewhat experimental solar heating system \"Annualized geo solar heating\" is practical even in regions that get little or no sunlight in winter. It uses the ground beneath a building for thermal mass. Precipitation can carry away the heat, so the ground is shielded with `{{nowrap\|6 m}}`{=mediawiki} skirts of plastic insulation. The thermal mass of this system is sufficiently inexpensive and large that it can store enough summer heat to warm a building for the whole winter, and enough winter cold to cool the building in summer. In annualized geo solar systems, the solar collector is often separate from (and hotter or colder than) the living space. The building may actually be constructed from insulation, for example, straw-bale construction. Some buildings have been aerodynamically designed so that convection via ducts and interior spaces eliminates any need for electric fans. A more modest \"daily solar\" design is practical. For example, for about a 15% premium in building costs, the Passivhaus building codes in Europe use high performance insulating windows, R-30 insulation, HRV ventilation, and a small thermal mass. With modest changes in the building\'s position, modern krypton- or argon-insulated windows permit normal-looking windows to provide passive solar heat without compromising insulation or structural strength. If a small heater is available for the coldest nights, a slab or basement cistern can inexpensively provide the required thermal mass. Passivhaus building codes, in particular, bring unusually good interior air quality, because the buildings change the air several times per hour, passing it through a heat exchanger to keep heat inside. In all systems, a small supplementary heater increases personal security and reduces lifestyle impacts for a small reduction of autonomy. The two most popular heaters for ultra-high-efficiency houses are a small heat pump, which also provides air conditioning, or a central hydronic (radiator) air heater with water recirculating from the water heater. Passivhaus designs usually integrate the heater with the ventilation system. Earth sheltering and windbreaks can also reduce the absolute amount of heat needed by a building. Several feet below the earth, temperature ranges from 4 C in North Dakota to 26 C, in Southern Florida. Wind breaks reduce the amount of heat carried away from a building. Rounded, aerodynamic buildings also lose less heat. An increasing number of commercial buildings use a combined cycle with cogeneration to provide heating, often water heating, from the output of a natural gas reciprocating engine, gas turbine or stirling electric generator. Houses designed to cope with interruptions in civil services generally incorporate a wood stove, or heat and power from diesel fuel or bottled gas, regardless of their other heating mechanisms. Electric heaters and electric stoves may provide pollution-free heat (depending on the power source), but use large amounts of electricity. If enough electricity is provided by solar panels, wind turbines, or other means, then electric heaters and stoves become a practical autonomous design. ### Water heating {#water_heating} Hot water heat recycling units recover heat from water drain lines. They increase a building\'s autonomy by decreasing the heat or fuel used to heat water. They are attractive because they have no lifestyle changes. Current practical, comfortable domestic water-heating systems combine a solar preheating system with a thermostatic gas-powered flow-through heater, so that the temperature of the water is consistent, and the amount is unlimited. This reduces life-style impacts at some cost in autonomy. Solar water heaters can save large amounts of fuel. Also, small changes in lifestyle, such as doing laundry, dishes and bathing on sunny days, can greatly increase their efficiency. Pure solar heaters are especially useful for laundries, swimming pools and external baths, because these can be scheduled for use on sunny days. The basic trick in a solar water heating system is to use a well-insulated holding tank. Some systems are vacuum- insulated, acting something like large thermos bottles. The tank is filled with hot water on sunny days, and made available at all times. Unlike a conventional tank water heater, the tank is filled only when there is sunlight. Good storage makes a smaller, higher-technology collector feasible. Such collectors can use relatively exotic technologies, such as vacuum insulation, and reflective concentration of sunlight. Cogeneration systems produce hot water from waste heat. They usually get the heat from the exhaust of a generator or fuel cell. Heat recycling, cogeneration and solar pre-heating can save 50--75% of the gas otherwise used. Also, some combinations provide redundant reliability by having several sources of heat. Some authorities advocate replacing bottled gas or natural gas with biogas. However, this is usually impractical unless live-stock are on-site. The wastes of a single family are usually insufficient to produce enough methane for anything more than small amounts of cooking. ### Cooling Annualized geo solar buildings often have buried, sloped water-tight skirts of insulation that extend 6 m from the foundations, to prevent heat leakage between the earth used as thermal mass, and the surface. Less dramatic improvements are possible. Windows can be shaded in summer. Eaves can be overhung to provide the necessary shade. These also shade the walls of the house, reducing cooling costs. Another trick is to cool the building\'s thermal mass at night, perhaps with a whole-house fan and then cool the building from the thermal mass during the day. It helps to be able to route cold air from a sky-facing radiator (perhaps an air heating solar collector with an alternate purpose) or evaporative cooler directly through the thermal mass. On clear nights, even in tropical areas, sky-facing radiators can cool below freezing. If a circular building is aerodynamically smooth, and cooler than the ground, it can be passively cooled by the \"dome effect.\" Many installations have reported that a reflective or light-colored dome induces a local vertical heat-driven vortex that sucks cooler overhead air downward into a dome if the dome is vented properly (a single overhead vent, and peripheral vents). Some people have reported a temperature differential as high as `{{nowrap\|8 °C}}`{=mediawiki} (`{{nowrap\|15 °F}}`{=mediawiki}) between the inside of the dome and the outside. Buckminster Fuller discovered this effect with a simple house design adapted from a grain silo, and adapted his Dymaxion house and geodesic domes to use it. Refrigerators and air conditioners operating from the waste heat of a diesel engine exhaust, heater flue or solar collector are entering use. These use the same principles as a gas refrigerator. Normally, the heat from a flue powers an \"absorptive chiller\". The cold water or brine from the chiller is used to cool air or a refrigerated space. Cogeneration is popular in new commercial buildings. In current cogeneration systems small gas turbines or stirling engines powered from natural gas produce electricity and their exhaust drives an absorptive chiller. A truck trailer refrigerator operating from the waste heat of a tractor\'s diesel exhaust was demonstrated by NRG Solutions, Inc. NRG developed a hydronic ammonia gas heat exchanger and vaporizer, the two essential new, not commercially available components of a waste heat driven refrigerator. A similar scheme (multiphase cooling) can be by a multistage evaporative cooler. The air is passed through a spray of salt solution to dehumidify it, then through a spray of water solution to cool it, then another salt solution to dehumidify it again. The brine has to be regenerated, and that can be done economically with a low-temperature solar still. Multiphase evaporative coolers can lower the air\'s temperature by 50 °F (28 °C), and still control humidity. If the brine regenerator uses high heat, it also partially sterilises to the air. If enough electric power is available, cooling can be provided by conventional air conditioning using a heat pump. ### Food production {#food_production} Food production has often been included in historic autonomous projects to provide security. Skilled, intensive gardening can support an adult from as little as 100 square meters of land per person, possibly requiring the use of organic farming and aeroponics. Some proven intensive, low-effort food-production systems include urban gardening (indoors and outdoors). Indoor cultivation may be set up using hydroponics, while outdoor cultivation may be done using permaculture, forest gardening, no-till farming, and do nothing farming. Greenhouses are also sometimes included. Sometimes they are also outfitted with irrigation systems or heat sink systems which can respectively irrigate the plants or help to store energy from the sun and redistribute it at night (when the greenhouses starts to cool down).	2025-06-20T00:00:00
3,027	Anubis	Anubis (`{{IPAc-en\|ə\|ˈ\|nj\|uː\|b\|ᵻ\|s\|audio=LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-Anubis.wav}}`{=mediawiki}; Ἄνουβις), also known as Inpu, Inpw, Jnpw, or Anpu in Ancient Egyptian (translit=Anoup), is the god of funerary rites, protector of graves, and guide to the underworld in ancient Egyptian religion, usually depicted as a canine or a man with a canine head. Like many ancient Egyptian deities, Anubis assumed different roles in various contexts. Depicted as a protector of graves as early as the First Dynasty (c. 3100), Anubis was also an embalmer. By the Middle Kingdom (c. 2055--1650 BC) he was replaced by Osiris in his role as lord of the underworld. One of his prominent roles was as a god who ushered souls into the afterlife. He attended the weighing scale during the \"Weighing of the Heart\", in which it was determined whether a soul would be allowed to enter the realm of the dead. Anubis is one of the most frequently depicted and mentioned gods in the Egyptian pantheon; however, few major myths involved him. Anubis was depicted in black, a color that symbolized regeneration, life, the soil of the Nile River, and the discoloration of the corpse after embalming. Anubis is associated with Wepwawet, another Egyptian god portrayed with a dog\'s head or in canine form, but with grey or white fur. Historians assume that the two figures were eventually combined. Anubis\' female counterpart is Anput. His daughter is the serpent goddess Kebechet. ## Name \"Anubis\" is a Greek rendering of this god\'s Egyptian name. Before the Greeks arrived in Egypt, around the 7th century BC, the god was known as Anpu or Inpu. The root of the name in ancient Egyptian language means \"a royal child.\" Inpu has a root to \"inp\", which means \"to decay.\" The god was also known as \"First of the Westerners,\" \"Lord of the Sacred Land,\" \"He Who is Upon his Sacred Mountain,\" \"Ruler of the Nine Bows,\" \"The Dog who Swallows Millions,\" \"Master of Secrets,\" \"He Who is in the Place of Embalming,\" and \"Foremost of the Divine Booth.\" The positions that he had were also reflected in the titles he held such as \"He Who Is upon His Mountain,\" \"Lord of the Sacred Land,\" \"Foremost of the Westerners,\" and \"He Who Is in the Place of Embalming.\" In the Old Kingdom (c. 2686 BC), the standard way of writing his name in hieroglyphs was composed of the sound signs *inpw* followed by a jackal over a ḥtp sign: i-n:p-w-C6 A new form with the jackal on a tall stand appeared in the late Old Kingdom and became common thereafter: i-n:p-w-E16 Anubis\' name jnpw was possibly pronounced `{{IPA\|[aˈna.pʰa(w)]}}`{=mediawiki}, based on Coptic Anoup and the Akkadian transcription `{{Transliteration\|akk-x-midbabyl\|{{angbr\|a-na-pa}}}}`{=mediawiki} (𒀀𒈾𒉺}}) in the name \"Reanapa\" that appears in Amarna letter EA 315. However, this transcription may also be interpreted as rˁ-nfr, a name similar to that of Prince Ranefer of the Fourth Dynasty. ## History In Egypt\'s Early Dynastic period (c. 3100), Anubis was portrayed in full animal form, with a \"jackal\" head and body. A jackal god, probably Anubis, is depicted in stone inscriptions from the reigns of Hor-Aha, Djer, and other pharaohs of the First Dynasty. Since Predynastic Egypt, when the dead were buried in shallow graves, jackals had been strongly associated with cemeteries because they were scavengers which uncovered human bodies and ate their flesh. In the spirit of \"fighting like with like,\" a jackal was chosen to protect the dead, because \"a common problem (and cause of concern) must have been the digging up of bodies, shortly after burial, by jackals and other wild dogs which lived on the margins of the cultivation.\" In the Old Kingdom, Anubis was the most important god of the dead. He was replaced in that role by Osiris during the Middle Kingdom (2000--1700 BC). In the Roman era, which started in 30 BC, tomb paintings depict him holding the hand of deceased persons to guide them to Osiris. The parentage of Anubis varied between myths, times and sources. In early mythology, he was portrayed as a son of Ra. In the Coffin Texts, which were written in the First Intermediate Period (c. 2181--2055 BC), Anubis is the son of either the cow goddess Hesat or the cat-headed Bastet. Another tradition depicted him as the son of Ra and Nephthys. More commonly, however, he is recognized as the offspring of Osiris and Isis.In later periods, particularly during the Ptolemaic era, Anubis was sometimes described as the son of Isis and Serapis, a Hellenized form of Osiris designed to appeal to Egypt\'s growing Greek population. The Greek Plutarch (c. 40--120 AD) reported a tradition that Anubis was the illegitimate son of Nephthys and Osiris, but that he was adopted by Osiris\'s wife Isis: George Hart sees this story as an \"attempt to incorporate the independent deity Anubis into the Osirian pantheon.\" An Egyptian papyrus from the Roman period (30--380 AD) simply called Anubis the \"son of Isis.\" In Nubia, Anubis was seen as the husband of his mother Nephthys. In the Ptolemaic period (350--30 BC), when Egypt became a Hellenistic kingdom ruled by Greek pharaohs, Anubis was merged with the Greek god Hermes, becoming Hermanubis. The two gods were considered similar because they both guided souls to the afterlife. The center of this cult was in uten-ha/Sa-ka/ Cynopolis, a place whose Greek name means \"city of dogs.\" In Book XI of The Golden Ass by Apuleius, there is evidence that the worship of this god was continued in Rome through at least the 2nd century. Indeed, Hermanubis also appears in the alchemical and hermetical literature of the Middle Ages and the Renaissance. Although the Greeks and Romans typically scorned Egyptian animal-headed gods as bizarre and primitive (Anubis was mockingly called \"Barker\" by the Greeks), Anubis was sometimes associated with Sirius in the heavens and Cerberus and Hades in the underworld. In his dialogues, Plato often has Socrates utter oaths \"by the dog\" (Greek: kai me ton kuna), \"by the dog of Egypt\", and \"by the dog, the god of the Egyptians\", both for emphasis and to appeal to Anubis as an arbiter of truth in the underworld. ## Roles ### Embalmer As jmy-wt (Imiut or the Imiut fetish) \"He who is in the place of embalming\", Anubis was associated with mummification. He was also called ḫnty zḥ-nṯr \"He who presides over the god\'s booth\", in which \"booth\" could refer either to the place where embalming was carried out or the pharaoh\'s burial chamber. In the Osiris myth, Anubis helped Isis to embalm Osiris. Indeed, when the Osiris myth emerged, it was said that after Osiris had been killed by Set, Osiris\'s organs were given to Anubis as a gift. With this connection, Anubis became the patron god of embalmers; during the rites of mummification, illustrations from the Book of the Dead often show a wolf-mask-wearing priest supporting the upright mummy. ### Protector of tombs {#protector_of_tombs} Anubis was a protector of graves and cemeteries. Several epithets attached to his name in Egyptian texts and inscriptions referred to that role. Khenty-Amentiu, which means \"foremost of the westerners\" and was also the name of a different canine funerary god, alluded to his protecting function because the dead were usually buried on the west bank of the Nile. He took other names in connection with his funerary role, such as tpy-ḏw.f (Tepy-djuef) \"He who is upon his mountain\" (i.e. keeping guard over tombs from above) and nb-t3-ḏsr (Neb-ta-djeser) \"Lord of the sacred land\", which designates him as a god of the desert necropolis. The Jumilhac papyrus recounts another tale where Anubis protected the body of Osiris from Set. Set attempted to attack the body of Osiris by transforming himself into a leopard. Anubis stopped and subdued Set, however, and he branded Set\'s skin with a hot iron rod. Anubis then flayed Set and wore his skin as a warning against evil-doers who would desecrate the tombs of the dead. Priests who attended to the dead wore leopard skin in order to commemorate Anubis\' victory over Set. The legend of Anubis branding the hide of Set in leopard form was used to explain how the leopard got its spots. Most ancient tombs had prayers to Anubis carved on them. ### Guide of souls {#guide_of_souls} By the late pharaonic era (664--332 BC), Anubis was often depicted as guiding individuals across the threshold from the world of the living to the afterlife. Though a similar role was sometimes performed by the cow-headed Hathor, Anubis was more commonly chosen to fulfill that function. Greek writers from the Roman period of Egyptian history designated that role as that of \"psychopomp\", a Greek term meaning \"guide of souls\" that they used to refer to their own god Hermes, who also played that role in Greek religion. Funerary art from that period represents Anubis guiding either men or women dressed in Greek clothes into the presence of Osiris, who by then had long replaced Anubis as ruler of the underworld. ### Weigher of hearts {#weigher_of_hearts} One of the roles of Anubis was as the \"Guardian of the Scales.\" The critical scene depicting the weighing of the heart, in the Book of the Dead, shows Anubis performing a measurement that determined whether the person was worthy of entering the realm of the dead (the underworld, known as Duat). By weighing the heart of a deceased person against ma\'at, who was often represented as an ostrich feather, Anubis dictated the fate of souls. Souls heavier than a feather would be devoured by Ammit, and souls lighter than a feather would ascend to a heavenly existence. ## Portrayal in art {#portrayal_in_art} Anubis was one of the most frequently represented deities in ancient Egyptian art. He is depicted in royal tombs as early as the First Dynasty. The god is typically treating a king\'s corpse, providing sovereign to mummification rituals and funerals, or standing with fellow gods at the Weighing of the Heart of the Soul in the Hall of Two Truths. One of his most popular representations is of him, with the body of a man and the head of a jackal with pointed ears, standing or kneeling, holding a gold scale while a heart of the soul is being weighed against Ma\'at\'s white truth feather. In the early dynastic period, he was depicted in animal form, as a black canine. Anubis\'s distinctive black color did not represent the animal, rather it had several symbolic meanings. It represented \"the discolouration of the corpse after its treatment with natron and the smearing of the wrappings with a resinous substance during mummification.\" Being the color of the fertile silt of the River Nile, to Egyptians, black also symbolized fertility and the possibility of rebirth in the afterlife. In the Middle Kingdom, Anubis was often portrayed as a man with the head of a jackal. The African jackal was the species depicted and the template of numerous Ancient Egyptian deities, including Anubis. An extremely rare depiction of him in fully human form was found in a chapel of Ramesses II in Abydos. Anubis is often depicted wearing a ribbon and holding a nḫ3ḫ3 \"flail\" in the crook of his arm. Another of Anubis\'s attributes was the jmy-wt or imiut fetish, named for his role in embalming. In funerary contexts, Anubis is shown either attending to a deceased person\'s mummy or sitting atop a tomb protecting it. New Kingdom tomb-seals also depict Anubis sitting atop the nine bows that symbolize his domination over the enemies of Egypt. <File:Anubis>, Ny Carlsberg Glyptotek, Copenhagen, 20220618 1030 6992.jpg\\|Statue of Anubis <File:KV17>, the tomb of Pharaoh Seti I of the Nineteenth Dynasty, Valley of the Kings, Egypt (49845804653).jpg\\|Wall relief of Anubis in (KV17) the tomb of Seti I, 19th Dynasty, Valley of the Kings <File:ThebanTomb335.png%7Calt=Fresco> of a mummy lying on a bier. Women stand at the head and foot of the bier, while a winged woman kneels in the register above\\|Isis, left, and Nephthys stand by as Anubis embalms the deceased, 13th century BC <File:Hermitage> hall 100 - Egyptian hall 46.jpg\\|Anubis receiving offerings, hieroglyph name in third column from left, 14th century BC; painted limestone; from Saqqara (Egypt) <File:Tutankhamun> jackal.jpg\\|The Anubis Shrine; 1336--1327 BC; painted wood and gold; 1.1 × 2.7 × 0.52 m; from the Valley of the Kings; Egyptian Museum (Cairo) <File:Anubis>, Anzio, Villa Pamphili, 1st-2nd century AD, Pario marble - Museo Gregoriano Egizio - Vatican Museums - DSC00818.jpg\\|Statue of Hermanubis, c. 100--138 AD, from Rome <File:Casa> degli Amorini Dorati. Fresco. 09.JPG\\|Anubis, Harpocrates, Isis and Serapis, antique fresco in Pompeii, Italy <File:Stela> of Siamun and Taruy worshipping Anubis MET 90.6.128 01.jpg\\|Stela of Siamun and Taruy worshipping Anubis <File:The> King with Anubis, Tomb of Haremhab MET DP234736.jpg\\|The king with Anubis, from the tomb of Horemheb; 1323-1295 BC; tempera on paper; Metropolitan Museum of Art <File:Anubis> Amulet MET DP109371.jpg\\|Anubis amulet; 664--30 BC; faience; height: 4.7 cm; Metropolitan Museum of Art <File:Recumbent> Anubis MET DP228716.jpg\\|Recumbent Anubis; 664--30 BC; limestone, originally painted black; height: 38.1 cm, length: 64 cm, width: 16.5 cm; Metropolitan Museum of Art <File:Statuette> of Anubis MET 38.5 EGDP022863.jpg\\|Statuette of Anubis; 332--30 BC; plastered and painted wood; 42.3 cm; Metropolitan Museum of Art ## Worship Although he does not appear in many myths, he was extremely popular with Egyptians and those of other cultures. The Greeks linked him to their god Hermes, the god who guided the dead to the afterlife. The pairing was later known as Hermanubis. Anubis was heavily worshipped because, despite modern beliefs, he gave the people hope. People marveled in the guarantee that their body would be respected at death, their soul would be protected and justly judged. Anubis had male priests who sported wood masks with the god\'s likeness when performing rituals. His cult center was at Cynopolis in Upper Egypt but memorials were built everywhere and he was universally revered in every part of the nation.	2025-06-20T00:00:00
3,036	Adoptionism	thumb\\|upright=1.2\\|Francesco Albani\'s The Baptism of Christ, when Jesus became one with God according to adoptionism Adoptionism, also called dynamic monarchianism, is an early Christian nontrinitarian theological doctrine, subsequently revived in various forms, which holds that Jesus was adopted as the Son of God at his baptism, his resurrection, or his ascension. How common adoptionist views were among early Christians is debated, but it appears to have been most popular in the first, second, and third centuries. Some scholars see adoptionism as the belief of the earliest followers of Jesus, based on the epistles of Paul and other early literature. However, adoptionist views sharply declined in prominence in the fourth and fifth centuries, as Church leaders condemned it as a heresy. ## Definition Adoptionism is one of two main forms of monarchianism (the other being modalism, which considers God to be one while working through the different \"modes\" or \"manifestations\" of God the Father, God the Son, and God the Holy Spirit, without limiting his modes or manifestations). Adoptionism denies the eternal pre-existence of Christ, and although it explicitly affirms his deity subsequent to events in his life, many classical trinitarians claim that the doctrine implicitly denies it by denying the constant hypostatic union of the eternal Logos to the human nature of Jesus. Under adoptionism, Jesus is divine and has been since his adoption although he is not equal to the Father per \"my Father is greater than I\" and as such is a kind of subordinationism. (However, the quoted scripture can be orthodoxically interpreted as the fact that in the Trinity the Father is the source without origin, while the Son eternally receives the divinity from the Father.) Adoptionism is sometimes but not always related to a denial of the virgin birth of Jesus. ## History ### Early Christianity {#early_christianity} #### Adoptionism and high Christology {#adoptionism_and_high_christology} Bart Ehrman claims that the New Testament writings contain two different Christologies, namely a \"low\" or adoptionist Christology, and a \"high\" or \"incarnation Christology\". The \"low Christology\" or \"adoptionist Christology\" is the belief \"that God exalted Jesus to be his Son by raising him from the dead\", thereby raising him to \"divine status\". The other early Christology is \"high Christology,\" which is \"the view that Jesus was a pre-existent divine being who became a human, did the Father\'s will on earth, and then was taken back up into heaven whence he had originally come,\" and from where he appeared on earth. The chronology of the development of these early Christologies is a matter of debate within contemporary scholarship. According to the \"evolutionary model\" or evolutionary theories proposed by Bousset, followed by Brown, the Christological understanding of Christ developed over time, from a low Christology to a high Christology, as witnessed in the Gospels.`{{Page needed\|date=May 2024}}`{=mediawiki} According to the evolutionary model, the earliest Christians believed that Jesus was a human who was exalted, and thus adopted as God\'s Son, when he was resurrected, signaling the nearness of the Kingdom of God, when all dead would be resurrected and the righteous exalted. Adoptionist concepts can be found in the Gospel of Mark. As Daniel Johansson notes, the majority of scholars hold Mark\'s Jesus as \"an exalted, but merely human figure\", especially when read in the apparent context of Jewish beliefs. Later beliefs shifted the exaltation to his baptism, birth, and subsequently to the idea of his eternal existence, as witnessed in the Gospel of John. Mark shifted the moment of when Jesus became the son to the baptism of Jesus, and later still Matthew and Luke shifted it to the moment of the divine conception, and finally John declared that Jesus had been with God from the beginning: \"In the beginning was the Word\". One notable passage that may have been cited by early adoptionists was what exactly God said at Jesus\'s baptism; three different versions are recorded. One of them, found in the Codex Bezae version of Luke 3:22, is \"You are my son; today I have begotten you.\" This seems to be quoted in Acts 13:32--33 as well (in all manuscripts, not just Bezae) and in Hebrews 5:5. Quotes from second and third century Christian writers almost always use this variant as well, with many fourth and fifth century writers continuing to use it, if occasionally with embarrassment; Augustine cites the line, for example, but clarifies God meant an eternal \"today\". Ehrman speculates that Orthodox scribes of the fourth and fifth century changed the passage in Luke to align with the version in Mark as a defense against adoptionists citing the passage in their favor. Since the 1970s, these late datings for the development of a \"high Christology\" have been contested, and a majority of scholars argue that this \"high Christology\" existed already before the writings of Paul. According to the \"New Religionsgeschichtliche Schule\", or the Early High Christology Club, which includes Martin Hengel, Larry Hurtado, N. T. Wright, and Richard Bauckham, this \"incarnation Christology\" or \"high Christology\" did not evolve over a longer time, but was a \"big bang\" of ideas which were already present at the start of Christianity, and took further shape in the first few decades of the church, as witnessed in the writings of Paul. Some \'Early High Christology\' proponents scholars argue that this \"high Christology\" may go back to Jesus himself. According to Ehrman, these two Christologies existed alongside each other, calling the \"low Christology\" an \"adoptionist Christology, and \"the \"high Christology\" an \"incarnation Christology\". Conversely, Michael Bird has argued that adoptionism did not first emerge until the 2nd century as a result of later theological debates and other socio-religious influences on the reading of certain biblical texts. #### New Testamental epistles {#new_testamental_epistles} Adoptionist theology may also be reflected in canonical epistles, the earliest of which pre-date the writing of the gospels. The letters of Paul the Apostle, for example, do not mention a virgin birth of Christ. Paul describes Jesus as \"born of a woman, born under the law\" and \"as to his human nature was a descendant of David\" in the Epistle to the Galatians and the Epistle to the Romans. Christian interpreters, however, take his statements in Philippians 2 to imply that Paul believed Jesus to have existed as equal to God before his incarnation. #### Shepherd of Hermas {#shepherd_of_hermas} The 2nd-century work Shepherd of Hermas may also have taught that Jesus was a virtuous man filled with the Holy Spirit and adopted as the Son.`{{refn\|group=note\|"The Holy Pre-existent Spirit. Which created the whole creation, God made to dwell in flesh that he desired. This flesh, therefore, in which the Holy Spirit dwelt, was subject unto the Spirit, walking honorably in holiness and purity, without in any way defiling the Spirit. When then it had lived honorably in chastity, and had labored with the Spirit, and had cooperated with it in everything, behaving itself boldly and bravely, he chose it as a partner with the Holy Spirit; for the career of this flesh pleased [the Lord], seeing that, as possessing the Holy Spirit, it was not defiled upon the earth. He therefore took the son as adviser and the glorious angels also, that this flesh too, having served the Spirit unblamably, might have some place of sojourn, and might not seem to have lost the reward for its service; for all flesh, which is found undefiled and unspotted, wherein the Holy Spirit dwelt, shall receive a reward."<ref>{{Cite web\|url=http://www.earlychristianwritings.com/text/shepherd-lightfoot.html\|title=The Shepherd of Hermas (Lightfoot translation)\|website=www.earlychristianwritings.com}}</ref>}}`{=mediawiki} While the Shepherd of Hermas was popular and sometimes bound with the canonical scriptures, it did not retain canonical status, if it ever had it. #### Theodotus of Byzantium {#theodotus_of_byzantium} Theodotus of Byzantium (`{{abbr\|fl.\|[[floruit]]}}`{=mediawiki} late 2nd century), a Valentinian Gnostic, was the most prominent exponent of adoptionism. According to Hippolytus of Rome (Philosophumena, VII, xxiii) Theodotus taught that Jesus was a man born of a virgin, according to the Council of Jerusalem, that he lived like other men, and was most pious. At his baptism in the Jordan the \"Christ\" came down upon the man Jesus, in the likeness of a dove (Philosophumena, VII, xxiii), but Jesus was not himself God until after his resurrection. Adoptionism was declared heresy at the end of the 3rd century and was rejected by the Synods of Antioch and the First Council of Nicaea, which defined the orthodox doctrine of the Trinity and identified the man Jesus with the eternally begotten Son or Word of God in the Nicene Creed. The belief was also declared heretical by Pope Victor I. #### Ebionites Adoptionism was also adhered to by the Jewish Christians known as Ebionites, who, according to Epiphanius in the 4th century, believed that Jesus was chosen on account of his sinless devotion to the will of God. The Ebionites were a Jewish Christian movement that existed during the early centuries of the Christian Era. They show strong similarities with the earliest form of Jewish Christianity, and their specific theology may have been a \"reaction to the law-free Gentile mission\". They regarded Jesus as the Messiah while rejecting his divinity and his virgin birth, and insisted on the necessity of following Jewish law and rites. They used the Gospel of the Ebionites, one of the Jewish--Christian gospels; the Hebrew Book of Matthew starting at chapter 3; revered James the brother of Jesus (James the Just); and rejected Paul the Apostle as an apostate from the Law. Their name (Ebionaioi, derived from ebyonim, meaning `{{gloss\|the poor}}`{=mediawiki} or `{{gloss\|poor ones}}`{=mediawiki}) suggests that they placed a special value on voluntary poverty. Distinctive features of the Gospel of the Ebionites include the absence of the virgin birth and of the genealogy of Jesus; an Adoptionist Christology,`{{refn\|group=note\|{{harvnb\|Kloppenborg\|1994\|pp=435–9}}; p. 435 – "This belief, known as "adoptionism", held that Jesus was not divine by nature or by birth, but that God chose him to become his son, i.e., adopted him."}}`{=mediawiki} in which Jesus is chosen to be God\'s Son at the time of his Baptism; the abolition of the Jewish sacrifices by Jesus; and an advocacy of vegetarianism.`{{refn\|group=note\|{{harvnb\|Vielhauer\|Strecker\|1991\|pp=166–71}}; p. 168 – "Jesus' task is to do away with the 'sacrifices'. In this saying (16.4–5), the hostility of the Ebionites against the Temple cult is documented."}}`{=mediawiki} ### Spanish Adoptionism {#spanish_adoptionism} Iberian Adoptionism was a theological position which was articulated in Umayyad and Christian-held regions of the Iberian Peninsula in the 8th and 9th centuries. The issue seems to have begun with the claim of archbishop Elipandus of Toledo that -- in respect to his human nature -- Christ was adoptive Son of God. Another leading advocate of this Christology was Felix of Urgel. In the Iberian peninsula, adoptionism was opposed by Beatus of Liebana, and in the Carolingian territories, the Adoptionist position was condemned by Pope Hadrian I, Alcuin of York, Agobard, and officially in Carolingian territory by the Council of Frankfurt (794). Despite the shared name of \"adoptionism\" the Spanish Adoptionist Christology appears to have differed sharply from the adoptionism of early Christianity. Spanish advocates predicated the term adoptivus of Christ only in respect to his humanity; once the divine Son \"emptied himself\" of divinity and \"took the form of a servant\" (Philippians 2:7), Christ\'s human nature was \"adopted\" as divine. Historically, many scholars have followed the Adoptionists\' Carolingian opponents in labeling Spanish Adoptionism as a minor revival of \"Nestorian\" Christology. John C. Cavadini has challenged this notion by attempting to take the Spanish Christology in its own Spanish/North African context in his study, The Last Christology of the West: Adoptionism in Spain and Gaul, 785--820. ### Scholastic Neo-adoptionism {#scholastic_neo_adoptionism} A third wave was the revived form (\"Neo-adoptionism\") of Peter Abelard in the 12th century. Later, various modified and qualified Adoptionist tenets emerged from some theologians in the 14th century. Duns Scotus (1300) and Durandus of Saint-Pourçain (1320) admit the term filius adoptivus in a qualified sense. In more recent times the Jesuit Gabriel Vásquez, and the Lutheran divines Georgius Calixtus and Johann Ernst Immanuel Walch, have defended adoptionism as essentially orthodox. ### Modern adoptionist groups {#modern_adoptionist_groups} A form of adoptionism surfaced in Unitarianism during the 16th and 17th in Polish Brethren and the 18th century as denial of the virgin birth became increasingly common, led by the views of Joseph Priestley and others. A similar form of adoptionism was expressed in the writings of James Strang, a Latter Day Saint leader who founded the Church of Jesus Christ of Latter Day Saints (Strangite) after the death of Joseph Smith in 1844. In his Book of the Law of the Lord, a purported work of ancient scripture found and translated by Strang, he offers an essay entitled \"Note on the Sacrifice of Christ\" in which he explains his unique (for Mormonism as a whole) doctrines on the subject. Jesus Christ, said Strang, was the natural-born son of Mary and Joseph, who was chosen from before all time to be the Savior of mankind, but who had to be born as an ordinary mortal of two human parents (rather than being begotten by the Father or the Holy Spirit) to be able to truly fulfill his Messianic role. Strang claimed that the earthly Christ was in essence \"adopted\" as God\'s son at birth, and fully revealed as such during the Transfiguration. After proving himself to God by living a perfectly sinless life, he was enabled to provide an acceptable sacrifice for the sins of men, prior to his resurrection and ascension. The Christian Community, an esoteric Christian denomination informed by the teachings of Rudolf Steiner, assumes a high adoptionist Christology that treats Jesus and God the Son as separate beings until they are joined at baptism. \"Steiner\'s Christology is discussed as a central element of his thought in Johannes Hemleben, Rudolf Steiner: A Documentary Biography, trans. Leo Twyman (East Grinstead, Sussex: Henry Goulden, 1975), pp. 96-100. From the perspective of orthodox Christianity, it may be said that Steiner combined a docetic understanding of Christ\'s nature with the Adoptionist heresy.\"	2025-06-20T00:00:00
3,037	Apollinarism	Apollinarism or Apollinarianism is a Christological position proposed by Apollinaris of Laodicea that argues that Jesus had a human body and sensitive human soul, but a divine mind and not a human rational mind, the Divine Logos taking the place of the latter. It was deemed heretical by the First Council of Constantinople in 381 and virtually died out within the following decades. ## History The Trinity had been recognized at the First Council of Nicaea in 325, but debate about exactly what it meant continued. A rival to the more common belief that Jesus Christ had two natures was monophysitism (\"one nature\"), the doctrine that Christ had only one nature. Apollinarism and Eutychianism were two forms of monophysitism. Apollinaris\'s rejection of Christ having a human mind was considered an over-reaction to Arianism and its teaching that Christ was a lesser god. Theodoret charged Apollinaris with confounding the persons of the Godhead and giving in to the heretical ways of Sabellius. Basil of Caesarea accused him of abandoning the literal sense of the scripture, and taking it up wholly with the allegorical sense. His views were condemned in a Synod at Alexandria, under Athanasius of Alexandria, in 362, and later subdivided into several different heresies, the main ones of which were the Polemians and the Antidicomarianites. Apollinaris, considering the rational soul and spirit as essentially liable to sin and capable, at its best, of only precarious efforts, saw no way of saving Christ\'s impeccability and the infinite value of Redemption, except by the elimination of the human spirit from Jesus\' humanity, and the substitution of the Divine Logos in its stead. Apollinarism was declared to be a heresy in 381 by the First Council of Constantinople. ## Neo-Apollinarianism {#neo_apollinarianism} Christian philosopher William Lane Craig has proposed a neo-Apollinarian Christology in which the divine Logos completes the human nature of Christ. Craig says his proposal is tentative and he welcomes critique and interaction from other scholars. Craig also clarifies \"what I called a Neo-Apollinarian Christological model\" by stating that `{{blockquote\|What I argue in my Neo-Apollinarian proposal is that the ''Logos'' brought to the human body just those properties which would make it a complete human nature – things like [[rationality]], [[self-consciousness]], freedom of the will, and so forth. Christ already possessed those in his divine nature, and it is in virtue of those that we are created in the [[image of God]]. So when he brought those properties to the animal body – the human body – it completes it and makes it a human nature. Against Apollinarius, I want to say that Christ did have a complete human nature. He was truly God and truly man. Therefore his death on our behalf as our representative before God was efficacious.<ref>{{cite web\| url = https://www.reasonablefaith.org/media/reasonable-faith-podcast/does-dr.-craig-have-an-orthodox-christology/\| title = Does Dr. Craig Have an Orthodox Christology? {{!}} Podcast {{!}}`{=mediawiki} Reasonable Faith}} }}	2025-06-20T00:00:00
3,038	Acid–base reaction	thumb\\|upright=1.5\\|thumbtime=10\\|Video of reaction between gaseous hydrochloric acid and ammonia (base), forming white ammonium chloride `{{Acids and bases}}`{=mediawiki} In chemistry, an acid--base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid--base theories, for example, Brønsted--Lowry acid--base theory. Their importance becomes apparent in analyzing acid--base reactions for gaseous or liquid species, or when acid or base character may be somewhat less apparent. The first of these concepts was provided by the French chemist Antoine Lavoisier, around 1776. It is important to think of the acid--base reaction models as theories that complement each other. For example, the current Lewis model has the broadest definition of what an acid and base are, with the Brønsted--Lowry theory being a subset of what acids and bases are, and the Arrhenius theory being the most restrictive. ## Acid--base definitions {#acidbase_definitions} ### Historic development {#historic_development} The concept of an acid--base reaction was first proposed in 1754 by Guillaume-François Rouelle, who introduced the word \"base\" into chemistry to mean a substance which reacts with an acid to give it solid form (as a salt). Bases are mostly bitter in nature. #### Lavoisier\'s oxygen theory of acids {#lavoisiers_oxygen_theory_of_acids} The first scientific concept of acids and bases was provided by Lavoisier in around 1776. Since Lavoisier\'s knowledge of strong acids was mainly restricted to oxoacids, such as `{{chem2\|HNO3}}`{=mediawiki} (nitric acid) and `{{chem2\|H2SO4}}`{=mediawiki} (sulfuric acid), which tend to contain central atoms in high oxidation states surrounded by oxygen, and since he was not aware of the true composition of the hydrohalic acids (HF, HCl, HBr, and HI), he defined acids in terms of their containing oxygen, which in fact he named from Greek words meaning \"acid-former\" (`{{ety\|el\|''ὀξύς'' (oxys)\|acid, sharp\|\|''γεινομαι'' (geinomai)\|engender}}`{=mediawiki}). The Lavoisier definition held for over 30 years, until the 1810 article and subsequent lectures by Sir Humphry Davy in which he proved the lack of oxygen in hydrogen sulfide (`{{chem2\|H2S}}`{=mediawiki}), hydrogen telluride (`{{chem2\|H2Te}}`{=mediawiki}), and the hydrohalic acids. However, Davy failed to develop a new theory, concluding that \"acidity does not depend upon any particular elementary substance, but upon peculiar arrangement of various substances\". One notable modification of oxygen theory was provided by Jöns Jacob Berzelius, who stated that acids are oxides of nonmetals while bases are oxides of metals. #### Liebig\'s hydrogen theory of acids {#liebigs_hydrogen_theory_of_acids} In 1838, Justus von Liebig proposed that an acid is a hydrogen-containing compound whose hydrogen can be replaced by a metal. This redefinition was based on his extensive work on the chemical composition of organic acids, finishing the doctrinal shift from oxygen-based acids to hydrogen-based acids started by Davy. Liebig\'s definition, while completely empirical, remained in use for almost 50 years until the adoption of the Arrhenius definition. ### Arrhenius definition {#arrhenius_definition} The first modern definition of acids and bases in molecular terms was devised by Svante Arrhenius. A hydrogen theory of acids, it followed from his 1884 work with Friedrich Wilhelm Ostwald in establishing the presence of ions in aqueous solution and led to Arrhenius receiving the Nobel Prize in Chemistry in 1903. As defined by Arrhenius: - An Arrhenius acid is a substance that ionises in water to form hydrogen cations (`{{chem2\|H+}}`{=mediawiki}); that is, an acid increases the concentration of H^+^ ions in an aqueous solution. This causes the protonation of water, or the creation of the hydronium (`{{chem2\|H3O+}}`{=mediawiki}) ion.`{{refn\|group=note\|More recent [[IUPAC]] recommendations now suggest the newer term "hydronium"<ref>{{cite journal \|last1=Murray \|first1=Kermit K. \|last2=Boyd \|first2=Robert K. \|last3=Eberlin \|first3=Marcos N. \|last4=Langley \|first4=G. John \|last5=Li \|first5=Liang \|last6=Naito \|first6=Yasuhide \|date=June 2013 \|orig-year=2006 \|title=Standard definition of terms relating to mass spectrometry recommendations \|journal=[[Pure and Applied Chemistry]] \|volume=85 \|issue=7 \|pages=1515–1609 \|doi=10.1351/PAC-REC-06-04-06\|s2cid=98095406 \|url=https://www.degruyter.com/downloadpdf/j/pac.2013.85.issue-7/pac-rec-06-04-06/pac-rec-06-04-06.pdf \|archive-url=https://ghostarchive.org/archive/20221009/https://www.degruyter.com/downloadpdf/j/pac.2013.85.issue-7/pac-rec-06-04-06/pac-rec-06-04-06.pdf \|archive-date=2022-10-09 \|url-status=live}} (In this document, there is no reference to deprecation of "oxonium", which is also still accepted, as it remains in the IUPAC Gold book, but rather reveals preference for the term "Hydronium".)</ref> be used in favor of the older accepted term "oxonium"<ref name="iupac_gold">{{cite book \|title= IUPAC Compendium of Chemical Terminology (interactive version) \|edition= 2.3.3 \|year= 2014 \|publisher= International Union of Pure and Applied Chemistry \|doi= 10.1351/goldbook.O04379 \|access-date= 9 May 2007 \|url= http://goldbook.iupac.org/terms/view/O04379 \|article= oxonium ylides}}</ref> to illustrate reaction mechanisms such as those defined in the Brønsted–Lowry and solvent system definitions more clearly, with the Arrhenius definition serving as a simple general outline of acid–base character.<ref name="miessler_165"/>}}`{=mediawiki} Thus, in modern times, the symbol `{{chem2\|H+}}`{=mediawiki} is interpreted as a shorthand for `{{chem2\|H3O+}}`{=mediawiki}, because it is now known that a bare proton does not exist as a free species in aqueous solution. This is the species which is measured by pH indicators to measure the acidity or basicity of a solution. - An Arrhenius base is a substance that dissociates in water to form hydroxide (`{{chem2\|OH-}}`{=mediawiki}) ions; that is, a base increases the concentration of `{{chem2\|OH-}}`{=mediawiki} ions in an aqueous solution. The Arrhenius definitions of acidity and alkalinity are restricted to aqueous solutions and are not valid for most non-aqueous solutions, and refer to the concentration of the solvent ions. Under this definition, pure `{{chem2\|H2SO4}}`{=mediawiki} and HCl dissolved in toluene are not acidic, and molten NaOH and solutions of calcium amide in liquid ammonia are not alkaline. This led to the development of the Brønsted--Lowry theory and subsequent Lewis theory to account for these non-aqueous exceptions. The reaction of an acid with a base is called a neutralization reaction. The products of this reaction are a salt and water. $\text{acid} \ + \ \text{base} \ \longrightarrow \ \text{salt} \ + \ \text{water}$ In this traditional representation an acid--base neutralization reaction is formulated as a double-replacement reaction. For example, the reaction of hydrochloric acid (HCl) with sodium hydroxide (NaOH) solutions produces a solution of sodium chloride (NaCl) and some additional water molecules. $\ce{HCl_{(aq)} {} + NaOH_{(aq)} -> NaCl_{(aq)} {} + H2O}$ The modifier (aq) in this equation was implied by Arrhenius, rather than included explicitly. It indicates that the substances are dissolved in water. Though all three substances, HCl, NaOH and NaCl are capable of existing as pure compounds, in aqueous solutions they are fully dissociated into the aquated ions `{{chem2\|H+, Cl-, Na+}}`{=mediawiki} and `{{chem2\|OH-}}`{=mediawiki}. #### Example: Baking powder {#example_baking_powder} Baking powder is used to cause the dough for breads and cakes to \"rise\" by creating millions of tiny carbon dioxide bubbles. Baking powder is not to be confused with baking soda, which is sodium bicarbonate (`{{chem2\|NaHCO3}}`{=mediawiki}). Baking powder is a mixture of baking soda (sodium bicarbonate) and acidic salts. The bubbles are created because, when the baking powder is combined with water, the sodium bicarbonate and acid salts react to produce gaseous carbon dioxide. Whether commercially or domestically prepared, the principles behind baking powder formulations remain the same. The acid--base reaction can be generically represented as shown: $\ce{NaHCO3 + H+ -> Na+ + CO2 + H2O}$ The real reactions are more complicated because the acids are complicated. For example, starting with sodium bicarbonate and monocalcium phosphate (`{{chem2\|Ca(H2PO4)2}}`{=mediawiki}), the reaction produces carbon dioxide by the following stoichiometry: $\ce{14 NaHCO3 + 5 Ca(H2PO4)2 -> 14 CO2 + Ca5(PO4)3OH + 7 Na2HPO4 + 13 H2O}$ A typical formulation (by weight) could call for 30% sodium bicarbonate, 5--12% monocalcium phosphate, and 21--26% sodium aluminium sulfate. Alternately, a commercial baking powder might use sodium acid pyrophosphate as one of the two acidic components instead of sodium aluminium sulfate. Another typical acid in such formulations is cream of tartar (`{{chem2\|KC4H5O6}}`{=mediawiki}), a derivative of tartaric acid. ### Brønsted--Lowry definition {#brønstedlowry_definition} The Brønsted--Lowry definition, formulated in 1923, independently by Johannes Nicolaus Brønsted in Denmark and Martin Lowry in England, is based upon the idea of protonation of bases through the deprotonation of acids -- that is, the ability of acids to \"donate\" hydrogen cations (`{{chem2\|H+}}`{=mediawiki})`{{snd}}`{=mediawiki} otherwise known as protons`{{snd}}`{=mediawiki} to bases, which \"accept\" them. An acid--base reaction is, thus, the removal of a proton from the acid and its addition to the base. The removal of a proton from an acid produces its conjugate base, which is the acid with a proton removed. The reception of a proton by a base produces its conjugate acid, which is the base with a proton added. Unlike the previous definitions, the Brønsted--Lowry definition does not refer to the formation of salt and solvent, but instead to the formation of conjugate acids and conjugate bases, produced by the transfer of a proton from the acid to the base. In this approach, acids and bases are fundamentally different in behavior from salts, which are seen as electrolytes, subject to the theories of Debye, Onsager, and others. An acid and a base react not to produce a salt and a solvent, but to form a new acid and a new base. The concept of neutralization is thus absent. Brønsted--Lowry acid--base behavior is formally independent of any solvent, making it more all-encompassing than the Arrhenius model. The calculation of pH under the Arrhenius model depended on alkalis (bases) dissolving in water (aqueous solution). The Brønsted--Lowry model expanded what could be pH tested using insoluble and soluble solutions (gas, liquid, solid). The general formula for acid--base reactions according to the Brønsted--Lowry definition is: $\ce{HA + B -> BH+ + A-}$ where HA represents the acid, B represents the base, `{{chem2\|BH+}}`{=mediawiki} represents the conjugate acid of B, and `{{chem2\|A-}}`{=mediawiki} represents the conjugate base of HA. For example, a Brønsted--Lowry model for the dissociation of hydrochloric acid (HCl) in aqueous solution would be the following: $\underset{\text{acid}}{\ce{HCl_{\,}}} \ + \ \underset{\text{base}}{\ce{H2O}} \quad \ce{<=>} \quad \underset{\text{conjugate } \atop \text{acid }}{\ce{H3O+}} \ + \underset{\text{conjugate} \atop \text{base}}{\ce{Cl_{\,}-}}$ The removal of `{{chem2\|H+}}`{=mediawiki} from the `{{chem2\|HCl}}`{=mediawiki} produces the chloride ion, `{{chem2\|Cl-}}`{=mediawiki}, the conjugate base of the acid. The addition of `{{chem2\|H+}}`{=mediawiki} to the `{{chem2\|H2O}}`{=mediawiki} (acting as a base) forms the hydronium ion, `{{chem2\|H3O+}}`{=mediawiki}, the conjugate acid of the base. Water is amphoteric`{{snd}}`{=mediawiki} that is, it can act as both an acid and a base. The Brønsted--Lowry model explains this, showing the dissociation of water into low concentrations of hydronium and hydroxide ions: $\ce{H2O + H2O <=> H3O+ + OH-}$ This equation is demonstrated in the image below: Here, one molecule of water acts as an acid, donating an `{{chem2\|H+}}`{=mediawiki} and forming the conjugate base, `{{chem2\|OH-}}`{=mediawiki}, and a second molecule of water acts as a base, accepting the `{{chem2\|H+}}`{=mediawiki} ion and forming the conjugate acid, `{{chem2\|H3O+}}`{=mediawiki}. As an example of water acting as an acid, consider an aqueous solution of pyridine, `{{chem2\|C5H5N}}`{=mediawiki}. $\ce{C5H5N + H2O <=> [C5H5NH]+ + OH-}$ In this example, a water molecule is split into a hydrogen cation, which is donated to a pyridine molecule, and a hydroxide ion. In the Brønsted--Lowry model, the solvent does not necessarily have to be water, as is required by the Arrhenius Acid--Base model. For example, consider what happens when acetic acid, `{{chem2\|CH3COOH}}`{=mediawiki}, dissolves in liquid ammonia. $\ce{CH3COOH + NH3 <=> NH4+ + CH3COO-}$ An `{{chem2\|H+}}`{=mediawiki} ion is removed from acetic acid, forming its conjugate base, the acetate ion, `{{chem2\|CH3COO-}}`{=mediawiki}. The addition of an `{{chem2\|H+}}`{=mediawiki} ion to an ammonia molecule of the solvent creates its conjugate acid, the ammonium ion, `{{chem2\|NH4+}}`{=mediawiki}. The Brønsted--Lowry model calls hydrogen-containing substances (like `{{chem2\|HCl}}`{=mediawiki}) acids. Thus, some substances, which many chemists considered to be acids, such as `{{chem2\|SO3}}`{=mediawiki} or `{{chem2\|BCl3}}`{=mediawiki}, are excluded from this classification due to lack of hydrogen. Gilbert N. Lewis wrote in 1938, \"To restrict the group of acids to those substances that contain hydrogen interferes as seriously with the systematic understanding of chemistry as would the restriction of the term oxidizing agent to substances containing oxygen.\" Furthermore, `{{chem2\|KOH}}`{=mediawiki} and `{{chem2\|KNH2}}`{=mediawiki} are not considered Brønsted bases, but rather salts containing the bases `{{chem2\|OH(-)}}`{=mediawiki} and `{{chem\|NH\|2\|−}}`{=mediawiki}. ### Lewis definition {#lewis_definition} The hydrogen requirement of Arrhenius and Brønsted--Lowry was removed by the Lewis definition of acid--base reactions, devised by Gilbert N. Lewis in 1923, in the same year as Brønsted--Lowry, but it was not elaborated by him until 1938. Instead of defining acid--base reactions in terms of protons or other bonded substances, the Lewis definition defines a base (referred to as a Lewis base) to be a compound that can donate an electron pair, and an acid (a Lewis acid) to be a compound that can receive this electron pair. For example, boron trifluoride, `{{chem2\|BF3}}`{=mediawiki} is a typical Lewis acid. It can accept a pair of electrons as it has a vacancy in its octet. The fluoride ion has a full octet and can donate a pair of electrons. Thus $\ce{BF3 + F- -> BF4-}$ is a typical Lewis acid, Lewis base reaction. All compounds of group 13 elements with a formula `{{chem2\|AX3}}`{=mediawiki} can behave as Lewis acids. Similarly, compounds of group 15 elements with a formula `{{chem2\|DY3}}`{=mediawiki}, such as amines, `{{chem2\|NR3}}`{=mediawiki}, and phosphines, `{{chem2\|PR3}}`{=mediawiki}, can behave as Lewis bases. Adducts between them have the formula `{{chem2\|X3A←DY3}}`{=mediawiki} with a dative covalent bond, shown symbolically as ←, between the atoms A (acceptor) and D (donor). Compounds of group 16 with a formula `{{chem2\|DX2}}`{=mediawiki} may also act as Lewis bases; in this way, a compound like an ether, `{{chem2\|R2O}}`{=mediawiki}, or a thioether, `{{chem2\|R2S}}`{=mediawiki}, can act as a Lewis base. The Lewis definition is not limited to these examples. For instance, carbon monoxide acts as a Lewis base when it forms an adduct with boron trifluoride, of formula `{{chem2\|F3B←CO}}`{=mediawiki}. Adducts involving metal ions are referred to as co-ordination compounds; each ligand donates a pair of electrons to the metal ion. The reaction $\ce{[Ag(H2O)4]+ + 2 NH3 -> [Ag(NH3)2]+ + 4 H2O}$ can be seen as an acid--base reaction in which a stronger base (ammonia) replaces a weaker one (water). The Lewis and Brønsted--Lowry definitions are consistent with each other since the reaction $\ce{H+ + OH- <=> H2O}$ is an acid--base reaction in both theories. ### Solvent system definition {#solvent_system_definition} One of the limitations of the Arrhenius definition is its reliance on water solutions. Edward Curtis Franklin studied the acid--base reactions in liquid ammonia in 1905 and pointed out the similarities to the water-based Arrhenius theory. Albert F.O. Germann, working with liquid phosgene, `{{chem\|COCl\|2}}`{=mediawiki}, formulated the solvent-based theory in 1925, thereby generalizing the Arrhenius definition to cover aprotic solvents. Germann pointed out that in many solutions, there are ions in equilibrium with the neutral solvent molecules: - solvonium ions: a generic name for positive ions. These are also sometimes called solvo-acids; when protonated solvent, they are lyonium ions. - solvate ions: a generic name for negative ions. These are also sometimes called solve-bases; when deprotonated solvent, they are lyate ions. For example, water and ammonia undergo such dissociation into hydronium and hydroxide, and ammonium and amide, respectively: $\begin{align} \ce{2 H2O} & \ce{\, <=> H3O+ + OH-} \\[4pt] \ce{2 NH3} & \ce{\, <=> NH4+ + NH2-} \end{align}$ Some aprotic systems also undergo such dissociation, such as dinitrogen tetroxide into nitrosonium and nitrate,{{#tag:ref\\|Pure N~2~O~4~ does not undergo such dissolution. However, it becomes electrically conductive when mixed with a polarized compound, which is believed to correspond with the establishment of such an equilibrium.\\|group=note}} antimony trichloride into dichloroantimonium and tetrachloroantimonate, and phosgene into chlorocarboxonium and chloride: $\begin{align} \ce{N2O4} & \ce{\, <=> NO+ + NO3-} \\[4pt] \ce{2 SbCl3} & \ce{\, <=> SbCl2+ + SbCl4-} \\[4pt] \ce{COCl2} & \ce{\, <=> COCl+ + Cl-} \end{align}$ A solute that causes an increase in the concentration of the solvonium ions and a decrease in the concentration of solvate ions is defined as an acid. A solute that causes an increase in the concentration of the solvate ions and a decrease in the concentration of the solvonium ions is defined as a base. Thus, in liquid ammonia, `{{chem2\|KNH2}}`{=mediawiki} (supplying `{{chem2\|NH2-}}`{=mediawiki}) is a strong base, and `{{chem2\|NH4NO3}}`{=mediawiki} (supplying `{{chem2\|NH4+}}`{=mediawiki}) is a strong acid. In liquid sulfur dioxide (`{{chem2\|SO2}}`{=mediawiki}), thionyl compounds (supplying `{{chem2\|SO(2+)}}`{=mediawiki}) behave as acids, and sulfites (supplying `{{chem2\|SO3(2-)}}`{=mediawiki}) behave as bases. The non-aqueous acid--base reactions in liquid ammonia are similar to the reactions in water: $\begin{align} \underset{\text{base}}{\ce{2 NaNH2}} + \underset{\text{amphiphilic} \atop \text{amide}}{\ce{Zn(NH2)2}} &\longrightarrow \ce{Na2[Zn(NH2)4]} \\[4pt] \underset{\text{acid}}{\ce{2 NH4I}} \ + \ \ce{Zn(NH2)2} &\longrightarrow \ce{[Zn(NH3)4]I2} \end{align}$ Nitric acid can be a base in liquid sulfuric acid: $\underset{\text{base}}{\ce{HNO3}} + \ce{2 H2SO4 -> NO2+ + H3O+ + 2 HSO4-}$ The unique strength of this definition shows in describing the reactions in aprotic solvents; for example, in liquid `{{chem2\|N2O4}}`{=mediawiki}: $\underset{\text{base}}{\ce{AgNO3}} + \underset{\text{acid}}{\ce{NOCl_{\ }}} \longrightarrow \underset{\text{solvent}}{\ce{N2O4}} + \underset{\text{salt}}{\ce{AgCl_{\ }}}$ Because the solvent system definition depends on the solute as well as on the solvent itself, a particular solute can be either an acid or a base depending on the choice of the solvent: `{{chem2\|HClO4}}`{=mediawiki} is a strong acid in water, a weak acid in acetic acid, and a weak base in fluorosulfonic acid; this characteristic of the theory has been seen as both a strength and a weakness, because some substances (such as `{{chem2\|SO3}}`{=mediawiki} and `{{chem2\|NH3}}`{=mediawiki}) have been seen to be acidic or basic on their own right. On the other hand, solvent system theory has been criticized as being too general to be useful. Also, it has been thought that there is something intrinsically acidic about hydrogen compounds, a property not shared by non-hydrogenic solvonium salts. ### Lux--Flood definition {#luxflood_definition} This acid--base theory was a revival of the oxygen theory of acids and bases proposed by German chemist Hermann Lux in 1939, further improved by Håkon Flood c. 1947 and is still used in modern geochemistry and electrochemistry of molten salts. This definition describes an acid as an oxide ion (`{{chem2\|O(2-)}}`{=mediawiki}) acceptor and a base as an oxide ion donor. For example: $\begin{array}{ccccl} _\text{(base)} & & _\text{(acid)} \\[4pt] \ce{MgO} &+& \ce{CO2} &\longrightarrow& \ce{MgCO3} \\[4pt] \ce{CaO} &+& \ce{SiO2} &\longrightarrow& \ce{CaSiO3} \\[4pt] \ce{NO3-} &+& \ce{S2O7^2-} \!\! &\longrightarrow& \ce{NO2+ + 2 SO4^2-} \end{array}$ This theory is also useful in the systematisation of the reactions of noble gas compounds, especially the xenon oxides, fluorides, and oxofluorides. ### Usanovich definition {#usanovich_definition} Mikhail Usanovich developed a general theory that does not restrict acidity to hydrogen-containing compounds, but his approach, published in 1938, was even more general than Lewis theory. Usanovich\'s theory can be summarized as defining an acid as anything that accepts negative species or donates positive ones, and a base as the reverse. This defined the concept of redox (oxidation-reduction) as a special case of acid--base reactions. Some examples of Usanovich acid--base reactions include: $\begin{array}{ccccll} _\text{(base)} & & _\text{(acid)} \\[4pt] \ce{Na2O} &+& \ce{SO3} &\longrightarrow& \ce{2Na+ {} + \ SO4^2-} & \text{(species exchanged: } \ce{O^2-} \text{anion)} \\[4pt] \ce{3(NH4)2S} &+& \ce{Sb2S5} &\longrightarrow& \ce{6 NH4+ {} + \ 2 SbS4^3-} & \text{(species exchanged: } \ce{3 S^2-} \text{ anions)} \\[4pt] \ce{2Na} &+& \ce{Cl2} &\longrightarrow& \ce{2 Na+ {} + \ 2 Cl-} & \text{(species exchanged: 2 electrons)} \end{array}$ ## Rationalizing the strength of Lewis acid--base interactions {#rationalizing_the_strength_of_lewis_acidbase_interactions} ### HSAB theory {#hsab_theory} In 1963, Ralph Pearson proposed a qualitative concept known as the Hard and Soft Acids and Bases principle. later made quantitative with help of Robert Parr in 1984. \'Hard\' applies to species that are small, have high charge states, and are weakly polarizable. \'Soft\' applies to species that are large, have low charge states and are strongly polarizable. Acids and bases interact, and the most stable interactions are hard--hard and soft--soft. This theory has found use in organic and inorganic chemistry. ### ECW model {#ecw_model} The ECW model created by Russell S. Drago is a quantitative model that describes and predicts the strength of Lewis acid base interactions, `{{math\|−Δ''H''}}`{=mediawiki}. The model assigned `{{mvar\|E}}`{=mediawiki} and `{{mvar\|C}}`{=mediawiki} parameters to many Lewis acids and bases. Each acid is characterized by an `{{math\|''E''<sub>A</sub>}}`{=mediawiki} and a `{{math\|''C''<sub>A</sub>}}`{=mediawiki}. Each base is likewise characterized by its own `{{math\|''E''<sub>B</sub>}}`{=mediawiki} and `{{math\|''C''<sub>B</sub>}}`{=mediawiki}. The `{{mvar\|E}}`{=mediawiki} and `{{mvar\|C}}`{=mediawiki} parameters refer, respectively, to the electrostatic and covalent contributions to the strength of the bonds that the acid and base will form. The equation is $-\Delta H = E_{\rm A}E_{\rm B} + C_{\rm A}C_{\rm B} + W$ The `{{mvar\|W}}`{=mediawiki} term represents a constant energy contribution for acid--base reaction such as the cleavage of a dimeric acid or base. The equation predicts reversal of acids and base strengths. The graphical presentations of the equation show that there is no single order of Lewis base strengths or Lewis acid strengths. ## Acid--base equilibrium {#acidbase_equilibrium} The reaction of a strong acid with a strong base is essentially a quantitative reaction. For example, $\ce{HCl_{(aq)} {} + Na(OH)_{(aq)} -> H2O + NaCl_{(aq)} }$ In this reaction both the sodium and chloride ions are spectators as the neutralization reaction, $\ce{H + OH- -> H2O}$ does not involve them. With weak bases addition of acid is not quantitative because a solution of a weak base is a buffer solution. A solution of a weak acid is also a buffer solution. When a weak acid reacts with a weak base an equilibrium mixture is produced. For example, adenine, written as AH, can react with a hydrogen phosphate ion, `{{chem2\|HPO4(2-)}}`{=mediawiki}. $\ce{AH + HPO4^2- <=> A- + H2PO4-}$ The equilibrium constant for this reaction can be derived from the acid dissociation constants of adenine and of the dihydrogen phosphate ion. $\begin{align} \left[\ce{A-}\right] \! \left[\ce{H+}\right] &= K_{a1}\bigl[\ce{AH}\bigr] \\[4pt] \left[\ce{HPO4^2-}\right] \! \left[\ce{H+}\right] &= K_{a2}\left[\ce{H2PO4-}\right] \end{align}$ The notation \[X\] signifies \"concentration of X\". When these two equations are combined by eliminating the hydrogen ion concentration, an expression for the equilibrium constant, `{{mvar\|K}}`{=mediawiki} is obtained. $\left[\ce{A-}\right] \! \left[\ce{H2PO4-}\right] = K \bigl[\ce{AH}\bigr] \! \left[\ce{HPO4^2-}\right]; \quad K = \frac{K_{a1}}{K_{a2}}$ ## Acid--alkali reaction {#acidalkali_reaction} An acid--alkali reaction is a special case of an acid--base reaction, where the base used is also an alkali. When an acid reacts with an alkali salt (a metal hydroxide), the product is a metal salt and water. Acid--alkali reactions are also neutralization reactions. In general, acid--alkali reactions can be simplified to : $\ce{OH_{(aq)}- + H+_{(aq)} -> H2O}$ by omitting spectator ions. Acids are in general pure substances that contain hydrogen cations (`{{chem2\|H+}}`{=mediawiki}) or cause them to be produced in solutions. Hydrochloric acid (`{{chem2\|HCl}}`{=mediawiki}) and sulfuric acid (`{{chem2\|H2SO4}}`{=mediawiki}) are common examples. In water, these break apart into ions: : \\begin{align} \\ce{HCl} &\\longrightarrow \\ce{H\_{(aq)}+ {} + Cl\_{(aq)}- } \\\\\[4pt\] \\ce{H2SO4} &\\longrightarrow \\ce{H\_{(aq)}+ {} + HSO4\_{\\,(aq)}- } \\end{align} The alkali breaks apart in water, yielding dissolved hydroxide ions: : $\ce{NaOH -> Na^+_{(aq)} {} + OH_{(aq)}- }$.	2025-06-20T00:00:00
3,044	Amphisbaena	The amphisbaena (`{{IPAc-en\|ˌ\|æ\|m\|f\|ɪ\|s\|ˈ\|b\|ɛ\|ɪ\|n\|ə}}`{=mediawiki}, `{{IPAc-en\|ˌ\|æ\|m\|f\|ɪ\|s\|ˈ\|b\|aɪ\|n\|ə}}`{=mediawiki}, or `{{IPAc-en\|ˌ\|æ\|m\|f\|ɪ\|s\|ˈ\|b\|iː\|n\|ə}}`{=mediawiki}, plural: amphisbaenae; ἀμφίσβαινα) is a mythological, ant-eating serpent with a head at each end. The name of the creature is alternatively written amphisbaina, amphisbene, amphisboena, amphisbona, amphista, amfivena, amphivena, or anphivena, and is also known as the \"Mother of Ants\".`{{citation needed lead\|date=January 2014}}`{=mediawiki} Its name comes from the Greek words `{{Transliteration\|el\|amphis}}`{=mediawiki}, meaning \"both ways\", and `{{Transliteration\|el\|bainein}}`{=mediawiki}, meaning \"to go\".`{{citation needed lead\|date=January 2014}}`{=mediawiki} ## Mythology According to Lucan, the amphisbaena was spawned from the blood that dripped from the Gorgon Medusa\'s head as Perseus flew over the Libyan Desert with her head in his hand: in Pharsalia (IX, 719), the Roman poet names it along with other serpents that Cato\'s army encountered in Libya. Amphisbaena fed on the corpses left behind. Although it is a legendary creature, it has been referred to by various Greek and Latin authors, scientists as well as poets: Nicander, Lucan, Pliny the Elder, Isidore of Seville and later Thomas Browne, the last of whom debunked its existence ( book three chapter XV). Modern poets are John Milton, Alexander Pope, Percy Bysshe Shelley, Alfred Tennyson, Aimé Césaire, A. E. Housman and Allen Mandelbaum. ## Appearance thumb\\|upright=1.2\\|A 15th-century amphisbaena (a two-headed beast) on a misericord in Buckinghamshire These early descriptions of the amphisbaena depict a venomous, dual-headed snakelike creature. However, medieval and later drawings often show it with two or more scaled feet, particularly chicken feet, and feathered wings. Some`{{Who\|date=January 2015}}`{=mediawiki} even depict it as a horned, dragon-like creature with a serpent-headed tail and small, round ears, while others have both \"necks\" of equal size so that it cannot be determined which is the rear head. Many descriptions`{{by whom\|date=October 2016}}`{=mediawiki} of the amphisbaena say its eyes glow like candles or lightning, but the poet Nicander, the first to speak about it, described it as \"always dull of eye\". He also wrote: \"From either end protrudes a blunt chin; each is far from each other.\" Nicander\'s account seems to be referring to a group of real lizards what is today called the Amphisbaenia, after the legendary creature, because their tail truncates in a manner that vaguely resembles the head. ## Habitat The amphisbaena is said to make its home in the desert. ## Folk medicine {#folk_medicine} In ancient times, the supposedly dangerous amphisbaena had many uses in the art of folk medicine and other magical remedies. Pliny notes that expecting women wearing a live amphisbaena around their necks would have safe pregnancies (Naturalis historia XXX, 128); however, if one\'s goal was to cure ailments such as arthritis or the common cold, one should wear only its skin (Naturalis historia XXX, 85): lumberjacks suffering from cold weather on the job could nail its carcass or skin to a tree to keep warm, while in the process allowing the tree to be felled more easily. By eating the meat of the amphisbaena, one could supposedly attract many lovers of the opposite sex, and slaying one during the full moon could give power to one who is pure of heart and mind. ^\[primary\ reference\ needed\]^ ## Origins In The Book of Beasts, T.H. White suggests that the creature derives from sightings of the worm lizards of the same name. But it is the other way around. These creatures are found in the Mediterranean countries where many of these legends originated. The Códice Casanatense (c. 1540), a Portuguese book describing the areas the Portuguese had visited, includes an illustration of the flora and fauna of India. One of the animals shown is a two-headed snake (conjoined twin snakes), with one head on each end, much like an amphisbaena. The image is captioned, \"two headed snakes of India are harmless\". It is possible a sighting of an animal like this was the origin of the amphisbaena, or that the Greek mythological creature is used, as well as others, to literarily embellish the description of an exotic country. ## In literature and other media {#in_literature_and_other_media} In Parmenides\'s poem there seems to be an allusion to the amphisbaena. Mortals are said to \"stray two-headed, for perplexity in their own breasts directs their mind astray\". In Dante\'s Inferno, the amphisbaena is listed as one of the types of reptiles that torment thieves in the seventh bolgia. In John Milton\'s Paradise Lost, after the Fall and the return of Satan to Hell, some of the fallen angelic host are transformed into the amphisbaena, to represent the animal by which the Fall was caused, i.e. a snake. Amphisbaena appears in some editions of the tabletop roleplaying game Dungeons & Dragons. Amphisbaena has appeared in several video games as an enemy or boss monster, including La-Mulana and Bravely Second: End Layer. A creature called Amphisbaena appears in the games Castlevania: Symphony of the Night and Portrait of Ruin but bears little resemblance to other renditions of the creature, appearing as an eyeless 4-legged reptile with the upper body of a human woman sprouting from its long tail instead of a double-headed serpent. In the 1984 animated film Gallavants, an amphisbaena (called a \"Vanterviper\" in the film) appears as a minor antagonist. The two heads, a red one named Edil and a blue one called Fice, frequently disagree and argue, and sing a song about their miserable plight. The amphisbaena is mentioned in The Last Wish, from The Witcher series by Andrzej Sapkowski, while protagonist Geralt of Rivia recalls past events. The amphisbaena was endangering the region of Kovir until the beast was slain by Geralt\'s hand. Amphisbaena is referenced in RWBY, an animated web series created by Monty Oum, in the form of an evil creature called Grimm. Of the different Grimm, the amphisbaena appears to be the King Taijitu, a two-headed snake or serpent. The king\'s name references the taijitu, a symbol or diagram in Chinese philosophy representing Taiji in both its monist and dualist aspects. The Grimm\'s coloration visually symbolizes the taijitu, with one head and body section black and the opposite side white. The amphisbaena appears in the Rise of the Teenage Mutant Ninja Turtles episode \"Battle Nexus: New York\". This version is one of the known champions of the Battle Nexus. Big Mama had Michelangelo and Meat Sweats compete to feed each of its heads in order to satisfy the amphisbaena. They managed to work together to pull it off. Brandon Sanderson\'s novel Skyward has a character whose name is Arturo Mendez. His call sign is amphisbaena. Beyblade has a character named Enrique whose bit beast (ancient spirits contained within spinning tops) is named Amphilyon. It takes the form of a medieval amphisbaena with bat wings. The primary antagonist of Elden Ring: Shadow of the Erdtree, Messmer the Impaler, is conjoined with a winged amphisbaena. ## Use as a Proverb {#use_as_a_proverb} The amphisbaena appears also in the saying \"to the amphisbaena, Perseus is good\" which can have various meanings depending in the connotation in which it is used. However, one main meaning lies in the connection between Perseus and the creation of the amphisbaena. Though created out of the violent murder of Medusa by Perseus, it shows that the creation will always see the creator in a positive light.	2025-06-20T00:00:00
3,045	Amyl alcohol	Amyl alcohols are alcohols with the formula C~5~H~11~OH. Eight are known. A mixture of amyl alcohols (also called amyl alcohol) can be obtained from fusel alcohol. Amyl alcohol is used as a solvent and in esterification, by which is produced amyl acetate and other products. The name amyl alcohol without further specification applies to the normal (straight-chain) form, 1-pentanol. : {\\| class=\"wikitable sortable\" \\|+Amyl alcohol isomers \\|- ! Common name !! Structure !! Type !! IUPAC name !! Boiling point (°C) \\|- \\| 1-pentanol\ or normal amyl alcohol \\| \\| primary \\| Pentan-1-ol \\| 138.5 \\|- \\| 2-methyl-1-butanol\ or active amyl alcohol \\| \\| primary \\| 2-Methylbutan-1-ol \\| 128.7 \\|- \\| 3-methyl-1-butanol\ or isoamyl alcohol\ or isopentyl alcohol \\| \\| primary \\| 3-Methylbutan-1-ol \\| 131.2 \\|- \\| 2,2-dimethyl-1-propanol\ or neopentyl alcohol \\| \\| primary \\| 2,2-Dimethylpropan-1-ol \\| 113.1 \\|- \\| 2-pentanol\ or sec-amyl alcohol\ or methyl (n) propyl carbinol \\| \\| secondary \\| Pentan-2-ol \\| 118.8 \\|- \\| 3-methyl-2-butanol\ or sec-isoamyl alcohol\ or methyl isopropyl carbinol \\| \\| secondary \\| 3-Methylbutan-2-ol \\| 113.6 \\|- \\| 3-Pentanol \\| \\| secondary \\| Pentan-3-ol \\| 115.3 \\|- \\| 2-methyl-2-butanol\ or tert-amyl alcohol \\| \\| tertiary \\| 2-Methylbutan-2-ol \\| 102 \\|} Three of these alcohols, 2-methyl-1-butanol, 2-pentanol, and 3-methyl-2-butanol (methyl isopropyl carbinol), contain stereocenters, and are therefore chiral and optically active. The most important amyl alcohol is isoamyl alcohol, the chief one generated by fermentation in the production of alcoholic beverages and a constituent of fusel oil. The other amyl alcohols may be obtained synthetically.	2025-06-20T00:00:00
3,046	Amyl nitrite	Amyl nitrite is a chemical compound with the formula C~5~H~11~ONO. A variety of isomers are known, but they all feature an amyl group attached to the nitrite functional group. The alkyl group (the amyl in this case) is unreactive and the chemical and biological properties are mainly due to the nitrite group. Like other alkyl nitrites, amyl nitrite is bioactive in mammals, being a vasodilator, which is the basis of its use as a prescription medicine. As an inhalant, it also has a psychoactive effect, which has led to its recreational use, with its smell being described as that of old socks or dirty feet. It was first documented in 1844 and came into medical use in 1867. ## Uses - Amyl nitrite was historically employed medically to treat heart diseases as well as angina. - Amyl nitrite was sometimes used as an antidote for cyanide poisoning. It was thought to act as an oxidant, to induce the formation of methemoglobin. Methemoglobin in turn can sequester cyanide as cyanomethemoglobin. However, it has been replaced by hydroxocobalamin which had better efficacy, and the use of amyl nitrite has been found to be ineffective and unscientific. - Trace amounts are added to some perfumes. - It is also used recreationally as an inhalant drug that induces a brief euphoric state, and when combined with other intoxicant stimulant drugs such as cocaine or MDMA, the euphoric state intensifies and is prolonged. Once some stimulative drugs wear off, a common side effect is a period of depression or anxiety, colloquially called a \"come down\"; amyl nitrite is sometimes used to combat these negative after-effects. This effect, combined with its dissociative effects, has led to its use as a recreational drug `{{xref\|(see: [[Poppers]])}}`{=mediawiki}. ## Nomenclature The term \"amyl nitrite\" encompasses several isomers. In older literature, the common non-systematic name amyl was often used for the pentyl group, where the amyl group is a linear or normal (n) alkyl group, and the resulting amyl nitrite would have the structural formula CH~3~(CH~2~)~3~CH~2~ONO, also referred to as n-amyl nitrite. A common form of amyl nitrite is the isomer with the formula (CH~3~)~2~CHCH~2~CH~2~ONO, which may be more specifically referred to as isoamyl nitrite. The similarly named amyl nitrate has very different properties. At the same time, isopropyl nitrite has a similar structure and similar uses (also called \'poppers\') but with worse side-effects. Amyl nitrite is sometimes referred to colloquially as banapple gas. ## Synthesis and reactions {#synthesis_and_reactions} Alkyl nitrites are prepared by the reaction of alcohols with nitrous acid: : ROH + HONO → RONO + H~2~O, where R = alkyl group The reaction is called esterification. Synthesis of alkyl nitrites is, in general, straightforward and can be accomplished in home laboratories. A common procedure includes the dropwise addition of concentrated sulfuric acid to a cooled mixture of an aqueous sodium nitrite solution and an alcohol. The intermediately-formed stoichiometric mixture of nitrogen dioxide and nitric oxide then converts the alcohol to the alkyl nitrite, which, due to its low density, will form an upper layer that can be easily decanted from the reaction mixture. Isoamyl nitrite decomposes in the presence of base to give nitrite salts and the isoamyl alcohol: : C~5~H~11~ONO + NaOH → C~5~H~11~OH + NaNO~2~ Amyl nitrite, like other alkyl nitrites, reacts with carbanions to give oximes. Amyl nitrites are also useful as reagents in a modification of the Sandmeyer reaction. The reaction of the alkyl nitrite with an aromatic amine in a halogenated solvent produces a radical aromatic species, this then frees a halogen atom from the solvent. For the synthesis of aryl iodides diiodomethane is used, whereas bromoform is the solvent of choice for the synthesis of aryl bromides. ## Physiological effects {#physiological_effects} Amyl nitrite, in common with other alkyl nitrites, is a potent vasodilator; it expands blood vessels, resulting in lowering of the blood pressure. Amyl nitrite may be used during cardiovascular stress testing in patients with suspected hypertrophic cardiomyopathy to cause vasodilation and thereby reduce afterload and provoke obstruction of blood flow towards the aorta from the ventricle by increasing the pressure gradient, thereby causing left ventricular outflow obstruction. Alkyl nitrites are a source of nitric oxide, which signals for relaxation of the involuntary muscles. Physical effects include decrease in blood pressure, headache, flushing of the face, increased heart rate, dizziness, and relaxation of involuntary muscles, especially the blood vessel walls and the internal and external anal sphincter. There are no withdrawal symptoms. Overdose symptoms include nausea, vomiting, hypotension, hypoventilation, shortness of breath, and fainting. The effects set in very quickly, typically within a few seconds and disappear within a few minutes. Amyl nitrite may also intensify the experience of synesthesia. Amyl nitrite, when given as a medication for patients with angina, can also be administered as an ampule. The ampule is put in a gauze pad and then inhaled by the patient during an angina attack and repeated every fifteen minutes. However, oral dosing of amyl nitrite is ineffective due to poor absorption and extensive hepatic metabolism. Amyl nitrite has been widely replaced by nitroglycerin for the treatment of acute angina. ## Toxicity Although there are case reports of life-threatening toxicity involving unusually large amounts, typical inhaled doses of amyl nitrite are considered relatively safe. However, liquid amyl nitrite is highly toxic when ingested because of the dangerously high concentration it causes in the blood. Regardless of the form or route of administration, acute toxicity principally results when the nitrite oxidizes a significant proportion of hemoglobin in the blood without oxygen, forming methemoglobin, which cannot carry oxygen. Severe poisoning cases will progress to methemoglobinemia, characterized by a blue-brown discoloration under the skin which could be mistaken for cyanosis. Treatment with oxygen and intravenous methylene blue frustrates visual confirmation further as methylene blue itself is, as its name suggests, a blue dye; the patient\'s changes in different shades of blue notwithstanding, it is an effective antidote by way of catalyzing the production of the enzyme responsible for reducing the methemoglobin in the blood back to hemoglobin. The discoloration does mean that regular near-infrared--based pulse oximetry becomes useless. More fundamentally, blood gas analysis on the whole has limited effectiveness, as the increased methemoglobin level increases the oxygen binding affinity of regular hemoglobin. Therefore, the measurement of actual ratios and levels of methemoglobin and hemoglobin must accompany any blood gas partial pressure sample in these cases. ## In popular culture {#in_popular_culture} The Columbo episode titled \"Troubled Waters\" (1974--1975) features amyl nitrite inhaled by the antagonist Hayden Danziger -- played by Robert Vaughn -- to help him feign a heart attack for his alibi. However, the episode consistently refers to the substance incorrectly as amyl nitrate. The 1978 Derek Jarman film Jubilee features a character credited as \"Amyl Nitrite\", although in the film itself the character is \"Amyl Nitrate\". The title of the 1993 song \"Animal Nitrate\" by English band Suede is a pun on amyl nitrite, referencing its recreational use, although singer Brett Anderson has said the song has more to do with other drugs like ecstasy and cocaine. In the 1999 film Fight Club, the character Chloe, a terminally ill woman, mentions having a collection of amyl nitrite while openly discussing her unfulfilled desires at a cancer support group. The punk band Amyl and the Sniffers reference recreational use of amyl nitrite in their name. The Hunter S. Thompson book Fear and Loathing in Las Vegas sees amyl nitrite as one of the many drugs Raoul Duke packs for the trip to Las Vegas, taking about two dozen ampules of it with him and usually justifying its usage by him and Dr. Gonzo to other people around them by claiming it is for angina. In Season 1, Episode 9 of Bob\'s Burgers, \"Spaghetti Western and Meatballs\", Gene guesses amyl nitrite for the A in the ABS program near the end of the episode.	2025-06-20T00:00:00
3,054	Alpha helix	An alpha helix (or α-helix) is a sequence of amino acids in a protein that are twisted into a coil (a helix). The alpha helix is the most common structural arrangement in the secondary structure of proteins. It is also the most extreme type of local structure, and it is the local structure that is most easily predicted from a sequence of amino acids. The alpha helix has a right-handed helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group of the amino acid that is four residues earlier in the protein sequence. ## Other names {#other_names} The alpha helix is also commonly called a: - Pauling--Corey--Branson α-helix (from the names of three scientists who described its structure) - 3.6~13~-helix because there are 3.6 amino acids in one ring, with 13 atoms being involved in the ring formed by the hydrogen bond (starting with amidic hydrogen and ending with carbonyl oxygen) ## Discovery In the early 1930s, William Astbury showed that there were drastic changes in the X-ray fiber diffraction of moist wool or hair fibers upon significant stretching. The data suggested that the unstretched fibers had a coiled molecular structure with a characteristic repeat of ≈5.1 Å. Astbury initially proposed a linked-chain structure for the fibers. He later joined other researchers (notably the American chemist Maurice Huggins) in proposing that: - the unstretched protein molecules formed a helix (which he called the α-form) - the stretching caused the helix to uncoil, forming an extended state (which he called the β-form). Although incorrect in their details, Astbury\'s models of these forms were correct in essence and correspond to modern elements of secondary structure, the α-helix and the β-strand (Astbury\'s nomenclature was kept), which were developed by Linus Pauling, Robert Corey and Herman Branson in 1951 (see below); that paper showed both right- and left-handed helices, although in 1960 the crystal structure of myoglobin showed that the right-handed form is the common one. Hans Neurath was the first to show that Astbury\'s models could not be correct in detail, because they involved clashes of atoms. Neurath\'s paper and Astbury\'s data inspired H. S. Taylor, Maurice Huggins and Bragg and collaborators to propose models of keratin that somewhat resemble the modern α-helix. Two key developments in the modeling of the modern α-helix were: the correct bond geometry, thanks to the crystal structure determinations of amino acids and peptides and Pauling\'s prediction of planar peptide bonds; and his relinquishing of the assumption of an integral number of residues per turn of the helix. The pivotal moment came in the early spring of 1948, when Pauling caught a cold and went to bed. Being bored, he drew a polypeptide chain of roughly correct dimensions on a strip of paper and folded it into a helix, being careful to maintain the planar peptide bonds. After a few attempts, he produced a model with physically plausible hydrogen bonds. Pauling then worked with Corey and Branson to confirm his model before publication. In 1954, Pauling was awarded his first Nobel Prize \"for his research into the nature of the chemical bond and its application to the elucidation of the structure of complex substances\" (such as proteins), prominently including the structure of the α-helix. ## Structure ### Geometry and hydrogen bonding {#geometry_and_hydrogen_bonding} The amino acids in an α-helix are arranged in a right-handed helical structure where each amino acid residue corresponds to a 100° turn in the helix (i.e., the helix has 3.6 residues per turn), and a translation of 1.5 Å along the helical axis. Dunitz describes how Pauling\'s first article on the theme in fact shows a left-handed helix, the enantiomer of the true structure. Short pieces of left-handed helix sometimes occur with a large content of achiral glycine amino acids, but are unfavorable for the other normal, biological `{{small\|L}}`{=mediawiki}-amino acids. The pitch of the alpha-helix (the vertical distance between consecutive turns of the helix) is 5.4 Å, which is the product of 1.5 and 3.6. The most important thing is that the N-H group of one amino acid forms a hydrogen bond with the C=O group of the amino acid four residues earlier; this repeated i + 4 → i hydrogen bonding is the most prominent characteristic of an α-helix. Official international nomenclature specifies two ways of defining α-helices, rule 6.2 in terms of repeating φ, ψ torsion angles (see below) and rule 6.3 in terms of the combined pattern of pitch and hydrogen bonding. The α-helices can be identified in protein structure using several computational methods, such as DSSP (Define Secondary Structure of Protein). Similar structures include the 3~10~ helix (i + 3 → i hydrogen bonding) and the π-helix (i + 5 → i hydrogen bonding). The α-helix can be described as a 3.6~13~ helix, since the i + 4 spacing adds three more atoms to the H-bonded loop compared to the tighter 3~10~ helix, and on average, 3.6 amino acids are involved in one ring of α-helix. The subscripts refer to the number of atoms (including the hydrogen) in the closed loop formed by the hydrogen bond. Residues in α-helices typically adopt backbone (φ, ψ) dihedral angles around (−60°, −45°), as shown in the image at right. In more general terms, they adopt dihedral angles such that the ψ dihedral angle of one residue and the φ dihedral angle of the next residue sum to roughly −105°. As a consequence, α-helical dihedral angles, in general, fall on a diagonal stripe on the Ramachandran diagram (of slope −1), ranging from (−90°, −15°) to (−70°, −35°). For comparison, the sum of the dihedral angles for a 3~10~ helix is roughly −75°, whereas that for the π-helix is roughly −130°. The general formula for the rotation angle Ω per residue of any polypeptide helix with trans isomers is given by the equation : 1 − 4 cos^2^ `{{sfrac\|''φ'' + ''ψ''\|2}}`{=mediawiki}}} The α-helix is tightly packed; there is almost no free space within the helix. The amino-acid side-chains are on the outside of the helix, and point roughly \"downward\" (i.e., toward the N-terminus), like the branches of an evergreen tree (Christmas tree effect). This directionality is sometimes used in preliminary, low-resolution electron-density maps to determine the direction of the protein backbone. ### Stability Helices observed in proteins can range from four to over forty residues long, but a typical helix contains about ten amino acids (about three turns). In general, short polypeptides do not exhibit much α-helical structure in solution, since the entropic cost associated with the folding of the polypeptide chain is not compensated for by a sufficient amount of stabilizing interactions. In general, the backbone hydrogen bonds of α-helices are considered slightly weaker than those found in β-sheets, and are readily attacked by the ambient water molecules. However, in more hydrophobic environments such as the plasma membrane, or in the presence of co-solvents such as trifluoroethanol (TFE), or isolated from solvent in the gas phase, oligopeptides readily adopt stable α-helical structure. Furthermore, crosslinks can be incorporated into peptides to conformationally stabilize helical folds. Crosslinks stabilize the helical state by entropically destabilizing the unfolded state and by removing enthalpically stabilized \"decoy\" folds that compete with the fully helical state. It has been shown that α-helices are more stable, robust to mutations and designable than β-strands in natural proteins, and also in artificially designed proteins. ### Visualization The three most popular ways of visualizing the alpha-helical secondary structure of oligopeptide sequences are (1) a helical wheel, (2) a wenxiang diagram, and (3) a helical net. Each of these can be visualized with various software packages and web servers. To generate a small number of diagrams, Heliquest can be used for helical wheels, and NetWheels can be used for helical wheels and helical nets. To programmatically generate a large number of diagrams, helixvis can be used to draw helical wheels and wenxiang diagrams in the R and Python programming languages. ## Experimental determination {#experimental_determination} Since the α-helix is defined by its hydrogen bonds and backbone conformation, the most detailed experimental evidence for α-helical structure comes from atomic-resolution X-ray crystallography such as the example shown at right. It is clear that all the backbone carbonyl oxygens point downward (toward the C-terminus) but splay out slightly, and the H-bonds are approximately parallel to the helix axis. Protein structures from NMR spectroscopy also show helices well, with characteristic observations of nuclear Overhauser effect (NOE) couplings between atoms on adjacent helical turns. In some cases, the individual hydrogen bonds can be observed directly as a small scalar coupling in NMR. There are several lower-resolution methods for assigning general helical structure. The NMR chemical shifts (in particular of the C^α^, C^β^ and C′) and residual dipolar couplings are often characteristic of helices. The far-UV (170--250 nm) circular dichroism spectrum of helices is also idiosyncratic, exhibiting a pronounced double minimum at around 208 and 222 nm. Infrared spectroscopy is rarely used, since the α-helical spectrum resembles that of a random coil (although these might be discerned by, e.g., hydrogen-deuterium exchange). Finally, cryo electron microscopy is now capable of discerning individual α-helices within a protein, although their assignment to residues is still an active area of research. Long homopolymers of amino acids often form helices if soluble. Such long, isolated helices can also be detected by other methods, such as dielectric relaxation, flow birefringence, and measurements of the diffusion constant. In stricter terms, these methods detect only the characteristic prolate (long cigar-like) hydrodynamic shape of a helix, or its large dipole moment. ## Amino-acid propensities {#amino_acid_propensities} Different amino-acid sequences have different propensities for forming α-helical structure. Alanine, uncharged glutamate, leucine, charged arginine, methionine and charged lysine have especially high helix-forming propensities, whereas proline and glycine have poor helix-forming propensities. Proline either breaks or kinks a helix, both because it cannot donate an amide hydrogen bond (because it has none) and because its sidechain interferes sterically with the backbone of the preceding turn`{{snd}}`{=mediawiki} inside a helix, which forces a bend of about 30° in the helix\'s axis. However, proline is often the first residue of a helix, presumably due to its structural rigidity. At the other extreme, glycine also tends to disrupt helices because its high conformational flexibility makes it entropically expensive to adopt the relatively constrained α-helical structure. ### Table of standard amino acid alpha-helical propensities {#table_of_standard_amino_acid_alpha_helical_propensities} Estimated differences in free energy change, Δ(ΔG), estimated in kcal/mol per residue in an α-helical configuration, relative to alanine arbitrarily set as zero. Higher numbers (more positive free energy changes) are less favoured. Significant deviations from these average numbers are possible, depending on the identities of the neighbouring residues. : {\\| class=\"wikitable sortable\" \\|+Differences in free energy change per residue !rowspan=2\\| Amino acid !rowspan=2 class=\"unsortable\"\\| 3-\ letter !rowspan=2 class=\"unsortable\"\\| 1-\ letter !colspan=2\\| Helical penalty \\|- !kcal/mol !kJ/mol \\|- \\| Alanine \\| Ala \\| A \\| 0.00 kcal/mol \\|- \\| Arginine \\| Arg \\| R \\| 0.21 kcal/mol \\|- \\| Asparagine \\| Asn \\| N \\| 0.65 kcal/mol \\|- \\| Aspartic acid \\| Asp \\| D \\| 0.69 kcal/mol \\|- \\| Cysteine \\| Cys \\| C \\| 0.68 kcal/mol \\|- \\| Glutamic acid \\| Glu \\| E \\| 0.40 kcal/mol \\|- \\| Glutamine \\| Gln \\| Q \\| 0.39 kcal/mol \\|- \\| Glycine \\| Gly \\| G \\| 1.00 kcal/mol \\|- \\| Histidine \\| His \\| H \\| 0.61 kcal/mol \\|- \\| Isoleucine \\| Ile \\| I \\| 0.41 kcal/mol \\|- \\| Leucine \\| Leu \\| L \\| 0.21 kcal/mol \\|- \\| Lysine \\| Lys \\| K \\| 0.26 kcal/mol \\|- \\| Methionine \\| Met \\| M \\| 0.24 kcal/mol \\|- \\| Phenylalanine \\| Phe \\| F \\| 0.54 kcal/mol \\|- \\| Proline \\| Pro \\| P \\| 3.16 kcal/mol \\|- \\| Serine \\| Ser \\| S \\| 0.50 kcal/mol \\|- \\| Threonine \\| Thr \\| T \\| 0.66 kcal/mol \\|- \\| Tryptophan \\| Trp \\| W \\| 0.49 kcal/mol \\|- \\| Tyrosine \\| Tyr \\| Y \\| 0.53 kcal/mol \\|- \\| Valine \\| Val \\| V \\| 0.61 kcal/mol \\|} ## Dipole moment {#dipole_moment} A helix has an overall dipole moment due to the aggregate effect of the individual microdipoles from the carbonyl groups of the peptide bond pointing along the helix axis. The effects of this macrodipole are a matter of some controversy. α-helices often occur with the N-terminal end bound by a negatively charged group, sometimes an amino acid side chain such as glutamate or aspartate, or sometimes a phosphate ion. Some regard the helix macrodipole as interacting electrostatically with such groups. Others feel that this is misleading and it is more realistic to say that the hydrogen bond potential of the free NH groups at the N-terminus of an α-helix can be satisfied by hydrogen bonding; this can also be regarded as set of interactions between local microdipoles such as `{{nowrap\|1=C=O···H−N}}`{=mediawiki}. ## Coiled coils {#coiled_coils} Coiled-coil α helices are highly stable forms in which two or more helices wrap around each other in a \"supercoil\" structure. Coiled coils contain a highly characteristic sequence motif known as a heptad repeat, in which the motif repeats itself every seven residues along the sequence (amino acid residues, not DNA base-pairs). The first and especially the fourth residues (known as the a and d positions) are almost always hydrophobic; the fourth residue is typically leucine`{{snd}}`{=mediawiki} this gives rise to the name of the structural motif called a leucine zipper, which is a type of coiled-coil. These hydrophobic residues pack together in the interior of the helix bundle. In general, the fifth and seventh residues (the e and g positions) have opposing charges and form a salt bridge stabilized by electrostatic interactions. Fibrous proteins such as keratin or the \"stalks\" of myosin or kinesin often adopt coiled-coil structures, as do several dimerizing proteins. A pair of coiled-coils`{{snd}}`{=mediawiki} a four-helix bundle`{{snd}}`{=mediawiki} is a very common structural motif in proteins. For example, it occurs in human growth hormone and several varieties of cytochrome. The Rop protein, which promotes plasmid replication in bacteria, is an interesting case in which a single polypeptide forms a coiled-coil and two monomers assemble to form a four-helix bundle. ## Facial arrangements {#facial_arrangements} The amino acids that make up a particular helix can be plotted on a helical wheel, a representation that illustrates the orientations of the constituent amino acids (see the article for leucine zipper for such a diagram). Often in globular proteins, as well as in specialized structures such as coiled-coils and leucine zippers, an α-helix will exhibit two \"faces\"`{{snd}}`{=mediawiki} one containing predominantly hydrophobic amino acids oriented toward the interior of the protein, in the hydrophobic core, and one containing predominantly polar amino acids oriented toward the solvent-exposed surface of the protein. Changes in binding orientation also occur for facially-organized oligopeptides. This pattern is especially common in antimicrobial peptides, and many models have been devised to describe how this relates to their function. Common to many of them is that the hydrophobic face of the antimicrobial peptide forms pores in the plasma membrane after associating with the fatty chains at the membrane core. ## Larger-scale assemblies {#larger_scale_assemblies} Myoglobin and hemoglobin, the first two proteins whose structures were solved by X-ray crystallography, have very similar folds made up of about 70% α-helix, with the rest being non-repetitive regions, or \"loops\" that connect the helices. In classifying proteins by their dominant fold, the Structural Classification of Proteins database maintains a large category specifically for all-α proteins. Hemoglobin then has an even larger-scale quaternary structure, in which the functional oxygen-binding molecule is made up of four subunits. ## Functional roles {#functional_roles} ### DNA binding {#dna_binding} α-Helices have particular significance in DNA binding motifs, including helix-turn-helix motifs, leucine zipper motifs and zinc finger motifs. This is because of the convenient structural fact that the diameter of an α-helix is about 12 Å including an average set of sidechains, about the same as the width of the major groove in B-form DNA, and also because coiled-coil (or leucine zipper) dimers of helices can readily position a pair of interaction surfaces to contact the sort of symmetrical repeat common in double-helical DNA. An example of both aspects is the transcription factor Max (see image at left), which uses a helical coiled coil to dimerize, positioning another pair of helices for interaction in two successive turns of the DNA major groove. ### Membrane spanning {#membrane_spanning} α-Helices are also the most common protein structure element that crosses biological membranes (transmembrane protein), presumably because the helical structure can satisfy all backbone hydrogen-bonds internally, leaving no polar groups exposed to the membrane if the sidechains are hydrophobic. Proteins are sometimes anchored by a single membrane-spanning helix, sometimes by a pair, and sometimes by a helix bundle, most classically consisting of seven helices arranged up-and-down in a ring such as for rhodopsins (see image at right) and other G protein--coupled receptors (GPCRs). The structural stability between pairs of α-Helical transmembrane domains rely on conserved membrane interhelical packing motifs, for example, the Glycine-xxx-Glycine (or small-xxx-small) motif. ### Mechanical properties {#mechanical_properties} α-Helices under axial tensile deformation, a characteristic loading condition that appears in many alpha-helix-rich filaments and tissues, results in a characteristic three-phase behavior of stiff-soft-stiff tangent modulus. Phase I corresponds to the small-deformation regime during which the helix is stretched homogeneously, followed by phase II, in which alpha-helical turns break mediated by the rupture of groups of H-bonds. Phase III is typically associated with large-deformation covalent bond stretching. ## Dynamical features {#dynamical_features} Alpha-helices in proteins may have low-frequency accordion-like motion as observed by the Raman spectroscopy and analyzed via the quasi-continuum model. Helices not stabilized by tertiary interactions show dynamic behavior, which can be mainly attributed to helix fraying from the ends. ## Helix--coil transition {#helixcoil_transition} Homopolymers of amino acids (such as polylysine) can adopt α-helical structure at low temperature that is \"melted out\" at high temperatures. This helix--coil transition was once thought to be analogous to protein denaturation. The statistical mechanics of this transition can be modeled using an elegant transfer matrix method, characterized by two parameters: the propensity to initiate a helix and the propensity to extend a helix. ## In art {#in_art} At least five artists have made explicit reference to the α-helix in their work: Julie Newdoll in painting and Julian Voss-Andreae, Bathsheba Grossman, Byron Rubin, and Mike Tyka in sculpture. San Francisco area artist Julie Newdoll, who holds a degree in microbiology with a minor in art, has specialized in paintings inspired by microscopic images and molecules since 1990. Her painting \"Rise of the Alpha Helix\" (2003) features human figures arranged in an α helical arrangement. According to the artist, \"the flowers reflect the various types of sidechains that each amino acid holds out to the world\". This same metaphor is also echoed from the scientist\'s side: \"β sheets do not show a stiff repetitious regularity but flow in graceful, twisting curves, and even the α-helix is regular more in the manner of a flower stem, whose branching nodes show the influence of environment, developmental history, and the evolution of each part to match its own idiosyncratic function.\" Julian Voss-Andreae is a German-born sculptor with degrees in experimental physics and sculpture. Since 2001 Voss-Andreae creates \"protein sculptures\" based on protein structure with the α-helix being one of his preferred objects. Voss-Andreae has made α-helix sculptures from diverse materials including bamboo and whole trees. A monument Voss-Andreae created in 2004 to celebrate the memory of Linus Pauling, the discoverer of the α-helix, is fashioned from a large steel beam rearranged in the structure of the α-helix. The 10 ft, bright-red sculpture stands in front of Pauling\'s childhood home in Portland, Oregon. Ribbon diagrams of α-helices are a prominent element in the laser-etched crystal sculptures of protein structures created by artist Bathsheba Grossman, such as those of insulin, hemoglobin, and DNA polymerase. Byron Rubin is a former protein crystallographer now professional sculptor in metal of proteins, nucleic acids, and drug molecules`{{snd}}`{=mediawiki} many of which featuring α-helices, such as subtilisin, human growth hormone, and phospholipase A2. Mike Tyka is a computational biochemist at the University of Washington working with David Baker. Tyka has been making sculptures of protein molecules since 2010 from copper and steel, including ubiquitin and a potassium channel tetramer.	2025-06-20T00:00:00
3,058	Armageddon	`{{Christian Eschatology}}`{=mediawiki} Armageddon (`{{IPAc-en\|ˌ\|ɑːr\|m\|ə\|ˈ\|g\|ɛ\|d\|ən\|audio=LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-armageddon.wav}}`{=mediawiki} `{{respell\|AR\|mə\|GHED\|ən}}`{=mediawiki}; Ἁρμαγεδών}}; Armagedōn; from Har Məgīddō) is the prophesied gathering of armies for a battle during the end times, according to the Book of Revelation in the New Testament of the Christian Bible. Armageddon is variously interpreted as either a literal or a symbolic location, although the term has since become more often used in a generic sense to refer to any end-of-the-world scenario. In Islamic theology, Armageddon is also mentioned in Hadith as the Greatest Armageddon or Al-Malhama Al-Kubra (the great battle). The \"mount\" of Megiddo in northern Israel is not actually a mountain, but a tell (a mound or hill created by many generations of people living and rebuilding at the same spot) on which ancient forts were built to guard the Via Maris, an ancient trade route linking Egypt with the northern empires of Syria, Anatolia and Mesopotamia. Megiddo was the location of various ancient battles, including one in the 15th century BC and one in 609 BC. The nearby modern Megiddo is a kibbutz in the Kishon River area. ## Etymology The word Armageddon appears only once in the Greek New Testament, in Revelation 16:16. The word is a Greek transliteration of the Hebrew har məgīddō (rtl=yes). Har means \"a mountain\" or \"a range of hills\". This is a shortened form of harar meaning \"to loom up; a mountain\". Məgīddō refers to a fortification made by King Ahab that dominated the Plain of Jezreel. Its name means \"place of crowds\". Adam Clarke wrote in his Bible commentary (1817) on Revelation 16:16: > Armageddon -- The original of this word has been variously formed, and variously translated. It is הר־מגדון har-megiddon, \"the mount of the assembly;\" or חרמה גדהון chormah gedehon, \"the destruction of their army;\" or it is הר־מגדו har-megiddo, \"Mount Megiddo.\" ## Christianity Megiddo is mentioned twelve times in the Old Testament, ten times in reference to the ancient city of Megiddo, and twice with reference to \"the plain of Megiddo\", most probably simply meaning \"the plain next to the city\". None of these Old Testament passages describes the city of Megiddo as being associated with any particular prophetic beliefs. The one New Testament reference to the city of Armageddon found in `{{bibleverse\|Revelation\|16:16}}`{=mediawiki} makes no specific mention of any armies being predicted to one day gather in this city, either, but instead seems to predict only that \"they (will gather) the kings together to \... Armageddon\". The text does however seem to imply, based on the text from the earlier passage of Revelation 16:14, that the purpose of this gathering of kings in the \"place called Armageddon\" is \"for the war of the great day of God, the Almighty\". Because of the seemingly highly symbolic and even cryptic language of this one New Testament passage, some Christian scholars conclude that Mount Armageddon must be an idealized location. R. J. Rushdoony says, \"There are no mountains of Megiddo, only the Plains of Megiddo. This is a deliberate destruction of the vision of any literal reference to the place.\" Other scholars, including C. C. Torrey, Kline and Jordan, argue that the word is derived from the Hebrew moed (rtl=yes), meaning \"assembly\". Thus, \"Armageddon\" would mean \"Mountain of Assembly\", which Jordan says is \"a reference to the assembly at Mount Sinai, and to its replacement, Mount Zion\". Most traditions interpret this Bible prophecy to be symbolic of the progression of the world toward the \"great day of God, the Almighty\" in which God pours out his just and holy wrath against unrepentant sinners led by Satan, in a literal end-of-the-world final confrontation. \'Armageddon\' is the symbolic name given to this event based on scripture references regarding divine obliteration of God\'s enemies. The hermeneutical method supports this position by referencing Judges 4 and 5 where God miraculously destroys the enemy of their elect, Israel, at Megiddo. Christian scholar William Hendriksen writes: `{{blockquote\|For this cause, Har Magedon is the symbol of every battle in which, when the need is greatest and believers are oppressed, the Lord suddenly reveals His power in the interest of His distressed people and defeats the enemy. When Sennacherib's 185,000 are slain by the Angel of Jehovah, that is a shadow of the final Har-Magedon. When God grants a little handful of Maccabees a glorious victory over an enemy which far outnumbers it, that is a type of Har-Magedon. But the real, the great, the final Har Magedon coincides with the time of Satan’s little season. Then the world, under the leadership of Satan, anti-Christian government, and anti-Christian religion – the dragon, the beast, and the false prophet – is gathered against the Church for the final battle, and the need is greatest; when God's children, oppressed on every side, cry for help; then suddenly, Christ will appear on the clouds of glory to deliver his people; that is Har-Magedon.<ref>[[William Hendriksen]], ''More Than Conquerors'', 163.</ref>}}`{=mediawiki} ### Dispensationalism In his discussion of Armageddon, J. Dwight Pentecost has devoted a chapter to the subject, \"The Campaign of Armageddon\", in which he discusses it as a campaign and not a specific battle, which will be fought in the Middle East. Pentecost writes: `{{blockquote\|It has been held commonly that the battle of Armageddon is an isolated event transpiring just prior to the second advent of Christ to the earth. The extent of this great movement in which God deals with "the kings of the earth and of the whole world"<ref>Rev. 16:14</ref> will not be seen unless it is realized that the "battle of that great day of God Almighty"<ref>{{bibleverse\|\|Revelation\|16:14\|NKJV}}</ref> is not an isolated battle, but rather a campaign that extends over the last half of the tribulation period. The Greek word "polemo", translated "battle" in Revelation 16:14, signifies a war or campaign, while "machē" signifies a battle, and sometimes even single combat. This distinction is observed by Trench (see [[Richard Chenevix Trench\|Richard C. Trench]], ''New Testament Synonyms'', pp. 301–32) and is followed by Thayer (see [[Joseph Henry Thayer]], ''Greek-English Lexicon of the New Testament'', p. 528) and Vincent (see Marvin R. Vincent, ''Word Studies in the New Testament'', II, 541). The use of the word ''polemos'' (campaign) in Revelation 16:14 signifies that God views the events culminating in the gathering at Armageddon at the second advent as one connected campaign.\|Pentecost, p. 340}}`{=mediawiki} Pentecost then discusses the location of this campaign, and mentions the \"hill of Megiddo\" and other geographic locations such as \"the valley of Jehoshaphat\" and \"the valley of the passengers\", \"Lord coming from Edom or Idumea, south of Jerusalem, when he returns from the judgment\"; and Jerusalem itself. Pentecost further describes the area involved: `{{blockquote\|This wide area would cover the entire land of Israel and this campaign, with all its parts, would confirm what Ezekiel pictures when he says the invaders will 'cover the land'.<ref>{{bibleverse\|\|Ezekiel\|38:9–16\|NKJV}}</ref> This area would conform to the extent pictured by [[John of Patmos\|John]] in Revelation 14:20.<ref>{{bibleverse\|\|Revelation\|14:20\|NKJV}}</ref>}}`{=mediawiki} Pentecost then outlines the biblical time period for this campaign to occur and with further arguments concludes that it must take place with the 70th week of Daniel. The invasion of Israel by the Northern Confederacy \"will bring the Beast and his armies to the defense of Israel as her protector\". He then uses Daniel to further clarify his thinking. Again, events are listed by Pentecost in his book: 1. \"The movement of the campaign begins when the King of the South moves against the Beast--False Prophet coalition, which takes place \'at the time of the end\'.\" 2. The King of the South gets in battle with the North King and the Northern Confederacy. Jerusalem is destroyed as a result of this attack, and, in turn, the armies of the Northern Confederacy are destroyed. 3. \"The full armies of the Beast move into Israel and shall conquer all that territory. Edom, Moab, and Ammon alone escape.\" 4. \"\... a report that causes alarm is brought to the Beast\" 5. \"The Beast moves his headquarters into the land of Israel and assembles his armies there.\" 6. \"It is there that his destruction will come.\" After the destruction of the Beast at the Second Coming of Jesus, the promised Kingdom is set up, in which Jesus and the saints will rule for a thousand years. Satan is then loosed \"for a season\" and goes out to deceive the nations, specifically Gog and Magog. The army mentioned attacks the saints in the New Jerusalem, they are defeated by a judgment of fire coming down from heaven, and then comes the Great White Throne judgment, which includes all of those through the ages and these are cast into the Lake of Fire, which event is also known as the \"second death\" and Gehenna, not to be confused with Hell, which is Satan\'s domain. Pentecost describes this as follows: ### Jehovah\'s Witnesses {#jehovahs_witnesses} Jehovah\'s Witnesses believe that Armageddon is the means by which God will fulfill his purpose for the Earth to be populated with happy healthy humans who will be free from sin and death. They teach that the armies of heaven will eradicate all who oppose the Kingdom of God, wiping out all wicked humans on Earth, only leaving righteous mankind. They believe that the gathering of all of the nations of the earth refers to the uniting of the world\'s political powers, as a gradual process which began in 1914 and was later seen in manifestations such as the League of Nations and the United Nations following the First and Second World Wars.`{{full citation needed\|reason=author? publisher? year?\|date=June 2022}}`{=mediawiki} These political powers are said to be influenced by Satan and they are disgusting in that they stand in the place of God\'s kingdom before men as the only hope of mankind. Babylon the Great is interpreted as being the world empire of false religions, and it will be destroyed by the beast just prior to Armageddon.`{{full citation needed\|reason=what is this, a book? who wrote it and when?\|date=June 2022}}`{=mediawiki} Witnesses believe that after all other religions have been destroyed, the governments of the world will turn their attention to destroying Jehovah\'s Witnesses, provoking God to intervene and precipitating Armageddon. Jehovah\'s Witnesses teach that the armies of heaven, led by Jesus, will then destroy all forms of human government and then Jesus, along with a selected 144,000 humans, will rule Earth for 1,000 years. They believe that Satan and his demons will be bound for that period, unable to influence mankind. After the 1,000 years are ended, and the second resurrection has taken place, Satan is released and allowed to tempt the perfect human race one last time. Those who follow Satan will be destroyed, along with him, leaving the earth, and humankind at peace with God forever, free from sin and death. The religion\'s current teaching on Armageddon originated in 1925 with former Watch Tower Society president J. F. Rutherford, who based his interpretations on passages that are found in the books of Exodus, Jeremiah, Ezekiel and Psalms as well as additional passages that are found in the books of Samuel, Kings and Chronicles. The doctrine marked a further break from the teachings of the Watch Tower Society\'s founder Charles Taze Russell, who for decades had taught that the final war would be an anarchistic struggle for domination on earth. Tony Wills, the author of a historical study of Jehovah\'s Witnesses, wrote that Rutherford seemed to relish his descriptions of how completely the wicked would be destroyed at Armageddon, dwelling at great length on prophecies of destruction. He stated that towards the close of his ministry, Rutherford allocated about half the space that was available in The Watchtower magazines to discussions about Armageddon. ### Seventh-day Adventist {#seventh_day_adventist} The teachings of the Seventh-day Adventist Church state that the terms \"Armageddon\", \"Day of the Lord\" and \"The Second Coming of Christ\" all describe the same event.`{{verify source\|reason=A conference by itself is not a [[WP:V\|verifiable]] source. Are we actually citing conference proceedings here, or something else?\|date=June 2022}}`{=mediawiki} Seventh-day Adventists further teach that the current religious movements taking place in the world are setting the stage for Armageddon, and they are concerned by an anticipated unity between spiritualism, American Protestantism and Roman Catholicism. A further teaching in Seventh-day Adventist theology is that the events of Armageddon will leave the earth desolate for the duration of the millennium.`{{full citation needed\|date=June 2022}}`{=mediawiki} They teach that the righteous will be taken to heaven while the rest of humanity will be destroyed, leaving Satan with no one to tempt and effectively \"bound\". The final re-creation of a \"new heaven and a new earth\"; then follows the millennium. ### Christadelphians For Christadelphians, Armageddon marks the \"great climax of history when the nations would be gathered together \'into a place called in the Hebrew tongue Armageddon\', and the judgment on them would herald the setting up of the Kingdom of God.\" ## Baháʼí Faith {#baháʼí_faith} From Baháʼí literature, a number of interpretations of the expectations surrounding the Battle of Armageddon may be inferred, three of them being associated with events surrounding the World Wars. The first interpretation deals with a series of tablets written by Bahá\'u\'lláh, founder of the Baháʼí Faith, to be sent to various kings and rulers. The second, and best-known one, relates to events near the end of World War I involving General Allenby and the Battle of Megiddo (1918) wherein World Powers are said to have drawn soldiers from many parts of the world to engage in battle at Megiddo. In winning this battle Allenby also prevented the Ottomans from killing \'Abdu\'l-Baha, then head of the Baháʼí Faith, whom they had intended to crucify. A third interpretation reviews the overall progress of the World Wars, and the situation in the world before and after.	2025-06-20T00:00:00
3,060	Athlon	AMD Athlon is the brand name applied to a series of x86-compatible microprocessors designed and manufactured by Advanced Micro Devices. The original Athlon (now called Athlon Classic) was the first seventh-generation x86 processor and the first desktop processor to reach speeds of one gigahertz (GHz). It made its debut as AMD\'s high-end processor brand on June 23, 1999. Over the years AMD has used the Athlon name with the 64-bit Athlon 64 architecture, the Athlon II, and Accelerated Processing Unit (APU) chips targeting the Socket AM1 desktop SoC architecture, and Socket AM4 Zen (microarchitecture). The modern Zen-based Athlon with a Radeon Graphics processor was introduced in 2019 as AMD\'s highest-performance entry-level processor. ## Brand history {#brand_history} ### K7 design and development {#k7_design_and_development} The first Athlon processor was a result of AMD\'s development of K7 processors in the 1990s. AMD founder and then-CEO Jerry Sanders aggressively pursued strategic partnerships and engineering talent in the late 1990s, working to build on earlier successes in the PC market with the AMD K6 processor line. One major partnership announced in 1998 paired AMD with semiconductor giant Motorola to co-develop copper-based semiconductor technology, resulting in the K7 project being the first commercial processor to utilize copper fabrication technology. In the announcement, Sanders referred to the partnership as creating a \"virtual gorilla\" that would enable AMD to compete with Intel on fabrication capacity while limiting AMD\'s financial outlay for new facilities. The K7 design team was led by Dirk Meyer, who had previously worked as a lead engineer at DEC on multiple Alpha microprocessors. When DEC was sold to Compaq in 1998 and discontinued Alpha processor development, Sanders brought most of the Alpha design team to the K7 project. This added to the previously acquired NexGen K6 team, which already included engineers such as Vinod Dham. ### Original release {#original_release} The AMD Athlon processor launched on June 23, 1999, with general availability by August 1999. Subsequently, from August 1999 until January 2002, this initial K7 processor was the fastest x86 chip in the world. Wrote the Los Angeles Times on October 5, 1999: \"AMD has historically trailed Intel's fastest processors, but has overtaken the industry leader with the new Athlon. Analysts say the Athlon, which will be used by Compaq, IBM and other manufacturers in their most powerful PCs, is significantly faster than Intel's flagship Pentium III, which runs at a top speed of 600MHz.\" A number of features helped the chips compete with Intel. By working with Motorola, AMD had been able to refine copper interconnect manufacturing about one year before Intel, with the revised process permitting 180-nanometer processor production. The accompanying die-shrink resulted in lower power consumption, permitting AMD to increase Athlon clock speeds to the 1 GHz range. The Athlon architecture also used the EV6 bus licensed from DEC as its main system bus, allowing AMD to develop its own products without needing to license Intel\'s GTL+ bus. By the summer of 2000, AMD was shipping Athlons at high volume, and the chips were being used in systems by Gateway, Hewlett-Packard, and Fujitsu Siemens Computers among others. ### Later Athlon iterations {#later_athlon_iterations} The second-generation Athlon, the Thunderbird, debuted in 2000. AMD released the Athlon XP the following year, and the Athlon XP\'s immediate successor, the Athlon 64, was an AMD64-architecture microprocessor released in 2003. After the 2007 launch of the Phenom processors, the Athlon name was also used for mid-range processors, positioned above brands such as Sempron. The Athlon 64 X2 was released in 2005 as the first native dual-core desktop CPU designed by AMD, and the Athlon X2 was a subsequent family based on the Athlon 64 X2. Introduced in 2009, Athlon II was a dual-core family of Athlon chips. A USD\$55 low-power Athlon 200GE with a Radeon graphics processor was introduced in September 2018, sitting under the Ryzen 3 2200G. This iteration of Athlon used AMD\'s Zen-based Raven Ridge core, which in turn had debuted in Ryzen with Radeon graphics processors. With the release, AMD began using the Athlon brand name to refer to \"low-cost, high-volume products\", in a situation similar to both Intel\'s Celeron and Pentium Gold. The modern Athlon 3000G was introduced in 2019 and was positioned as AMD\'s highest-performance entry-level processor. AMD positions the Athlon against its rival, the Intel Pentium. While CPU processing performance is in the same ballpark, the Athlon 3000G uses Radeon Vega graphics, which are rated as more powerful than the Pentium\'s Intel UHD Graphics. ## Generations ### Athlon Classic (1999) {#athlon_classic_1999} The AMD Athlon processor launched on June 23, 1999, with general availability by August 1999. Subsequently, from August 1999 until January 2002, this initial K7 processor was the fastest x86 chip in the world. At launch it was, on average, 10% faster than the Pentium III at the same clock for business applications and 20% faster for gaming workloads. In commercial terms, the Athlon \"Classic\" was an enormous success. Features The Athlon Classic is a cartridge-based processor, named Slot A and similar to Intel\'s cartridge Slot 1 used for Pentium II and Pentium III. It used the same, commonly available, physical 242-pin connector used by Intel Slot 1 processors but rotated by 180 degrees to connect the processor to the motherboard. The cartridge assembly allowed the use of higher-speed cache memory modules than could be put on (or reasonably bundled with) motherboards at the time. Similar to the Pentium II and the Katmai-based Pentium III, the Athlon Classic contained 512 KB of L2 cache. This high-speed SRAM cache was run at a divisor of the processor clock and was accessed via its own 64-bit back-side bus, allowing the processor to service both front-side bus requests and cache accesses simultaneously, as compared to pushing everything through the front-side bus. The Argon-based Athlon contained 22 million transistors and measured 184 mm^2^. It was fabricated by AMD in a version of their CS44E process, a 250 nm complementary metal--oxide--semiconductor (CMOS) process with six levels of aluminium interconnect. \"Pluto\" and \"Orion\" Athlons were fabricated in a 180 nm process. The Athlon\'s CPU cache consisted of the typical two levels. Athlon was the first x86 processor with a 128 KB split level-1 cache; a 2-way associative cache separated into 2×64 KB for data and instructions (a concept from Harvard architecture). SRAM cache designs at the time were incapable of keeping up with the Athlon\'s clock scalability, resulting in compromised CPU performance in some computers. With later Athlon models, AMD would integrate the L2 cache onto the processor itself, removing dependence on external cache chips. The Slot-A Athlons were the first multiplier-locked CPUs from AMD, preventing users from setting their own desired clock speed. This was done by AMD in part to hinder CPU remarking and overclocking by resellers, which could result in inconsistent performance. Eventually a product called the \"Goldfingers device\" was created that could unlock the CPU. AMD designed the CPU with more robust x86 instruction decoding capabilities than that of K6, to enhance its ability to keep more data in-flight at once. The critical branch-predictor unit was enhanced compared to the K6. Deeper pipelining with more stages allowed higher clock speeds to be attained. Like the AMD K5 and K6, the Athlon dynamically buffered internal micro-instructions at runtime resulting from parallel x86 instruction decoding. The CPU is an out-of-order design, again like previous post-5x86 AMD CPUs. The Athlon utilizes the Alpha 21264\'s EV6 bus architecture with double data rate (DDR) technology. AMD ended its long-time handicap with floating point x87 performance by designing a super-pipelined, out-of-order, triple-issue floating-point unit (FPU). Each of its three units could independently calculate an optimal type of instructions with some redundancy, making it possible to operate on more than one floating-point instruction at once. This FPU was a huge step forward for AMD, helping compete with Intel\'s P6 FPU. The 3DNow! floating-point SIMD technology, again present, received some revisions and was renamed \"Enhanced 3DNow!\" Additions included DSP instructions and the extended MMX subset of Intel SSE. Specifications - L1-cache: 64 + 64 KB (data + instructions) - L2-cache: 512 KB, external chips on CPU module with 50%, 40% or 33% of CPU speed - MMX, 3DNow! - Slot A (EV6) - Front-side bus:100 MHz (200MT/s) - Vcore: 1.6 V (K7), 1.6--1.8 V (K75) - First release: June 23, 1999 (K7), November 29, 1999 (K75) - Clock-rate: 500--700 MHz (K7), 550--1000 MHz (K75) ### Athlon Thunderbird (2000--2001) {#athlon_thunderbird_20002001} The second-generation Athlon, the Thunderbird or T-Bird, debuted on June 4, 2000. This version of the Athlon was available in a traditional pin-grid array (PGA) format that plugged into a socket (\"Socket A\") on the motherboard, or packaged as a Slot A cartridge. The major difference between it and the Athlon Classic was cache design, with AMD adding in 256 KB of on-chip, full-speed exclusive cache. In moving to an exclusive cache design, the L1 cache\'s contents were not duplicated in the L2, increasing total cache size and functionally creating a large L1 cache with a slower region (the L2) and a fast region (the L1), making the L2 cache into basically a victim cache. With the new cache design, need for high L2 performance and size was lessened, and the simpler L2 cache was less likely to cause clock scaling and yield issues. Thunderbird also moved to a 16-way associative layout. The Thunderbird was \"cherished by many for its overclockability\" and proved commercially successful, as AMD\'s most successful product since the Am386DX-40 ten years earlier. AMD\'s new fab facility in Dresden increased production for AMD overall and put out Thunderbirds at a fast rate, with the process technology improved by a switch to copper interconnects. After several versions were released in 2000 and 2001 of the Thunderbird, the last Athlon processor using the Thunderbird core was released in 2001 in the summer, at which point speeds were at 1.4 GHz. Specifications - L1-cache: 64 + 64 KB (data + instructions) - L2-cache: 256 KB, full speed - MMX, 3DNow! - Slot A & Socket A (EV6) - Front-side bus: 100 MHz (Slot-A, B-models), 133 MHz (C-models) (200 MT/s, 266 MT/s) - Vcore: 1.70--1.75 V - First release: June 4, 2000 - Transistor count: 37 million - Manufacturing process: /180 nm - Clock rate: - Slot A: 650--1000 MHz - Socket A, 100 MHz FSB (B-models): 600--1400 MHz - Socket A, 133 MHz FSB (C-models): 1000--1400 MHz ### Athlon XP (2001--2003) {#athlon_xp_20012003} Overall, there are four main variants of the Athlon XP desktop CPU: the Palomino, the Thoroughbred, the Thorton, and the Barton. A number of mobile processors were also released, including the Corvette models, and the Dublin model among others. #### Palomino On May 14, 2001, AMD released the Athlon XP processor. It debuted as the Mobile Athlon 4, a mobile version codenamed Corvette, with the desktop Athlon XP released in the fall. The third-generation Athlon, code-named Palomino, came out on October 9, 2001, as the Athlon XP, with the suffix signifying extreme performance and unofficially referencing Windows XP. Palomino\'s design used 180 nm fabrication process size. The Athlon XP was marketed using a performance rating (PR) system comparing it to the Thunderbird predecessor core. Among other changes, Palomino consumed 20% less power than the Thunderbird, comparatively reducing heat output, and was roughly 10% faster than Thunderbird. Palomino also had enhanced K7\'s TLB architecture and included a hardware data prefetch mechanism to take better advantage of memory bandwidth. Palomino was the first K7 core to include the full SSE instruction set from the Intel Pentium III, as well as AMD\'s 3DNow! Professional. Palomino was also the first socketed Athlon officially supporting dual processing, with chips certified for that purpose branded as the Athlon MP (multi processing), which had different specifications. According to HardwareZone, it was possible to modify the Athlon XP to function as an MP. Specifications - L1-cache: 64 + 64 KB (data + instructions) - L2-cache: 256 KB, full speed - MMX, 3DNow!, SSE - Socket A (EV6) - Front-side bus: 133 MHz (266 MT/s) - Vcore: 1.50 to 1.75 V - Power consumption: 68 W - First release: October 9, 2001 - Clock-rate: - Athlon 4: 850--1400 MHz - Athlon XP: 1333--1733 MHz (1500+ to 2100+) - Athlon MP: 1000--1733 MHz #### Thoroughbred The fourth-generation of Athlon was introduced with the Thoroughbred core, or T-Bred, on April 17, 2002. The Thoroughbred core marked AMD\'s first production 130 nm silicon, with smaller die size than its predecessor. There came to be two steppings (revisions) of this core commonly referred to as Tbred-A and Tbred-B. Introduced in June 2002, the initial A version was mostly a direct die shrink of the preceding Palomino core, but did not significantly increase clock speeds over the Palomino. A revised Thoroughbred core, Thoroughbred-B, added a ninth \"metal layer\" to the eight-layered Thoroughbred-A, offering improvement in headroom over the A and making it popular for overclocking. Specifications - L1-cache: 64 + 64 KB (data + instructions) - L2-cache: 256 KB, full speed - MMX, 3DNow!, SSE - Socket A (EV6) - Front-side bus: 133/166 MHz (266/333 MT/s) - Vcore: 1.50--1.65 V - First release: June 10, 2002 (A), August 21, 2002 (B) - Clock-rate: - Thoroughbred \"A\": 1400--1800 MHz (1600+ to 2200+) - Thoroughbred \"B\": 1400--2250 MHz (1600+ to 2800+) - 133 MHz FSB: 1400--2133 MHz (1600+ to 2600+) - 166 MHz FSB: 2083--2250 MHz (2600+ to 2800+) #### Barton / Thorton {#barton_thorton} Fifth-generation Athlon Barton-core processors were released in early 2003. While not operating at higher clock rates than Thoroughbred-core processors, they featured an increased L2 cache, and later models had an increased 200 MHz (400 MT/s) front side bus. The Thorton core, a blend of Thoroughbred and Barton, was a later variant of the Barton with half of the L2 cache disabled. The Barton was used to officially introduce a higher 400 MT/s bus clock for the Socket A platform, which was used to gain some Barton models more efficiency. By this point with the Barton, the four-year-old Athlon EV6 bus architecture had scaled to its limit and required a redesign to exceed the performance of newer Intel processors. By 2003, the Pentium 4 had become more than competitive with AMD\'s processors, and Barton only saw a small performance increase over the Thoroughbred-B it derived from, insufficient to outperform the Pentium 4. The K7-derived Athlons such as Barton were replaced in September 2003 by the Athlon 64 family, which featured an on-chip memory controller and a new HyperTransport bus. Notably, the 2500+ Barton with 11× multiplier was effectively identical to the 3200+ part other than the FSB speed it was binned for, meaning that seamless overclocking was possible more often than not. Early Thortons could be restored to the full Barton specification with the enabling of the other half of the L2 cache from a slight CPU surface modification, but the result was not always reliable. Specifications: Barton (130 nm) - L1-cache: 64 + 64 KB (data + instructions) - L2-cache: 512 KB, full speed - MMX, 3DNow!, SSE - Socket A (EV6) - Front-side bus: 166/200 MHz (333/400 MT/s) - Vcore: 1.65 V - First release: February 10, 2003 - Clock rate: 1833--2333 MHz (2500+ to 3200+) - 133 MHz FSB: 1867--2133 MHz (2500+ to 2800+); uncommon - 166 MHz FSB: 1833--2333 MHz (2500+ to 3200+) - 200 MHz FSB: 2100, 2200 MHz (3000+, 3200+) Thorton (130 nm) - L1-cache: 64 + 64 KB (Data + Instructions) - L2-cache: 256 KB, full speed - MMX, 3DNow!, SSE - Socket A (EV6) - Front-side bus: 133/166/200 MHz (266/333/400 MT/s) - Vcore: 1.50--1.65 V - First release: September 2003 - Clock rate: 1667--2200 MHz (2000+ to 3100+) - 133 MHz FSB: 1600--2133 MHz (2000+ to 2600+) - 166 MHz FSB: 2083 MHz (2600+) - 200 MHz FSB: 2200 MHz (3100+) #### Mobile Athlon XP {#mobile_athlon_xp} The Palomino core debuted in the mobile market before the PC market in May 2001, where it was branded as Mobile Athlon 4 with the codename \"Corvette\". It distinctively used a ceramic interposer much like the Thunderbird instead of the organic pin grid array package used on all later Palomino processors. In November 2001, AMD released a 1.2 GHz Athlon 4 and a 950 MHz Duron. The Mobile Athlon 4 processors included the PowerNow! function, which controlled a laptop\'s \"level of processor performance by dynamically adjusting its operating frequency and voltage according to the task at hand\", thus extending \"battery life by reducing processor power when it isn\'t needed by applications\". Duron chips also included PowerNow! In 2002, AMD released a version of PowerNow! called Cool\'n\'Quiet, implemented on the Athlon XP but only adjusting clock speed instead of voltage. In 2002 the Athlon XP-M (Mobile Athlon XP) replaced the Mobile Athlon 4 using the newer Thoroughbred core, with Barton cores for full-size notebooks. The Athlon XP-M was also offered in a compact microPGA socket 563 version. Mobile XPs were not multiplier-locked, making them popular with desktop overclockers. ### Athlon 64 (2003--2009) {#athlon_64_20032009} The immediate successor to the Athlon XP, the Athlon 64 is an AMD64-architecture microprocessor produced by AMD, released on September 23, 2003. A number of variations, all named after cities, were released with 90 nm architecture in 2004 and 2005. Versions released in 2007 and 2009 utilized 65 nm architecture. ### Athlon 64 X2 (2005--2009) {#athlon_64_x2_20052009} The Athlon 64 X2 was released in 2005 as the first native dual-core desktop CPU designed by AMD using an Athlon 64. The Athlon X2 was a subsequent family of microprocessors based on the Athlon 64 X2. The original Brisbane Athlon X2 models used 65 nm architecture and were released in 2007. ### Athlon II (2009--2012) {#athlon_ii_20092012} Athlon II is a family of central processing units. Initially a dual-core version of the Athlon II, the K-10-based Regor was released in June 2009 with 45-nanometer architecture. This was followed by a single-core version Sargas, followed by the quad-core Propus, the triple-core Rana in November 2009, and the Llano 32 nm version released in 2011. ### Piledriver and Steamroller-based Athlon X4 (2013--2016) {#piledriver_and_steamroller_based_athlon_x4_20132016} Various Steamroller-based Athlon X4 and X2 FM2+ socketed processors were released in 2014 and the years after. The preceding Piledriver-based Athlon X4 and X2 processors were released before 2014, and are socket compatible with both FM2+ and FM2 mainboards. ### Excavator-based Athlon X4 (2017) {#excavator_based_athlon_x4_2017} The Bristol Ridge Athlon X4 lineup was released in 2017. It is based on the Excavator microarchitecture and uses 2 Excavator modules totalling 4 cores. It has a dual-channel DDR4-2400 memory controller with clock speeds up to 4.0 GHz. It runs on the new Socket AM4 platform that was later used for Zen 1 to Zen 3 CPUs. ### Zen-based Athlon (2018--present) {#zen_based_athlon_2018present} The Zen-based Athlon with Radeon graphics processors was launched in September 2018 with the Athlon 200GE. Based on AMD\'s Raven Ridge core previously used in variants of the Ryzen 3 and Ryzen 5, the Athlon 200GE had half of the cores but left SMT enabled. It also kept the same 4 MiB L3 cache, but the L2 cache was halved to 1 MiB. In addition, the number of graphics compute units was limited to 3 in the Athlon 200GE, and the chip was multiplier-locked. Despite its limitations, the Athlon 200GE performed competitively against the 5000-series Intel Pentium-G, displaying similar CPU performance but an advantage in GPU performance. On November 19, 2019, AMD released the Athlon 3000G, with a higher 3.5 GHz core clock and 1100 MHz graphics clock compared to the Athlon 200GE, also with two cores. The main functional difference between the 200GE was the Athlon 3000G\'s unlocked multiplier, allowing the latter to be overclocked on B450 and X470 motherboards. Zen 2-based Athlon with Radeon Graphics processors, codenamed \"Mendocino\", were released on September 20, 2022, for the entry-level laptop market, alongside the more powerful quad-core Ryzen 7020 mobile series under the same codename. Featuring two processing cores, with two threads on Athlon Silver and four threads on Athlon Gold models, Athlon 7020 series mobile processors are equipped with two compute units (CUs) of RDNA 2 graphics. These 7020U series models were followed by the release of Ryzen/Athlon 7020C series for Chromebooks on May 23, 2023. Unlike prior Athlon generations, AMD has not released desktop variants of Mendocino. Specifications Raven Ridge (14 nm), Picasso (12 nm) (see the list article for more details) - L1 cache: 192 KiB (2×64 KiB + 2×32 KiB) - L2 cache: 1 MiB (2×512 KiB) - L3 cache: 4 MiB - Memory: dual-channel DDR4-2666, 64 GiB max. - Socket AM4 - TDP: 35 W - First release: September 6, 2018 - CPU clock rate: 3.2 to 3.5 GHz - GPU clock rate: 1000 to 1100 MHz Mendocino (6 nm) (see the list article for more details) - L1 cache: 128 KiB (2×32 KiB + 2×32 KiB) - L2 cache: 1 MiB (2×512 KiB) - L3 cache: 4 MiB - Memory: dual-channel LPDDR5-5500, 16 GiB max. - TDP: 15 W - First release: September 20, 2022 - CPU clock rate: 2.4 GHz - GPU clock rate: 1900 MHz ## Supercomputers A number of supercomputers have been built using Athlon chips, largely at universities. Among them: - In 2000, several American students claimed to have built the world\'s least expensive supercomputer by clustering 64 AMD Athlon chips together, also marking the first time Athlons had been clustered in a supercomputer. - The PRESTO III, a Beowulf cluster of 78 AMD Athlon processors, was built in 2001 by the Tokyo Institute of Technology. That year it ranked 439 on the TOP500 list of supercomputers. - In 2002, a \"128-Node 256-Processor AMD Athlon Supercomputer Cluster\" was installed at the Ohio Supercomputer Center at the University of Toledo. - Rutgers University, Department of Physics & Astronomy. Machine: NOW Cluster---AMD Athlon. CPU: 512 AthlonMP (1.65 GHz). Rmax: 794 GFLOPS.	2025-06-20T00:00:00
3,074	Androphagi	The Androphagi were an ancient Scythian tribe whose existence was recorded by ancient Greco-Roman authors. The Androphagi were closely related to the Melanchlaeni and the Budini. ## Name The name `{{Transliteration\|la\|Androphagi}}`{=mediawiki} is a Latinisation of the ancient Greek name `{{Transliteration\|grc\|Androphagoi}}`{=mediawiki} (Ἀνδροφάγοι), which meant \"Man-Eaters.\" This name is a descriptive one based on this tribe\'s practice of cannibalism, and their own tribal name is unknown. ## Location The Androphagi lived in the region to the east of the middle Dnipro river, especially in the valley of the Sula and some smaller rivers. The neighbours of the Androphagi were the Neuri to the west and the Scythians to the south. ## History ### Origin The Scythians originated in the region of the Volga-Ural steppes of Central Asia, possibly around the 9th century BC, as a section of the population of the Srubnaya culture containing a significant element originating from the Siberian Andronovo culture. The population of the Srubnaya culture was among the first truly nomadic pastoralist groups, who themselves emerged in the Central Asian and Siberian steppes during the 9th century BC as a result of the cold and dry climate then prevailing in these regions. During the 9th to 8th centuries BC, a significant movement of the nomadic peoples of the Eurasian Steppe started when another nomadic Iranic tribe closely related to the Scythians from eastern Central Asia, either the Massagetae or the Issedones, migrated westwards, forcing the early Scythians to the west across the Araxes river. Over the course of the 8th and 7th centuries BC, the Scythians migrated into the Caucasian and Caspian Steppes in several waves, becoming the dominant population of the region, where they assimilated most of the Cimmerians and conquered their territory, with this absorption of the Cimmerians by the Scythians being facilitated by their similar ethnic backgrounds and lifestyles, after which the Scythians settled in the area between the Araxes, the Caucasus and the Lake Maeotis. The section of the Scythians from whom the Androphagi originated participated in this migration, and had established itself in Ciscaucasia around `{{c.\|800 BC}}`{=mediawiki}. From their base in the Caucasian Steppe, during the period of the 8th to 7th centuries BC itself, the Scythians conquered the Pontic and Crimean Steppes to the north of the Black Sea up to the Danube river, which formed the western boundary of Scythian territory onwards, with this process of Scythian takeover of the Pontic Steppe becoming fully complete by the 7th century BC. Archaeologically, the westwards migration of the Early Scythians from Central Asia into the Caspian Steppe constituted the latest of the two to three waves of expansion of the Srubnaya culture to the west of the Volga. The last and third wave corresponding to the Scythian migration has been dated to the 9th century BC. The expansion of the Scythians into the Pontic Steppe is attested through the westward movement of the Srubnaya-Khvalynsk culture into Ukraine. The Srubnaya-Khvalynsk culture in Ukraine is referred to in scholarship as the \"Late Srubnaya\" culture. ### Migration towards the forest steppe {#migration_towards_the_forest_steppe} From the Caucasian steppe, the tribe of the Royal Scythians expanded to the south, following the coast of the Caspian Sea and arrived in the Ciscaucasian steppes, from where they settled in eastern Transcaucasia until the early 6th century BC. The Royal Scythians were finally expelled from West Asia in the `{{c.\|600s BC}}`{=mediawiki}, after which, beginning in the later 7th and lasting throughout much of the 6th century BC, the majority of the Scythians migrated from Ciscaucasia into the Pontic Steppe, which became the centre of Scythian power. The retreat of the Royal Scythians from West Asia into the Pontic steppe pushed a Scythian splinter group to the north, into the region of Donets-Kramatorsk, where they formed the Vorskla and Sula-Donets groups of the Scythian culture, of which the Donets group corresponded to the Melanchlaeni, the Sula group to the Androphagi, and the Vorskla group to the Budini, with all of these groups remaining independent from the Scythians proper. This splinter group arrived in the forest-steppe region in part from the Kuban region, but for the most from northern Ciscaucasia. Of these groups, the Androphagi and the Melanchlaeni were closely related tribes. ### The Persian invasion {#the_persian_invasion} When the Persian Achaemenid king Darius I attacked the Scythians in 513 BC, the Scythian king Idanthyrsus summoned the kings of the peoples surrounding his kingdom to a meeting to decide how to deal with the Persian invasion. The kings of the Budini, Gelonians, and Sarmatians accepted to help the Scythians against the Persian attack, while the kings of the Agathyrsi, Androphagi, Melanchlaeni, Neuri, and Tauri refused to support the Scythians. During the campaign, the Scythians and the Persian army pursuing them passed through the territories of the Melanchlaeni, Androphagi, and Neuri, before they reached the borders of the Agathyrsi, who refused to let the Scythian divisions to pass into their territories and find refuge there, thus forcing the Scythians to return to Scythia with the Persians pursuing them. ## Society and culture {#society_and_culture} The ancient Greek author Herodotus of Halicarnassus described the Androphagi as wearing Scythian-type clothing, and speaking a \"peculiar language.\" ### Lifestyle The Androphagi were largely engaged in agriculture and farming, and hunting was of lesser importance among them. ### Language The \"peculiar language\" of the Androphagi might have been a dialect of Iranic language different from that of the Pontic Scythians. The Sula group of the Scythian culture which corresponded to the Androphagi was part of an area of Iranic toponymy and hydronymy. ### Ritual cannibalism {#ritual_cannibalism} Herodotus of Halicarnassus claimed that the Androphagi were the only ones who practised cannibalism among the peoples living near Scythia, which seems to be confirmed by the intact and unbroken human bones of seventeen individuals which were found along with cut and broken animal bones in the kitchen refuse of seven Androphagi earthworks. However, traces of similar ritual cannibalism are recorded from seven earthworks of the Melanchlaeni and Budini, as well as in the Smiela kurgan 15, which was one of the earliest burials of the Tiasmyn group of the Scythian culture. The Sauromatians who lived in the Urals and the lower Volga, and Massagetae and Issedones to the east of the Urals, practised similar ritual cannibalism, suggesting that the early Scythic peoples of the Central Asian steppe had customs and beliefs connected to ritual cannibalism. ### Trade Trade relations between the Androphagi and the ancient Greek colonies on the northern shores of the Black Sea had been established in the 6th century BC. ## Archaeology The Androphagi archaeologically belonged to the Scythian culture, and they corresponded to its Sula group, which was the largest Scythian culture group of the eastern European forest steppe zone. The Donets, Sula and Vorskla groups of the Scythian culture, respectively corresponding to the Melanchlaeni, Androphagi, and Budini, are sometimes grouped the Zolnichnaya (that is \"Ash-Mounds\") culture because of the presence of several `{{Transliteration\|uk\|zolnyk}}`{=mediawiki} (зольник), that is ash mounds containing refuse from kitchens and other sources, near dwellings. The three groups of the Zolnichnaya culture were closely related to each other, with the Vorskla group nevertheless exhibiting enough significant differences from the Sula and Donets groups that the latter two are sometimes grouped together as a Sula-Donets group distinct from the Vorskla group. The earliest Scythians had belonged to the Srubnaya culture culture, and, like the Donets group of the Scythian culture which corresponds to the Melanchlaeni, the Sula group of the Scythian culture contained an important element of the Srubnaya culture in its substratum, although there were some differences between the Donets and Sula groups.	2025-06-20T00:00:00
3,082	Alexandria, Indiana	Alexandria is a city in Monroe Township, Madison County, Indiana, United States. It is about 48 mi northeast of Indianapolis. According to the 2020 census, its population was 5,149, nearly unchanged from 2010. ## History Alexandria was platted in 1836, when it was certain that the Indiana Central Canal would be extended to that point. It was incorporated as a town in 1898. In 1898, Indiana\'s first Interurban railway line began operating between Alexandria and Anderson. ## Geography Alexandria is located in northern Madison County. Indiana State Road 9 passes through the east side of the city, leading south 11 mi to Anderson, the county seat, and north 21 mi to Marion. State Road 28 crosses the northern tip of Alexandria, leading west 9 mi to Elwood and east 23 mi to Albany. According to the U.S. Census Bureau, Alexandria has a total area of 3.0 sqmi, all land. Pipe Creek crosses the city south of its center, flowing southwest to join the White River at Perkinsville. ## Demographics Alexandria is part of the Indianapolis--Carmel--Anderson metropolitan statistical area. ### 2010 census As of the census of 2010, there were 5,145 people, 2,113 households, and 1,362 families living in the city. The population density was 1956.3 PD/sqmi. There were 2,507 housing units at an average density of 953.2 /sqmi. The racial makeup of the city was 97.4% White, 0.3% African American, 0.1% Native American, 0.2% Asian, 0.8% from other races, and 1.1% from two or more races. Hispanic or Latino people of any race were 1.7% of the population. Of the 2,113 households 33.6% had children under the age of 18 living with them, 42.2% were married couples living together, 15.7% had a female householder with no husband present, 6.6% had a male householder with no wife present, and 35.5% were non-families. 30.1% of households were one person and 12.8% were one person aged 65 or older. The average household size was 2.41 and the average family size was 2.95. The median age was 38.2 years. 25.6% of residents were under the age of 18; 8.8% were between the ages of 18 and 24; 24.8% were from 25 to 44; 25.1% were from 45 to 64; and 15.6% were 65 or older. The gender makeup of the city was 47.8% male and 52.2% female. ### 2000 census {#census_1} As of the census of 2000, there were 6,260 people, 2,481 households, and 1,654 families living in the city. The population density was 2,308.6 PD/sqmi. There were 2,704 housing units at an average density of 997.2 /sqmi. The racial makeup of the city was 98.10% White, 0.46% Black or African American, 0.08% Native American, 0.11% Asian, 0.02% Pacific Islander, 0.43% from other races, and 0.80% from two or more races. 0.99% of the population were Hispanic or Latino of any race. Of the 2,481 households 33.9% had children under the age of 18 living with them, 49.0% were married couples living together, 12.7% had a female householder with no husband present, and 33.3% were non-families. 28.9% of households were one person and 13.1% were one person aged 65 or older. The average household size was 2.48 and the average family size was 3.04. The age distribution was 27.8% under the age of 18, 8.9% from 18 to 24, 28.0% from 25 to 44, 19.5% from 45 to 64, and 15.9% 65 or older. The median age was 35 years. For every 100 females, there were 91.4 males. For every 100 females age 18 and over, there were 87.4 males. The median household income was \$35,359 and the median family income was \$42,731. Males had a median income of \$30,529 versus \$23,384 for females. The per capita income for the city was \$15,578. About 4.2% of families and 7.0% of the population were below the poverty line, including 4.1% of those under age 18 and 15.0% of those age 65 or over. ## Government The city council consists of seven members. Five members are elected from individual districts, and two are elected at large. The city is governed by a \"strong\" mayor system that appoints two council members and/or city residents to serve at the mayor\'s pleasure on the board of public works and safety. The chief financial officer is the clerk-treasurer. The clerk-treasurer and mayor are full-time elected officials. ## Transportation ### Airport Alexandria Airport is a public use airport located 3 mi southeast of the central business district of Alexandria. ## Education It is in the Alexandria Community School Corporation. The town has a lending library, the Alexandria-Monroe Public Library. ## Notable people {#notable_people} - Joey Feek, country singer - Bill Gaither, gospel singer/songwriter - Danny Gaither, gospel singer - Gloria Gaither, author/lyricist, gospel singer - Robert L. Rock, politician ## Gallery <File:Clock> in Alexandria, Indiana.jpg\\|Clock in Alexandria, Indiana <File:Fountain> in park in Alexandria.jpg\\|Fountain in park in Alexandria <File:The> Commons Theatre in Alexandria Indiana.jpg\\|The Commons Theatre in Alexandria Indiana <File:Harrison> Street, Alexandria, Indiana (74009).jpg\\|Harrison Street in Alexandria, circa 1930--1945 <File:Beulah> Park Swimming Pool, Alexandria, Indiana (74010).jpg\\|Beulah Park Swimming Pool in Alexandria, circa 1930--1945 <File:Welcome> to Alexandria.jpg\\|Welcome to Alexandria	2025-06-20T00:00:00
3,085	Alexandria Troas	Alexandria Troas (\"Alexandria of the Troad\"; Αλεξάνδρεια Τρωάς; Eski Stambul, \"Old Istanbul\") is the site of an ancient Greek city situated on the Aegean Sea near the northern tip of Turkey\'s western coast, the area known historically as Troad, a little south of Tenedos (modern Bozcaada). It is located southeast of modern Dalyan, a village in the Ezine district of Çanakkale Province. The site sprawls over an estimated 400 ha; among the few structures remaining today are a ruined bath, an odeon, a theatre, gymnasium complex and a recently uncovered stadion. The circuit of the old walls can still be traced. ## History ### Hellenistic According to Strabo, this site was first called Sigia (Σιγία); around 306 BC Antigonus refounded the city as the much-expanded Antigonia Troas by settling the people of five other towns in Sigia, including the once influential city of Neandreia. It did not receive its name until its name was changed by Lysimachus to Alexandria Troas, in 301 BC, in memory of Alexander the Great of Macedon (Pliny merely states that the name changed from Antigonia to Alexandria). The city continued being called Alexandria Troas, as is stated in the 4th-5th c. AD Tabula Peutingeriana. As the chief port of north-west Asia Minor, the place prospered greatly in Roman times, becoming a \"free and autonomous city\" as early as 188 BC, and the existing remains sufficiently attest its former importance. In its heyday the city may have had a population of about 100,000. Strabo mentions that a Roman colony was created at the location in the reign of Augustus, named Colonia Alexandria Augusta Troas (called simply Troas during this period). Augustus, Hadrian and the rich grammarian Herodes Atticus contributed greatly to its embellishment; the aqueduct still preserved is due to the latter. Julius Caesar and Constantine considered making Troas the capital of the Roman Empire. ### Roman In Roman times, it was a significant port for travelling between Anatolia and Europe. According to the account in the Acts of the Apostles, Paul of Tarsus sailed for Europe for the first time from Alexandria Troas and returned there from Europe (it was there that the episode of the raising of Eutychus occurred). Ignatius of Antioch also paused at this city before continuing to his martyrdom at Rome. ### Byzantine Several of its later bishops are known: Marinus in 325; Niconius in 344; Sylvanus at the beginning of the 5th century; Pionius in 451; Leo in 787; Peter, friend of the Patriarch Ignatius, and adversary to Michael, in the ninth century. In the 10th century Troas is given as a suffragan of Cyzicus and distinct from the famous Troy (Heinrich Gelzer, Ungedruckte \... Texte der Notitiae episcopatuum, 552; Georgii Cyprii descriptio orbis romani, 64); it is not known when the city was destroyed and the diocese disappeared. The bishopric remains a titular see of the Catholic Church under the name Troas, vacant since 1971. Troas is also a titular see of the Eastern Orthodox Church under the Ecumenical Patriarchate. Bishop Savas (Zembillas) of Troas served as hierarch from 2002 to 2011, and then became Metropolitan Savas (Zembillas) of Pittsburgh in the Greek Orthodox Archdiocese of America. ### Ottoman Karasid Turkomans settled in the area of the Troad in the 14th century. Their beylik was conquered by the Ottomans in 1336. The ruins of Alexandria Troas came to be known among the Turks as Eski Stambul, the \"Old City\". The site\'s stones were much plundered for building material (for example Mehmed IV took columns to adorn his Yeni Valide Mosque in Istanbul). As of the mid-18th century the site served as \"a lurking place for bandetti\". ### Modern By 1911, the site had been overgrown with Vallonea oaks and much plundered, but the circuit of the old walls could still be traced, and in several places they were fairly well preserved. They had a circumference of about ten kilometres, and were fortified with towers at regular intervals. Remains of an ancient bath and gymnasium complex can be found within this area; this building is locally known as Bal Saray (Honey Palace) and was originally endowed by Herodes Atticus in the year 135. Trajan built an aqueduct which can still be traced. The harbour had two large basins, now almost choked with sand. It is the subject of an early twenty-first century study by German archaeologists digging and surveying at the site. Their excavation uncovered the remains of a large stadium dating to about 100 BC.	2025-06-20T00:00:00
3,087	Alexandria, West Dunbartonshire	Alexandria (The Vale, Alexandria) is a town in West Dunbartonshire, Scotland. The town is on the River Leven, 3 mi north of Dumbarton and 15 mi north-west of Glasgow. ## Demographics In 2016, the estimated population of the town was 6,860. It is one of five towns in the Vale of Leven, the others being Balloch, Bonhill, Jamestown and Renton; their combined population is over 20,000. ## Economy The town\'s traditional industries, most importantly cotton manufacturing, bleaching and printing, have been phased out. In the 1970s Alexandria was redeveloped, with a new town centre layout and traffic system. Local landmarks include Christie Park and the Category B listed Smollett Fountain in the town centre. Lomond Galleries on North Main Street is a former car factory with an impressive dome and an even more impressive marble entrance hall and staircase. It was originally built in 1906 as the Argyll Motor Works, for Argyll Motors Ltd. A carving above the entrance shows one of the company\'s cars. After the car production ceased in 1914, it was used by the Admiralty for the manufacture of torpedoes, which were test-fired in Loch Long, and in the early 1970s was the scene of the Plessey sit-in. The building now hosts a shopping mall but has retained many of its striking architectural features. Major employers in the area were Westclox and Polaroid, both based in the Leven Industrial Estate; Aggreko based a major purpose-built factory in the estate from 2000 to 2010. The Ballantine\'s whisky distillery continues to operate in the estate. ## Transport Alexandria sits on the former A82 main road between Glasgow and Loch Lomond. There are regular bus services on the route, and the town has a railway station on the rail line between Balloch and Glasgow Queen Street. Alexandria is reputed to be the only town in the UK with a railway station, carnival (periodically Codona\'s travelling fair sets up in the car park) and a pub in the middle of a roundabout. A. J. Cronin\'s uncle owned a pub in Bridge Street. Alexandria Library is located on Gilmour Street. ## Sport The town is home to Vale of Leven football club, who play at Millburn Park. The club was a dominant force in early Scottish football history, winning the Scottish Cup in 1877, 1878 and 1879, and were founder members of the Scottish Football League. Gordon Reid, born in Alexandria, has won the Wimbledon Tennis Men\'s Wheelchair Doubles, with his partner Alfie Hewett, three times. ## ROC Bunker {#roc_bunker} Between 1961 and 1991, the village was the location of a Royal Observer Corps Master bunker, to be used in the event of a nuclear attack. It remains mostly intact. ## Notable natives and residents {#notable_natives_and_residents} - Stuart David, writer and musician (Belle and Sebastian) - Zander Diamond, Scottish professional footballer - John Miller \"Ian\" McColl, Scottish footballer and manager of the Scotland national team - Morgan McMichaels, Scottish-American drag queen and reality television personality - Dawn O\'Porter, British writer, director and television presenter - Bobby Kerr, Scottish professional footballer, captain of Sunderland A.F.C.\'s 1973 FA Cup-winning team ```{=html} <!-- --> ``` - Malcolm Finlayson (14 June 1930 -- 26 November 2014) was a Scottish football goalkeeper who won the Football League Championship and FA Cup with Wolverhampton Wanderers.	2025-06-20T00:00:00
3,088	Alexandria, Romania	Alexandria (`{{IPA\|ro\|alekˈsandri.a\|-\|Ro-Alexandria.ogg}}`{=mediawiki}) is the capital city of the Teleorman County, Muntenia, Romania. It is located south-west of Bucharest, towards the Bulgarian border, and has over 40,000 inhabitants. The 44th parallel north passes just north of the city. ## Geography Alexandria is situated in the middle of the Wallachian Plain, on the banks of the Vedea River. It is located in the central part of Teleorman County, at a distance of 62 km from Giurgiu and 86 km from Bucharest. The city is traversed by the national road DN6, which links Bucharest to the Banat region in western Romania; the road is part of European route E70. The Alexandria train station serves the CFR Line 909, with service towards Roșiorii de Vede (to the northwest) and Zimnicea (to the south, on the Danube). `{{Weather box \|width = auto \|metric first = yes \|single line = yes \|location = Alexandria, Romania \|precipitation colour = green \| Jan high C =2.3 \| Feb high C =5.3 \| Mar high C =12.1 \| Apr high C =18.3 \| May high C =23.0 \| Jun high C =27.5 \| Jul high C =29.8 \| Aug high C =31.1 \| Sep high C =25.7 \| Oct high C =17.6 \| Nov high C =11.9 \| Dec high C =4.8 \| Jan low C =-3.3 \| Feb low C =-0.8 \| Mar low C =4.0 \| Apr low C =7.6 \| May low C =11.9 \| Jun low C =15.9 \| Jul low C =17.8 \| Aug low C =18.8 \| Sep low C =15.2 \| Oct low C =9.9 \| Nov low C =5.6 \| Dec low C =-0.5 \| Jan precipitation mm =55.7 \| Feb precipitation mm =38.6 \| Mar precipitation mm =54.1 \| Apr precipitation mm =57.3 \| May precipitation mm =71.6 \| Jun precipitation mm =106.5 \| Jul precipitation mm =70.9 \| Aug precipitation mm =40.2 \| Sep precipitation mm =34.9 \| Oct precipitation mm =58.7 \| Nov precipitation mm =39.8 \| Dec precipitation mm =47.4 \| Jan snow cm = 6.5 \| Feb snow cm = 6.8 \| Mar snow cm = 2.9 \| Apr snow cm = 0 \| May snow cm = 0 \| Jun snow cm = 0 \| Jul snow cm = 0 \| Aug snow cm = 0 \| Sep snow cm = 0 \| Oct snow cm = 0 \| Nov snow cm = 0.8 \| Dec snow cm = 4.7 \| unit precipitation days = 0.1 mm \| Jan precipitation days =10.1 \| Feb precipitation days =9.3 \| Mar precipitation days =11.8 \| Apr precipitation days =9.9 \| May precipitation days =12.2 \| Jun precipitation days =11.8 \| Jul precipitation days =7.6 \| Aug precipitation days =5.5 \| Sep precipitation days =6.1 \| Oct precipitation days =8 \| Nov precipitation days =11.3 \| Dec precipitation days =9.2 \| year precipitation days = \| Jan snow days =6.7 \| Feb snow days =4.1 \| Mar snow days =3.1 \| Apr snow days =0 \| May snow days =0 \| Jun snow days =0 \| Jul snow days =0 \| Aug snow days =0 \| Sep snow days =0 \| Oct snow days =0.8 \| Nov snow days =1.5 \| Dec snow days =3.7 \| Jan humidity =85 \| Feb humidity =82 \| Mar humidity =70 \| Apr humidity =64 \| May humidity =67 \| Jun humidity =64 \| Jul humidity =58 \| Aug humidity =49 \| Sep humidity =52 \| Oct humidity =65 \| Nov humidity =74 \| Dec humidity =80 \| Jan light = 9.3 \| Feb light = 10.5 \| Mar light = 12 \| Apr light = 13.5 \| May light = 14.8 \| Jun light = 15.4 \| Jul light = 15.1 \| Aug light = 14 \| Sep light = 12.5 \| Oct light = 11 \| Nov light = 9.7 \| Dec light = 9 \| Jan uv =1 \| Feb uv =2 \| Mar uv =4 \| Apr uv =4 \| May uv =5 \| Jun uv =6 \| Jul uv =6 \| Aug uv =6 \| Sep uv =5 \| Oct uv =3 \| Nov uv =2 \| Dec uv =2 \|source = Weather Atlas<ref>{{Cite web \|url=https://www.weather-atlas.com/en/romania/alexandria-climate \|title=Yearly & Monthly Weather - Alexandria, Romania \|access-date=2023-09-12 \|website=Weather Atlas}}</ref> World Weather Online(precipitation-UV 2009-2023),<ref>{{Cite web \|url=https://www.worldweatheronline.com/alexandria-weather-averages/teleorman/ro.aspx \|title=Alexandria Annual Weather Averages \|access-date=2023-09-12 \|website=World Weather Online}}</ref> Meteomanz(precipitation days, snow days 2014-2023<ref>{{Cite web \|url=http://www.meteomanz.com/sy3?l=1&cou=6240&ind=15489&m1=01&y1=2000&m2=07&y2=2024 \|title=Alexandria - Weather data by months \|access-date=7 July 2024 \|website=Meteomanz}}</ref>) }}`{=mediawiki} ## History Alexandria was named after its founder, Alexandru D. Ghica, Prince of Wallachia from April 1834 to 7 October 1842. Its population in 1900 was 1,675. Grain, which was Alexandria\'s main trade at the time, was dispatched both by rail to the Danubian port of Zimnicea and by river to Giurgiu. In 1989, the city had over 63,000 inhabitants and more than six large factories. The 2021 census puts the population at 40,390. ## Education There are four high schools in Alexandria: the Alexandru D. Ghica National College, the Alexandru Ioan Cuza Theoretical High School, the Mircea Scarlat National Pedagogical College and the Constantin Noica Theoretical High School. In 1897, the Ștefan cel Mare School moved from its former location to 310 Libertății Street; a local entrepreneur, M. Frangulea, obtained the plot and hired renowned architect Alexandru Săvulescu to build the new boys\' primary school for the city. ## Religion The Diocese of Alexandria and Teleorman is a diocese of the Romanian Orthodox Church. Its see is Saint Alexander Cathedral in Alexandria and its ecclesiastical territory covers Teleorman County. ## Sports CSM Alexandria is a football club founded in 1948; it plays in the Romanian Liga III. CS Universitatea Alexandria is a women\'s football club founded in 2012. Stadionul Municipal, which holds 5,000 people, is the home ground for both clubs; the stadium is currently undergoing reconstruction. The Alexandria women\'s basketball team plays in the Liga Națională. ## Natives - Valentin Badea (b. 1982), footballer - Dan Balauru (b. 1980), footballer - Adrian Bădulescu (b. 1967), politician - (b. 1966), fashion creator - (1899--1976), mayor, lawyer, writer - Anghel Demetriescu (1847--1903), historian - Gheorghe Mihăilescu (1888--?), World War I pilot - Ciprian Manolescu (b. 1978), mathematician - Andreea Ogrăzeanu (b. 1990), sprinter - Florin Olteanu (b. 1981), footballer - Sorin Paraschiv (b. 1981), footballer - Alin Pencea (b. 1992), footballer - Marin Stan (b. 1950), sports shooter - Alina Tecșor (b. 1979), tennis player - Alin Toșca (b. 1992), footballer - Daniel Tudor (b. 1974), footballer - Mihai Verbițchi (b. 1957), actor - Ionuț Voicu (b. 1984), footballer ## Gallery	2025-06-20T00:00:00
3,089	Angela Vincent	Angela Vincent (born 1942) is a British neuroscientist who is emeritus professor at the University of Oxford and a Fellow of Somerville College, Oxford. ## Career and research {#career_and_research} Angela Vincent was born in 1942, the third child of Carmen and Joseph Molony (later KCVO). After St Mary\'s Convent, Ascot, she studied medicine at King\'s College London and Westminster Hospital School of Medicine (now merged with Imperial College School of Medicine). After one year as a junior doctor at St Steven\'s and St Charles\' hospitals in London (1966--1967), she obtained an MSc in biochemistry from University College London. In 1967 she married Philip Morse Vincent and they have four children. After the MSc, she spent three frustrating years trying to fractionate rat brain synaptosomes, until she was taken on by Ricardo Miledi FRS in the biophysics department to work on acetylcholine receptors. During her five years with Miledi, her medical background helped to establish a collaboration on myasthenia gravis with John Newsom-Davis (later FRS); together at the Royal Free Hospital, London, they created a neuroimmunology group that subsequently moved with Newsom-Davis to Oxford when he was appointed action research professor of neurology. After his retirement in 1998, Vincent led the group until 2016. During this time she was head of the department of clinical neurology (2005--2008) at the University of Oxford, president of the International Society of Neuroimmunology (2001--2004), and an associate editor of Brain (2004--2013). Her research group was initially located in the Weatherall Institute of Molecular Medicine at the John Radcliffe Hospital, working on a wide range of biological disciplines encompassing molecular biology, biochemistry, cellular immunology and intracellular neurophysiology. The group\'s research focused on autoimmune and genetic disorders of the neuromuscular junction, peripheral nerves and more recently the exciting field of central nervous system diseases. The principal autoimmune diseases studied were myasthenia gravis, the Lambert--Eaton myasthenic syndrome, limbic encephalitis, other types of autoimmune encephalitis and acquired neuromyotonia. Her contributions have been on the roles of antibodies directed against acetylcholine receptors and muscle specific kinase (MuSK) in myasthenia gravis, and glycine receptors or potassium channel-associated proteins LGI1, CASPR2 and Contactin-2 in CNS diseases. She demonstrated that transfer of antibodies across the placenta from the pregnant woman to the fetus in utero can cause both acute and longer-term neuromuscular and neurodevelopmental abnormalities. Since 2016 she has been emeritus Professor at Oxford University, emeritus Fellow of Somerville College, and holds an honorary appointment at UCL; she continues to work on neuromuscular disorders and advise young researchers. Her work in Oxford on brain disorders continues under Associate Professor Sarosh Irani and Dr Patrick Waters. She is a strong supporter of Freedom from Torture (formerly The Medical Foundation for Treatment of Torture Victims) and a Patron of British Pugwash (that brings together scientists and others concerned with international affairs and disarmament). ### Awards and honours {#awards_and_honours} In 2009, she presented the Leslie Oliver Oration at Queen\'s Hospital. In 2009, she received the medal of the Association of British Neurologists and in 2017, the World Federation of Neurology Scientific Contributions to Neurology award. In 2015, she was awarded the British Neuroscience Association Award for Outstanding Contribution to Neuroscience. In Cologne 2018, she was awarded with J Posner and J Dalmau, the International Prize for Translational Neuroscience of the Gertrud Reemtsma Foundation (formerly the Klaus Joachim Zülch Prize), and in Washington in 2019, the America Epilepsy Society Clinical Science Research Award (with J Dalmau). She received the Inaugural Distinguished Alumni Award, Imperial College, London, 2020 and the Life-time Award of the German Neurological Society (DGN) in 2021. In 2002, she was elected a Fellow of the Academy of Medical Sciences (FMedSci) and in 2011, a Fellow of the Royal Society (FRS).	2025-06-20T00:00:00
3,095	Amiga 500	\\| graphics = Denise \\| display = 736×567i 4 bpp (PAL)\ 736×483i 4 bpp (NTSC)\ 368×567i 6 bpp (PAL)\ 368×483i 6 bpp (NTSC) \\| sound = 4× 8-bit channels PCM at max. `{{nowrap\|28 [[kHz]]}}`{=mediawiki} with 6-bit volume in stereo \\| predecessor = Amiga 1000 \\| successor = `{{ubl\|[[Amiga 500 Plus]]\|[[Amiga 600]]}}`{=mediawiki} }} The Amiga 500, also known as the A500, was the first popular version of the Amiga home computer, \"redefining the home computer market and making so-called luxury features such as multitasking and colour a standard long before Microsoft or Apple sold these to the masses.\" It contains the same Motorola 68000 as the Amiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that of the Commodore 128. Commodore announced the Amiga 500 at the January 1987 winter Consumer Electronics Show`{{snd}}`{=mediawiki}at the same time as the high-end Amiga 2000. It was initially available in the Netherlands in April 1987, then the rest of Europe in May. In North America and the UK it was released in October 1987 with a `{{nowrap\|US$699/£499}}`{=mediawiki} list price. It competed directly against models in the Atari ST line. The Amiga 500 was sold in the same retail outlets as the Commodore 64, as opposed to the computer store-only Amiga 1000. It proved to be Commodore\'s best-selling model, particularly in Europe. Although popular with hobbyists, arguably its most widespread use was as a gaming machine, where its graphics and sound were of significant benefit. It was followed by a revised version of the computer, the Amiga 500 Plus, and the 500 series was discontinued in 1992. ## Releases In mid-1988, the Amiga 500 dropped its price from £499 to £399, and it was later bundled with the Batman Pack in the United Kingdom (from October 1989 to September 1990) which included the games Batman, F/A-18 Interceptor, The New Zealand Story and the bitmap graphics editor Deluxe Paint 2. Also included was the Amiga video connector which allows the A500 to be used with a conventional CRT television. In November 1991, the enhanced Amiga 500 Plus replaced the 500 in some markets. It was bundled with the Cartoon Classics pack in the United Kingdom at £399, although many stores still advertised it as an \'A500\'. The Amiga 500 Plus was virtually identical except for its new operating system, integrated 1MB of Chip memory, different \'trap-door\' expansion slot and slightly different keyboard, and in mid-1992, the two were discontinued and effectively replaced by the Amiga 600. In late 1992, Commodore released the Amiga 1200, a machine closer in concept to the original Amiga 500, but with significant technical improvements. Despite this, neither the A1200 nor the A600 replicated the commercial success of its predecessor. By this time, the home market was strongly shifting to IBM PC compatibles with VGA graphics and the low-cost Macintosh Classic, LC, and IIsi models. ## Description Outwardly resembling the Commodore 128 and codenamed \"Rock Lobster\" during development, the Amiga 500\'s base houses a keyboard and a CPU in one shell, unlike the Amiga 1000. The keyboard for Amiga 500s sold in the United States contains 94 keys, including ten function keys, four cursor keys, and a number pad. All European versions the keyboard have an additional two keys, except for the British variety, which still uses 94 keys. It uses a Motorola 68000 microprocessor running at `{{val\|7.15909 \|ul=MHz}}`{=mediawiki} in NTSC regions and `{{val\|7.09379 \|u=MHz}}`{=mediawiki} in PAL regions. The CPU implements a 32-bit model and has 32-bit registers, but it has a 16-bit main ALU and uses a 16-bit external data bus and a 24-bit address bus, providing a maximum of 16 MB of address space. Also built in to the base of the computer is a `{{frac\|3\|1\|2}}`{=mediawiki}-inch floppy disk drive. The user can also install up to three external floppy drives, either `{{frac\|3\|1\|2}}`{=mediawiki}- or `{{frac\|5\|1\|4}}`{=mediawiki}-inch, via the disk drive port. The second and third additional drives are installed by daisy-chaining them. Supported by these drives are double-sided disks with a capacity of 901,120 bytes, as well as 360- and 720-KB disks formatted for IBM PC compatibles. The earliest Amiga 500 models use nearly the same Original Amiga chipset as the Amiga 1000. So graphics can be displayed in multiple resolutions and color depths, even on the same screen. Resolutions vary from 320×200 (up to 32 colors) to 640×400 (up to 16 colors) for NTSC (704×484 overscan) and 320×256 to 640×512 for PAL (704×576 overscan.) The system uses planar graphics, with up to five bitplanes (four in high resolution) allowing 2-, 4-, 8-, 16-, and 32-color screens, from a palette of 4096 colors. Two special graphics modes are also available: Extra HalfBrite, which uses a sixth bitplane as a mask to cut the brightness of any pixel in half (resulting in 32 arbitrary colors plus 32 more colors set at half the value of the first 32), and Hold-And-Modify (HAM) which allows all 4096 colors to be used on screen simultaneously. Later revisions of the chipset are PAL/NTSC switchable in software. The sound chip produces four hardware-mixed channels, two to the left and two to the right, of 8-bit PCM at a sampling frequency up to `{{val\|28 \|ul=kHz}}`{=mediawiki}. Each hardware channel has its own independent volume level and sampling rate, and can be designated to another channel where it can modulate both volume and frequency using its own output. With DMA disabled it\'s possible to output with a sampling frequency up to `{{val\|56 \|u=kHz}}`{=mediawiki}. There is a common trick to output sound with 14-bit precision that can be combined to output 14-bit `{{val\|56 \|u=kHz}}`{=mediawiki} sound. The stock system comes with AmigaOS version 1.2 or 1.3 and `{{val\|512 \|u=KB}}`{=mediawiki} of chip RAM (150 ns access time), one built-in double-density standard floppy disk drive that is completely programmable and can read `{{val\|720 \|u=KB}}`{=mediawiki} IBM PC disks, `{{val\|880 \|u=KB}}`{=mediawiki} standard Amiga disks, and up to `{{nowrap\|984 KB}}`{=mediawiki} using custom-formatting drivers. Despite the lack of Amiga 2000-compatible internal expansion slots, there are many ports and expansion options. There are two DE9M Atari joystick ports for joysticks or mice, and stereo audio RCA connectors (1 V p-p). There is a floppy drive port for daisy-chaining up to three extra floppy disk drives via a DB23F connector. The then-standard RS-232 serial port (DB25M) and Centronics parallel port (DB25F) are also included. The power supply is (`{{val\|+5\|u=V}}`{=mediawiki}, `{{val\|p=±\|12\|u=V}}`{=mediawiki}). The system displays video in analog RGB `{{val\|50 \|ul=Hz}}`{=mediawiki} PAL or `{{val\|60 \|u=Hz}}`{=mediawiki} NTSC through a proprietary DB23M connector and in NTSC mode the line frequency is `{{val\|15.75 \|u=kHz}}`{=mediawiki} HSync for standard video modes, which is compatible with NTSC television and CVBS/RGB video, but out of range for most VGA-compatible monitors, while a multisync monitor is required for some of the higher resolutions. This connection can also be genlocked to an external video signal. The system was bundled with an RF adapter to provide output on televisions with a coaxial RF input, while monochrome video is available via an RCA connector (also coaxial). On the left side, behind a plastic cover, there is a Zorro (Zorro I) bus expansion external edge connector with 86 pins. Peripherals such as a hard disk drive can be added via the expansion slot and are configured automatically by the Amiga\'s AutoConfig standard, so that multiple devices do not conflict with each other. Up to `{{val\|8 \|u=MB}}`{=mediawiki} of so-called \"fast RAM\" (memory that can be accessed by the CPU only) can be added using the side expansion slot. This connector is electronically identical with the Amiga 1000\'s, but swapped on the other side. The Amiga 500 has a \"trap-door\" slot on the underside for a RAM upgrade (typically `{{val\|512 \|u=KB}}`{=mediawiki}). This extra RAM is classified as \"fast\" RAM, but is sometimes referred to as \"slow\" RAM: due to the design of the expansion bus, it is actually on the chipset bus. Such upgrades usually include a battery-backed real-time clock. All versions of the A500 can have the additional RAM configured as chip RAM by a simple hardware modification, which involves fitting a later model (8372A) Agnus chip. Likewise, all versions of the A500 can be upgraded to `{{val\|2 \|u=MB}}`{=mediawiki} chip RAM by fitting the `{{nowrap\|8372B Agnus}}`{=mediawiki} chip and adding additional memory. The Amiga 500 also sports an unusual feature for a budget machine, socketed chips, which allow easy replacement of defective chips. The CPU can be directly upgraded on the motherboard to a 68010; or to a 68020, 68030, or 68040 via the side expansion slot; or by removing the CPU and plugging a CPU expansion card into the CPU socket (this requires opening the computer and thus voided any remaining warranty). In fact, all the custom chips can be upgraded to the Amiga Enhanced Chip Set (ECS) versions. The plastic case is made of acrylonitrile butadiene styrene, or ABS. ABS degrades with time due to exposure to oxygen, causing a yellowing of the case. Other factors contributing to the degradation and yellowing include heat, shear, and ultraviolet light. The yellowing can be reversed by using an optical brightener, though without stabilizing agents or antioxidants to block oxygen, the yellowing will return. ## Technical specifications {#technical_specifications} - OCS (1.2 and 1.3 models) or ECS (1.3 and 500+ 2.04 models) chipset. ECS revisions of the chipset made PAL/NTSC mode switchable in software. - Sound: 4 hardware-mixed channels of 8-bit sound at up to `{{nowrap\|28 kHz}}`{=mediawiki}. The hardware channels have independent volumes (65 levels) and sampling rates, and are mixed down to two fully left and fully right stereo outputs. A software controllable low-pass audio filter is also included. - 512 KB of chip RAM (150 ns access time) - AmigaOS 1.2 or 1.3 (upgradeable up to 3.1.4 if 2 MB of RAM are installed) - One 3.5\" double-density floppy disk drive is built in, which is completely programmable and thus can read `{{nowrap\|720 KB}}`{=mediawiki} IBM PC disks, `{{nowrap\|880 KB}}`{=mediawiki} standard Amiga disks, and up to `{{nowrap\|984 KB}}`{=mediawiki} with custom formatting (such as Klaus Deppich\'s diskspare.device). Uses `{{nowrap\|300 rpm}}`{=mediawiki} (5 rotations/second) and `{{nowrap\|250 kbit/s}}`{=mediawiki}. - Built-in keyboard - A two-button mouse is included. ### Graphics - PAL mode: 768×580 maximum (overscan interlaced if viewed on composite monitor/TV). Typical resolutions: 320×256, 640×256 or 640×512 (all displayed with borders). - NTSC mode: 768×484 maximum (overscan interlaced if viewed on composite monitor/TV). Typical resolutions: 320×200, 640×200 or 640×400 (all displayed with borders). - Graphics can be of arbitrary dimensions, resolution and colour depth, even on the same screen. The Amiga can show multiple resolution modes at the same time, splitting the screen vertically. - Planar graphics are used, with up to five bitplanes (four in hires); this allowed 2, 4, 8, 16 and 32 colour screens, from a palette of 4096 colours. - Two special graphics modes are also included: - Extra Half Brite (EHB), which uses a sixth bitplane as a mask that halved the brightness of any colour seen - Hold-And-Modify (HAM), which allows all 4096 colours on screen at once. HAM makes it possible to use `{{nowrap\|12 bpp}}`{=mediawiki} over a `{{nowrap\|3 [[pixel]]}}`{=mediawiki} wide span. This works by letting each pixel position use the previous RGB value and modify one of the red, green or blue values to a new 4-bit value. This will cause some negligible colour artifacts however. ### Memory Using various expansion techniques, the A500\'s total RAM can reach up to 138 MB -- 2 MB Chip RAM, 8 MB 16-bit Fast RAM, and 128 MB 32-bit Fast RAM. #### Chip RAM {#chip_ram} The stock 512 KB Chip RAM can be complemented by 512 KB using a \"trapdoor\" expansion (Commodore A501 or compatible). While that expansion memory is connected to the chip bus, hardware limitations of early stock Agnus chip revisions prevent its use as Chip RAM, only the CPU can access it. Suffering from the same contention limitations as Chip RAM, that memory is known as \"Slow RAM\" or \"Pseudo-fast RAM\". Agnus revisions shipped with late A500 are ECS and allow use of trapdoor RAM as real Chip RAM for a total 1 MB. Additionally, several third-party expansions exist with up to 2 MB on the trapdoor board. Using a Gary adapter, that memory will be mapped as either split on Chip RAM and Slow RAM or fully as Slow RAM, depending on configuration. Furthermore, using an A3000 Agnus on an adapter board, it is possible to expand the Chip RAM to 2 MB, matching the A500+. #### Fast RAM {#fast_ram} \"Fast\" RAM is located on the CPU-side bus. Its access is exclusive to the CPU and not slowed by any chipset access. The side expansion port allows for up to 8 MB of Zorro-style expansion RAM. Alternatively, a CPU adapter allows for internal expansion. #### Accelerator RAM {#accelerator_ram} Internal or external CPU accelerators often include their own expansion memory. 16-bit CPUs are limited by the 24-bit address space but they can repurpose otherwise unused memory space for their included RAM. 32-bit CPU accelerators aren\'t limited by 24-bit addressing and can include up to 128 MB of Fast RAM (and potentially more). #### Memory map {#memory_map} Address Size in KB Description ----------- ------------ ----------------------------------------------------------------------- 0x00 0000 256 Chip RAM 0x04 0000 256 Chip RAM (A1000 option card) 0x08 0000 512 Chip RAM expansion 0x10 0000 1024 Extended Chip RAM for ECS/AGA 0x20 0000 8192 Primary auto-config space (Fast RAM) 0xA0 0000 1984 Reserved 0xBF D000 3.8 8520-B (even-byte addresses) 0xBF E001 3.8 8520-A (odd-byte addresses) 0xC0 0000 1536 Internal expansion memory (pseudo-fast, \"slow\" RAM on Amiga 500) 0xD8 0000 256 Reserved 0xDC 0000 64 Real time clock 0xDD 0000 188 Reserved 0xDF F000 4 Custom chip registers 0xE0 0000 512 Reserved 0xE8 0000 64 Zorro II auto-config space (before relocation) 0xE9 0000 448 Secondary auto-config space (usually 64K I/O boards) 0xF0 0000 512 512K System ROM (reserved for extended ROM image e.g. CDTV or CD^32^) 0xF8 0000 256 256K System ROM (Kickstart 2.04 or higher) 0xFC 0000 256 256K System ROM : Amiga system memory map ### Connectors - Two Atari joystick ports for joysticks or mice - Stereo audio RCA connectors (`{{val\|1\|u=V}}`{=mediawiki} p-p) - A floppy drive port (DB23F), for daisy-chaining up to 3 extra floppy disk drives via a DB23F connector - A standard RS-232 serial port (DB25M) - A parallel port (DB25F) - Power inlet (`{{val\|+5 \|u=V}}`{=mediawiki}, `{{val\|p=±\|12 \|u=V}}`{=mediawiki}) - Amiga video connector: Analogue RGB `{{val\|50\|ul=Hz}}`{=mediawiki} PAL and `{{val\|60 \|u=Hz}}`{=mediawiki} NTSC video output, provided on an Amiga-specific DB23M connector. Can drive video with `{{val\|15.75 \|u=kHz}}`{=mediawiki} HSync for standard Amiga video modes. This is not compatible with most VGA monitors. A Multisync monitor is required for some higher resolutions. This connection can also be genlocked to an external video signal. An RF adapter (A520) was frequently bundled with the machine to provide output on regular televisions or on composite monitors. A digital 16 colour Red-Green-Blue-Intensity signal is available too on the same connector. - Monochrome video via an RCA connector - Zorro II bus expansion on the left side behind a plastic cover - Trapdoor slot under the machine, for RAM expansion and real-time clock ### Expansions - Expansion ports are limited to a side expansion port and a trapdoor expansion on the underside of the machine. The casing can also be opened up (voiding the warranty), all larger chips are socketed rather than being TH/SMD soldered directly to the motherboard, so they can be replaced by hand. - The CPU can be upgraded to a Motorola 68010 directly or to a 68020, 68030 or 68040 via the side expansion slot or a CPU socket adapter board. - The chip RAM can be upgraded to `{{nowrap\|1 MB}}`{=mediawiki} directly on the motherboard, provided a Fat Agnus chip is also installed to support it. - Likewise, all the custom chips can be upgraded to the ECS chipset. - The A500+ model instead allowed upgrading by `{{nowrap\|1 MB}}`{=mediawiki} trapdoor chip RAM without clock, but there was no visible means on board to map any of this as FAST, causing incompatibility with some stubbornly coded programs. - There were modification instructions available for the A500 to solder or socket another `{{nowrap\|512 KB}}`{=mediawiki} RAM on the board, then run extra address lines to the trapdoor slot to accommodate an additional `{{nowrap\|1 MB}}`{=mediawiki} of fast or chip RAM depending on the installed chipset. - Up to `{{nowrap\|8 MB}}`{=mediawiki} of \"fast RAM\" can be added via the side expansion slot, even more if an accelerator with a non-EC (without reduced data/address bus) processor and 32-bit RAM is used. - Hard drive and other peripherals can be added via the side expansion slot. - Several companies provided combined CPU, memory and hard drive upgrades`{{snd}}`{=mediawiki}or provided chainable expansions that extended the bus as they were added`{{snd}}`{=mediawiki}as there is only one side expansion slot. - Expansions are configured automatically by AutoConfig software, so multiple pieces of hardware did not conflict with each other. ### Diagnostics When the computer is powered on a self-diagnostic test is run that will indicates failure with a specific colour: 1. Medium green means chip RAM is not found or is damaged. 2. Red means bad kickstart-ROM. 3. Yellow means the CPU has crashed (no trap routine or trying to run bad code) or a bad Zorro expansion card. 4. Blue means a custom chip problem (Denise, Paula, or Agnus). 5. Light green means CIA problem. 6. Light gray means that the CIA might be defective. 7. mean there is a ROM or CIA problem. 8. Black-only (no video) means there is no video output. The keyboard LED uses blink codes: 1. One blink means the keyboard ROM has a checksum error. 2. Two blinks means RAM failure. 3. Three blinks means watchdog timer failure. Measurements Overall (base): 6.2 cm x 47.4 cm x 33 cm; 2 7/16 in x 18 11/16 in x 13 in. ## Trap-door expansion 501 {#trap_door_expansion_501} A popular expansion for the Amiga 500 was the Amiga 501 circuit board that can be installed underneath the computer behind a plastic cover. The expansion contains `{{nowrap\|512 KB}}`{=mediawiki} RAM configured by default as \"Slow RAM\" or \"trap-door RAM\" and a battery-backed real-time clock (RTC). The 512 KB trap-door RAM and 512 KB of original chip RAM will result in 1 MB of total memory. The added memory is known as \"Slow RAM\", as its access is impacted by chip-bus bandwidth contention, while the chipset is not actually able to address it. Later revisions of the motherboard provide solder-jumpers to relocate the trap-door RAM to the chip memory pool, given the Agnus chip is the newer ECS version, shipped in later A500 motherboards. Newest (rev 8) A500s would share motherboard with A500+, and configure the expansion memory as CHIP by default. ## Software Each time the Amiga 500 is booted, it executes code from the Kickstart ROM. The Amiga 500 initially came shipped with AmigaOS 1.2, but units since October 1988 had version 1.3 installed. ## Reception and sales {#reception_and_sales} The Amiga 500 was the best-selling model in the Amiga family of computers. The German computer magazine Chip awarded the model the annual \"Home Computer of the Year\" title three consecutive times. At the European Computer Trade Show 1991, it also won the Leisure Award for the similar \"Home Computer of the Year\" title. Owing to the inexpensive cost of the Amiga 500 in then price-sensitive Europe, sales of the Amiga family of computers were strongest there, constituting 85 percent of Commodore\'s total sales in the fourth quarter of 1990. The Amiga 500 was widely perceived as a gaming machine and the Amiga 2000 a computer for artists and hobbyists. It has been claimed that Commodore sold as many as six million units worldwide. However, Commodore UK refuted that figure and said that the entire Amiga line sold between four and five million computers. Indeed, Ars Technica provides a year-by-year graph of the sales of all Amiga computers. The machine is reported to have sold 1,160,500 units in Germany (including Amiga 500 Plus sales). ## Amiga 500 Plus {#amiga_500_plus} The Amiga 500 Plus (often A500 Plus or simply A500+) is a revised version of the original Amiga 500 computer. The A500+ featured minor changes to the motherboard to make it cheaper to produce than the original A500. It was notable for introducing new versions of Kickstart and Workbench, and for some minor improvements in the custom chips, known as the Enhanced Chip Set (or ECS). Although officially introduced in 1992, some Amiga 500 units sold in late 1991 actually featured the revised motherboard used in the A500+. Although the Amiga 500+ was an improvement to the Amiga 500, it was minor. It was discontinued and replaced by the Amiga 600 in summer 1992, making it the shortest-lived Amiga model. ### Compatibility problems {#compatibility_problems} Due to the new Kickstart v2.04, quite a few popular games (such as Treasure Island Dizzy, Lotus Esprit Turbo Challenge, and SWIV) failed to work on the Amiga 500+, and some people took them back to dealers demanding an original Kickstart 1.3 Amiga 500. This problem was largely solved by third parties who produced Kickstart ROM switching boards, that could allow the Amiga 500+ to be downgraded to Kickstart 1.2 or 1.3. It also encouraged game developers to use better programming habits, which was important since Commodore already had plans for the introduction of the next-generation Amiga 1200 computer. A program, Relokick, was also released (and included with an issue of CU Amiga) which loaded a Kickstart 1.3 ROM image into memory and booted the machine into Kickstart 1.3, allowing most incompatible software to run (the software did take up 512 KB of system memory, meaning that some 1 MB only games would now fail for lack of available memory). In some cases, updated compatible versions of games were later released, such as budget versions of Lotus 1 and SWIV, and an update to Bubble Bobble. Double Dragon 2 by Binary Design received an update for ECS machines with the \"Amiga phase-alternated linescan version 4.01/ECS\". This solved compatibility issues with the graphics which appeared garbled on ECS machines, and it also slashed the in-game loading times from around 20 seconds to just over 6. ### Technical specifications {#technical_specifications_1} - Motorola 68000 CPU running at `{{nowrap\|7.09 MHz}}`{=mediawiki} (PAL) / `{{nowrap\|7.16 MHz}}`{=mediawiki} (NTSC), like its predecessor - 1 MB of Chip RAM (very early versions came with 512 KB) - Kickstart 2.04 (v37.175) - Workbench 37.67 (release 2.04) - Built-in battery backed RTC (Real Time Clock) - Full ECS chipset including new version of the Agnus chip and Denise chip	2025-06-20T00:00:00
3,104	Amiga 1000	The Amiga 1000, also known as the A1000, is the first personal computer released by Commodore International in the Amiga line. It combines the 16/32-bit Motorola 68000 CPU which was powerful by 1985 standards with one of the most advanced graphics and sound systems in its class. It runs a preemptive multitasking operating system that fits into `{{nowrap\|256 KB}}`{=mediawiki} of read-only memory and was shipped with 256 KB of RAM. The primary memory can be expanded internally with a manufacturer-supplied 256 KB module for a total of 512 KB of RAM. Using the external slot the primary memory can be expanded up to `{{nowrap\|8.5 MB.}}`{=mediawiki} ## Design The A1000 has a number of characteristics that distinguish it from later Amiga models: It is the only model to feature the short-lived Amiga check-mark logo on its case, the majority of the case is elevated slightly to give a storage area for the keyboard when not in use (a \"keyboard garage\"), and the inside of the case is engraved with the signatures of the Amiga designers (similar to the Macintosh); including Jay Miner and the paw print of his dog Mitchy. The A1000\'s case was designed by Howard Stolz. As Senior Industrial Designer at Commodore, Stolz was the mechanical lead and primary interface with Sanyo in Japan, the contract manufacturer for the A1000 casing. The Amiga 1000 was manufactured in two variations: One uses the NTSC television standard and the other uses the PAL television standard. The NTSC variant was the initial model manufactured and sold in North America. The later PAL model was manufactured in Germany and sold in countries using the PAL television standard. The first NTSC systems lack the EHB video mode which is present in all later Amiga models. Because AmigaOS was rather buggy at the time of the A1000\'s release, the OS was not placed in ROM then. Instead, the A1000 includes a daughterboard with 256 KB of RAM, dubbed the \"writable control store\" (WCS), into which the core of the operating system is loaded from floppy disk (this portion of the operating system is known as the \"Kickstart\"). The WCS is write-protected after loading, and system resets do not require a reload of the WCS. In Europe, the WCS was often referred to as WOM (Write Once Memory), a play on the more conventional term \"ROM\" (read-only memory). ## Technical information {#technical_information} The preproduction Amiga (which was codenamed \"Velvet\") released to developers in early 1985 contained `{{nowrap\|128 KB}}`{=mediawiki} of RAM with an option to expand it to `{{nowrap\|256 KB.}}`{=mediawiki} Commodore later increased the system memory to `{{nowrap\|256 KB}}`{=mediawiki} due to objections by the Amiga development team. The names of the custom chips were different; Denise and Paula were called Daphne and Portia respectively. The casing of the preproduction Amiga was almost identical to the production version: the main difference being an embossed Commodore logo in the top left corner. It did not have the developer signatures. The Amiga 1000 has a Motorola 68000 CPU running at 7.15909 MHz on NTSC systems or 7.09379 MHz on PAL systems, precisely double the video color carrier frequency for NTSC or 1.6 times the color carrier frequency for PAL. The system clock timings are derived from the video frequency, which simplifies glue logic and allows the Amiga 1000 to make do with a single crystal. In keeping with its video game heritage, the chipset was designed to synchronize CPU memory access and chipset DMA so the hardware runs in real time without wait-state delays. Though most units were sold with an analog RGB monitor, the A1000 also has a built-in composite video output which allows the computer to be connected directly to some monitors other than their standard RGB monitor. The A1000 also has a \"TV MOD\" output, into which an RF Modulator can be plugged, allowing connection to older televisions that did not have a composite video input. The original 68000 CPU can be directly replaced with a Motorola 68010, which can execute instructions slightly faster than the 68000 but also introduces a small degree of software incompatibility. Third-party CPU upgrades, which mostly fit in the CPU socket, use faster 68020 or 68030 microprocessors and integrated memory, as well as provide support for a 68881 or 68882 FPU. Such upgrades often have the option to revert to 68000 mode for full compatibility. Some boards have a socket to seat the original 68000, whereas the 68030 cards typically come with an on-board 68000. The original Amiga 1000 is the only model to have 256 KB of Amiga Chip RAM, which can be expanded to 512 KB with the addition of a daughterboard under a cover in the center front of the machine. RAM may also be upgraded via official and third-party upgrades, with a practical upper limit of about 9 MB of \"fast RAM\" due to the 68000\'s 24-bit address bus. This memory is accessible only by the CPU permitting faster code execution as DMA cycles are not shared with the chipset. The Amiga 1000 features an 86-pin expansion port (electrically identical to the later Amiga 500 expansion port, though the A500\'s connector is inverted). This port is used by third-party expansions such as memory upgrades and SCSI adapters. These resources are handled by the Amiga Autoconfig standard. Other expansion options are available including a bus expander which provides two Zorro-II slots. ### Specifications +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Attribute \| Specification \| +====================+=================================================================================================================================================================+ \| Processor \| Motorola 68000 at 7.16 MHz (NTSC) or 7.09 MHz (PAL) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| RAM \| 256 KB of Amiga Chip RAM; upgradeable to 512 KB by dedicated cartridge; max. 8 MB Fast RAM with external cartridge \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| ROM \| 8 KB bootstrap ROM. 256 KB WCS reserved for OS (loaded from the Kickstart floppy disk at power-on) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Chipset \| Original Chip Set (OCS) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Video \| 12-bit color palette (4096 colors). Graphic modes with up to 32, 64 (EHB mode; Early NTSC models do not have the EHB mode) or 4096 (HAM mode) on-screen colors: \| \| \| \| \| \| - 320×200 to 320×400i (NTSC) \| \| \| - 320×256 to 320×512i (PAL) \| \| \| \| \| \| Graphic modes with up to 16 on-screen colors: \| \| \| \| \| \| - 640×200 to 640×400i (NTSC) \| \| \| - 640×256 to 640×512i (PAL) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Audio \| 4× 8-bit PCM channels (2 stereo channels); 28 kHz maximum DMA sampling rate; 70 dB S/N ratio \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Removable storage \| 3.5-inch DD floppy disk drive (880 KB capacity) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Audio/video out \| Analog RGB video out (DB-23M); TV MOD audio/video output (for Amiga RF modulator TV connection); Composite video out (RCA); Audio out (2× RCA) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Input/output ports \| Keyboard port (RJ10); 2× mouse/gamepad ports (DE9); RS-232 serial port (DB-25F); Centronics style parallel port (DB-25M); floppy disk drive port (DB-23F) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Expansion slots \| 86-pin expansion port \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ \| Operating system \| AmigaOS 1 (Kickstart 1.0/1.1/1.2/1.3 and Workbench 1.0/1.1/1.2/1.3) \| +--------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ ## Retail Introduced on July 23, 1985, during a star-studded gala featuring Andy Warhol and Debbie Harry held at the Vivian Beaumont Theater at Lincoln Center in New York City, machines began shipping in September with a base configuration of 256 KB of RAM at the retail price of `{{US$\|1,295}}`{=mediawiki}. A 13 in analog RGB monitor was available for around `{{US$\|300}}`{=mediawiki}, bringing the price of a complete Amiga system to US\$1,595 (`{{Inflation\|US\|1595\|1985\|fmt=eq\|r=-1}}`{=mediawiki}). Before the release of the Amiga 500 and Amiga 2000 models in 1987, the A1000 was marketed as simply the Amiga, although the model number was there from the beginning, as the original box indicates. In the US, the A1000 was marketed as The Amiga from Commodore, with the Commodore logo omitted from the case. The Commodore branding was retained for the international versions. Additionally, the Amiga 1000 was sold exclusively in computer stores in the US rather than the various non computer-dedicated department and toy stores through which the VIC-20 and Commodore 64 were retailed. These measures were an effort to avoid Commodore\'s \"toy-store\" computer image created during the Tramiel era. Along with the operating system, the machine came bundled with a version of AmigaBASIC developed by Microsoft and a speech synthesis library developed by Softvoice, Inc. ## Aftermarket upgrades {#aftermarket_upgrades} Many A1000 owners remained attached to their machines long after newer models rendered the units technically obsolete, and it attracted numerous aftermarket upgrades. Many CPU upgrades that plugged into the Motorola 68000 socket functioned in the A1000. Additionally, a line of products called the Rejuvenator series allowed the use of newer chipsets in the A1000, and an Australian-designed replacement A1000 motherboard called The Phoenix utilized the same chipset as the A3000 and added an A2000-compatible video slot and on-board SCSI controller. ## Reception and impact {#reception_and_impact} In its product preview, Byte magazine was impressed by the computer\'s multitasking capabilities and the quality of its graphics and sound systems. It also praised its text-to-speech library for voice output, and predicted that the Amiga would be successful enough to influence the personal computer industry. The Amiga 1000 was released to positive reviews. Compute! lauded it as an inexpensive, truly general-purpose computer that might break preconceptions dividing the microcomputer marketplace. In this case, it was capable of outperforming most business, as well as arcade game machines and delivering sampled sound, making it suitable for offices, gamers, and digital artists. Computer Gaming World praised the machine\'s versatility without any obvious hardware shortcomings and stressed that it was ideal for game designers demanding fewer system constraints. Creative Computing magazine had only minor criticisms for what they otherwise called a \"dream machine.\" These criticisms were directed toward its case quality, the disk drives slowing during certain operations, and not finding an `AUTOEXEC` command in AmigaDOS, though the marketing vice president of Commodore, Clive Smith, assured the magazine that later production units would address most of its complaints. Months after the Amiga 1000 was released, InfoWorld offered a mixed review. It praised Intuition and the customizability of Workbench, but took issue with the operating system\'s bugs such as memory overflow and screen flickering of single lines as a result of their being interleaved when displayed in high resolution mode. It also criticized the sparseness of the software library preventing the publication from fully realizing the computer\'s potential. In 1994, as Commodore filed for bankruptcy, Byte magazine called the Amiga 1000 \"the first multimedia computer\... so far ahead of its time that almost nobody---including Commodore\'s marketing department---could fully articulate what it was all about\". In 2006, PC World rated the Amiga 1000 as the 7th greatest PC of all time. In 2007, it was rated by the same magazine as the 37th best tech product of all time. Also that year, IDG Sweden ranked it the 10th best computer of all time. ## Joe Pillow {#joe_pillow} \"Joe Pillow\" was the name given on the ticket for the extra airline seat purchased to hold the first Amiga prototype while on the way to the January 1984 Consumer Electronics Show. The airlines required a name for the airline ticket and Joe Pillow was born. The engineers (RJ Mical and Dale Luck) who flew with the Amiga prototype (codenamed Lorraine) drew a happy face on the front of the pillowcase and even added a tie. Joe Pillow extended his fifteen minutes of fame when the Amiga went to production. All fifty-three Amiga team members who worked on the project signed the Amiga case. This included Joe Pillow and Jay Miner\'s dog Michy who each got to \"sign\" the case in their own unique way.	2025-06-20T00:00:00
3,112	Arianespace	$2021$ \\| operating_income = \\| net_income = \\| assets = \\| equity = \\| owner = \\| num_employees = 220 (2023) \\| parent = ArianeGroup \\| divisions = \\| subsid = \\| homepage = `{{URL\|arianespace.com}}`{=mediawiki} \\| footnotes = \\| intl = \\| location_city = Évry-Courcouronnes n. Paris \\| location_country = France \\| location = \\| locations = \\| caption = }} Arianespace SA is a French company founded in March 1980 as the world\'s first commercial launch service provider. It operates two launch vehicles: Vega C, a small-lift rocket, and Ariane 6, a medium-to-heavy-lift rocket. Arianespace is a subsidiary of ArianeGroup, a joint venture between Airbus and Safran. European space launches are carried out as a collaborative effort between private companies and government agencies. The role of Arianespace is to market Ariane 6 launch services, prepare missions, and manage customer relations. At the Guiana Space Centre (CSG) in French Guiana, the company oversees the team responsible for integrating and preparing launch vehicles. The rockets themselves are designed and manufactured by other companies: ArianeGroup for the Ariane 6 and Avio for the Vega. The launch infrastructure at the CSG is owned by the European Space Agency, while the land itself belongs to and is managed by CNES, the French national space agency. , Arianespace had launched more than 850 satellites in 287 missions spanning 41 years. The company\'s first commercial launch was Spacenet 1, which took place on 23 May 1984. In addition to its facilities at the CSG, the company\'s main offices are in Évry-Courcouronnes, a suburb of Paris. ## History The formation of Arianespace SA is closely associated with the desire of several European nations to pursue joint collaboration in the field of space exploration and the formation of a pan-national organisation, the European Space Agency (ESA), to oversee such undertaking during 1973. Prior to the ESA\'s formation, France had been lobbying for the development of a new European expendable launch system to serve as a replacement for the Europa rocket. Accordingly, one of the first programmes launched by the ESA was the Ariane heavy launcher. The express purpose of this launcher was to facilitate the delivery of commercial satellites into geosynchronous orbit. France was the largest stakeholder in the Ariane development programme. French aerospace manufacturer Aérospatiale served as the prime contractor and held responsibility for performing the integration of all sections of the vehicle, while French engine manufacturer Société Européenne de Propulsion (SEP) provided the first, second and third stage engines (the third stage engines were produced in partnership with German aerospace manufacturer MBB). Other major companies involved included the French firms Air Liquide and Matra, Swedish manufacturer Volvo, and German aircraft producer Dornier Flugzeugwerke. Development of the third stage was a major focus point for the project - prior to Ariane, only the United States had ever flown a launcher that utilised hydrogen-powered upper stages. Immediately following the successful first test launch of an Ariane 1 on 24 December 1979, the French space agency Centre national d\'études spatiales (CNES) and the ESA created a new company, Arianespace, for the purpose of promoting, marketing, and managing Ariane operations. According to Arianespace, at the time of its establishment, it was the world\'s first launch services company. Following a further three test launches, the first commercial launch took place on 10 September 1982, which ended in failure as a result of a turbopump having failed in the third stage. The six remaining flights of the Ariane 1 were successful, with the final flight occurring during February 1986. As a result of these repeated successes, orders for the Ariane launcher quickly mounted up; by early 1984, a total of 27 satellites had been booked to use Ariane, which was estimated to be half of the world\'s market at that time. As a result of the commercial success, after the tenth Ariane mission was flown, the ESA formally transferred responsibility for Ariane over to Arianespace. By early 1986, the Ariane 1, along with its Ariane 2 and Ariane 3 derivates, were the dominant launcher on the world market. The Ariane 2 and Ariane 3 were short-lived platforms while the more extensive Ariane 4 was being developed; it was a considerably larger and more flexible launcher that the earlier members of its family, having been intended from the onset to compete with the upper end of launchers worldwide. In comparison, while the Ariane 1 had a typical weight of 207 tonnes and could launch payloads of up to 1.7 tonnes into orbit; the larger Ariane 4 had a typical weight of 470 tonnes and could orbit payloads of up to 4.2 tonnes. Despite this, the Ariane 4 was actually 15 per cent smaller than the Ariane 3. On 15 June 1988, the first successful launch of the Ariane 4 was conducted. This maiden flight was considered a success, having placed multiple satellites into orbit. For the V50 launch onwards, an improved third stage, known as the H10+, was adopted for the Ariane 4, which raised the rocket\'s overall payload capacity by 110 kg and increased its burn time by 20 seconds. Even prior to the first flight of the Ariane 4 in 1988, development of a successor, designated as the Ariane 5, had already commenced. In January 1985, the Ariane 5 was officially adopted as an ESA programme, and began an eleven-year development and test program to the first launch in 1996. It lacked the high levels of commonality that the Ariane 4 had with its predecessors, and had been designed not only for launching heavier payloads of up to 5.2 tonnes and at a 20 per cent cost reduction over the Ariane 4, but for a higher margin of safety due to the fact that the Ariane 5 was designed to conduct crewed space launches as well, being intended to transport astronauts using the proposed Hermes space vehicle. Development of the Ariane 5 was not without controversy as some ESA members considered the mature Ariane 4 platform to be more suited for meeting established needs for such launchers; it was reportedly for this reason that Britain chose not to participate in the Ariane 5 programme. For several years, Ariane 4 and Ariane 5 launchers were operated interchangeably; however, it was eventually decided to terminate all Ariane 4 operations in favour of concentrating on the newer Ariane 5. During the mid-1990s, French firms Aérospatiale and SEP, along with Italian firm Bombrini-Parodi-Delfino (BPD), held discussions on the development of a proposed Ariane Complementary Launcher (ACL). Simultaneously, Italy championed the concept of a new solid-propellant satellite launcher, referred to as Vega. During March 2003, contracts for Vega\'s development were signed by the ESA and CNES; Italy provided 65 per cent of funding while six additional nations contributed the remainder. In May 2004, it was reported that a contract was signed between commercial operator Arianespace and prime contractor ELV to perform vehicle integration at Kourou, French Guiana. On 13 February 2012, the first launch of the Vega took place; it was reported as being an \"apparently perfect flight\". Since entering commercial service, Arianespace markets Vega as a launch system tailored for missions to polar and Sun-synchronous orbits. During 2002, the ESA announced the Arianespace Soyuz programme in cooperation with Russia; a launch site for Soyuz was constructed as the Guiana Space Centre, while the Soyuz launch vehicle was modified for use at the site. On 4 February 2005, both funding and final approval for the initiative were granted. Arianespace had offered launch services on the modified Soyuz ST-B to its clients. On 21 October 2011, Arianespace launched the first Soyuz rocket ever from outside former Soviet territory. The payload consisted of two Galileo navigation satellites. Since 2011, Arianespace has ordered a total of 23 Soyuz rockets, enough to cover its needs until 2019 at a pace of three to four launches per year. On 21 January 2019, ArianeGroup and Arianespace announced that it had signed a one-year contract with the ESA to study and prepare for a mission to the Moon to mine regolith. In 2020, Arianespace suspended operations for nearly two months due to the COVID-19 pandemic. Operations were suspended on 18 March and are, as of 29 April, expected to resume on 11 May. The return to operations will observe a number of new health and safety guidelines including social distancing in the workplace. In 2023, Ariane 5 was retired with the introduction of new Ariane 6, that conducted its maiden flight on 9 July 2024. In August 2024, the ESA agreed to allow Avio---the prime contractor for the ESA-funded Vega---to directly commercialize Vega C and seek non-governmental customers. Arianespace had handled marketing of Vega launches prior to that time. The transition is anticipated to be complete by the end of 2025. ## Company and infrastructure {#company_and_infrastructure} Arianespace \"is the marketing and sales organization for the European space industry and various component suppliers.\" The primary shareholders of Arianespace are its suppliers,`{{why\|date=September 2019}}`{=mediawiki} in various European nations. Arianespace had 24 shareholders in 2008, 21 in 2014, and just 17 `{{as of\|October 2018\|lc=y}}`{=mediawiki}. Country scope=\"col\" data-sort-type=\"number\"\\|Total share Shareholder scope=\"col\" data-sort-type=\"number\"\\|Capital --------- ------------------------------------------------------ ---------------------------------- -------------------------------------------------- 3.36% SABCA 2.71% Thales Alenia Space Belgium 0.33% 0.32% 64.10% ArianeGroup 62.10% Air Liquide SA 1.89% 0.11% CIE Deutsche \<0.01% 19.85% ArianeGroup 11.59% AG 8.26% 3.38% Avio S.p.A. 3.38% 1.94% Airbus Defence and Space B.V. 1.94% 0.11% Kongsberg Defence & Aerospace AS 0.11% 2.14% Airbus Defence and Space SAU 2.03% CRISA 0.11% 2.45% GKN Aerospace Sweden AB 1.63% RUAG Space AB 0.82% 2.67% RUAG Schweiz AG 2.67% In 2015, Arianespace shareholding was restructured due to the creation of Airbus Safran Launchers (later renamed ArianeGroup), which is tasked with developing and manufacturing the Ariane 6 carrier rocket. Industrial groups Airbus and Safran pooled their shares along with the French government\'s CNES stake to form a partnership company holding just under 74% of Arianespace shares, while the remaining 26% is spread across suppliers in nine countries including further Airbus subsidiaries. ## Competition and pricing {#competition_and_pricing} By 2004, Arianespace reportedly held more than 50% of the world market for boosting satellites to geostationary transfer orbit (GTO). During the 2010s, the disruptive force represented by the new sector entrant SpaceX forced Arianespace to cut back on its workforce and focus on cost-cutting to decrease costs to remain competitive against the new low-cost entrant in the launch sector. In the midst of pricing pressure from such companies, during November 2013, Arianespace announced that it was enacting pricing flexibility for the \"lighter satellites\" that it carries to Geostationary orbits aboard its Ariane 5. According to Arianespace\'s managing director: \"It\'s quite clear there\'s a very significant challenge coming from SpaceX (\...) therefore things have to change (\...) and the whole European industry is being restructured, consolidated, rationalised and streamlined.\" During early 2014, Arianespace was considering requesting additional subsidies from European governments to face competition from SpaceX and unfavorable changes in the Euro-Dollar exchange rate. The company had halved subsidy support by €100m per year since 2002 but the fall in the value of the US Dollar meant Arianespace was losing €60m per year due to currency fluctuations on launch contracts. SpaceX had reportedly begun to take market share from Arianespace, Eutelsat CEO Michel de Rosen, a major customer of Arianespace, stated that: \"Each year that passes will see SpaceX advance, gain market share and further reduce its costs through economies of scale.\" By September 2014, Arianespace had reportedly to sign four additional contracts for lower slots on an Ariane 5 SYLDA dispenser for satellites that otherwise could be flown on a SpaceX launch vehicle; this was claimed to have been allowed via cost reductions; it had signed a total of 11 contracts by that point, while two additional ones that were under advanced negotiations. At the time, Arianespace has a backlog of launches worth `{{Euro\|4.5}}`{=mediawiki} billion with 38 satellites to be launched on Ariane 5, 7 on Soyuz and 9 on Vega, claiming 60% of the global satellite launch market. However, since 2017, Arianespace\'s market share has been passed by SpaceX in commercial launches. ## Launch vehicles {#launch_vehicles} Currently, Arianespace operates three launch vehicles: Name Payload to LEO/SSO Payload to GTO ----------- -------------------- ---------------- Vega C Ariane 62 Ariane 64 ### Ariane launch vehicles {#ariane_launch_vehicles} Since the first launch in 1979, there have been several versions of the Ariane launch vehicle: - Ariane 1, first successful launch on 24 December 1979 - Ariane 2, first successful launch on 20 November 1987 (the first launch on 30 May 1986, failed) - Ariane 3, first successful launch on 4 August 1984 - Ariane 4, first successful launch on 15 June 1988 - Ariane 5, first successful launch on 30 October 1997 (the first launch on 4 June 1996, failed). - Ariane 6, It has a similar payload capacity to that of Ariane 5 but considerably lower costs. Its first flight took place on 9 July 2024. - Ariane Next, in early development. It will be a partially reusable launcher that should succeed Ariane 6 from the 2030s. The objective of this reusable launcher is to halve the launch costs.	2025-06-20T00:00:00
3,116	Accumulator (computing)	`{{more citations needed\|date=February 2024}}`{=mediawiki} In a computer\'s central processing unit (CPU), the accumulator is a register in which intermediate arithmetic logic unit results are stored. Without a register like an accumulator, it would be necessary to write the result of each calculation (addition, multiplication, shift, etc.) to cache or main memory, perhaps only to be read right back again for use in the next operation. Accessing memory is slower than accessing a register like an accumulator because the technology used for the large main memory is slower (but cheaper) than that used for a register. Early electronic computer systems were often split into two groups, those with accumulators and those without. Modern computer systems often have multiple general-purpose registers that can operate as accumulators, and the term is no longer as common as it once was. However, to simplify their design, a number of special-purpose processors still use a single accumulator. ## Basic concept {#basic_concept} Mathematical operations often take place in a stepwise fashion, using the results from one operation as the input to the next. For instance, a manual calculation of a worker\'s weekly payroll might look something like: 1. look up the number of hours worked from the employee\'s time card 2. look up the pay rate for that employee from a table 3. multiply the hours by the pay rate to get their basic weekly pay 4. multiply their basic pay by a fixed percentage to account for income tax 5. subtract that number from their basic pay to get their weekly pay after tax 6. multiply that result by another fixed percentage to account for retirement plans 7. subtract that number from their basic pay to get their weekly pay after all deductions A computer program carrying out the same task would follow the same basic sequence of operations, although the values being looked up would all be stored in computer memory. In early computers, the number of hours would likely be held on a punch card and the pay rate in some other form of memory, perhaps a magnetic drum. Once the multiplication is complete, the result needs to be placed somewhere. On a \"drum machine\" this would likely be back to the drum, an operation that takes considerable time. Then the very next operation has to read that value back in, which introduces another considerable delay. Accumulators dramatically improve performance in systems like these by providing a scratchpad area where the results of one operation can be fed to the next one for little or no performance penalty. In the example above, the basic weekly pay would be calculated and placed in the accumulator, which could then immediately be used by the income tax calculation. This removes one save and one read operation from the sequence, operations that generally took tens to hundreds of times as long as the multiplication itself. ## Accumulator machines {#accumulator_machines} An accumulator machine, also called a 1-operand machine, or a CPU with accumulator-based architecture, is a kind of CPU where, although it may have several registers, the CPU mostly stores the results of calculations in one special register, typically called \"the accumulator\". Almost all `{{clarify\|text=early\|reason=To what years does "early" refer\|date=July 2021}}`{=mediawiki} computers were accumulator machines with only the high-performance \"supercomputers\" having multiple registers. Then as mainframe systems gave way to microcomputers, accumulator architectures were again popular with the MOS 6502 being a notable example. Many 8-bit microcontrollers that are still popular `{{as of\|2014\|lc=y}}`{=mediawiki}, such as the PICmicro and 8051, are accumulator-based machines. Modern CPUs are typically 2-operand or 3-operand machines. The additional operands specify which one of many general-purpose registers (also called \"general-purpose accumulators\") are used as the source and destination for calculations. These CPUs are not considered \"accumulator machines\". The characteristic that distinguishes one register as being the accumulator of a computer architecture is that the accumulator (if the architecture were to have one) would be used as an implicit operand for arithmetic instructions. For instance, a CPU might have an instruction like: `ADD ``memaddress` that adds the value read from memory location memaddress to the value in the accumulator, placing the result back in the accumulator. The accumulator is not identified in the instruction by a register number; it is implicit in the instruction and no other register can be specified in the instruction. Some architectures use a particular register as an accumulator in some instructions, but other instructions use register numbers for explicit operand specification. ## History of the computer accumulator {#history_of_the_computer_accumulator} Any system that uses a single \"memory\" to store the result of multiple operations can be considered an accumulator. J. Presper Eckert refers to even the earliest adding machines of Gottfried Leibniz and Blaise Pascal as accumulator-based systems. Percy Ludgate was the first to conceive a multiplier-accumulator (MAC) in his Analytical Machine of 1909. Historical convention dedicates a register to \"the accumulator\", an \"arithmetic organ\" that literally accumulates its number during a sequence of arithmetic operations: : \"The first part of our arithmetic organ \... should be a parallel storage organ which can receive a number and add it to the one already in it, which is also able to clear its contents and which can store what it contains. We will call such an organ an Accumulator. It is quite conventional in principle in past and present computing machines of the most varied types, e.g. desk multipliers, standard IBM counters, more modern relay machines, the ENIAC\" (Goldstine and von Neumann, 1946; p. 98 in Bell and Newell 1971). Just a few of the instructions are, for example (with some modern interpretation): - Clear accumulator and add number from memory location X - Clear accumulator and subtract number from memory location X - Add number copied from memory location X to the contents of the accumulator - Subtract number copied from memory location X from the contents of the accumulator - Clear accumulator and shift contents of register into accumulator No convention exists regarding the names for operations from registers to accumulator and from accumulator to registers. Tradition (e.g. Donald Knuth\'s (1973) hypothetical MIX computer), for example, uses two instructions called load accumulator from register/memory (e.g. \"LDA r\") and store accumulator to register/memory (e.g. \"STA r\"). Knuth\'s model has many other instructions as well. ## Notable accumulator-based computers {#notable_accumulator_based_computers} The 1945 configuration of ENIAC had 20 accumulators, which could operate in parallel. Each one could store an eight decimal digit number and add to it (or subtract from it) a number it received. Most of IBM\'s early binary \"scientific\" computers, beginning with the vacuum tube IBM 701 in 1952, used a single 36-bit accumulator, along with a separate multiplier/quotient register to handle operations with longer results. The IBM 650, a decimal machine, had one 10 digit distributor and two ten-digit accumulators; the IBM 7070, a later, transistorized decimal machine had three accumulators. The IBM System/360, and Digital Equipment Corporation\'s PDP-6, had 16 general-purpose registers, although the PDP-6 and its successor, the PDP-10, call them accumulators. The 12-bit PDP-8 was one of the first minicomputers to use accumulators, and inspired many later machines. The PDP-8 had but one accumulator. The HP 2100 and Data General Nova had 2 and 4 accumulators. The Nova was created when this follow-on to the PDP-8 was rejected in favor of what would become the PDP-11. The Nova provided four accumulators, AC0-AC3, although AC2 and AC3 could also be used to provide offset addresses, tending towards more generality of usage for the registers. The PDP-11 had 8 general-purpose registers, along the lines of the System/360 and PDP-10; most later CISC and RISC machines provided multiple general-purpose registers. Early 4-bit and 8-bit microprocessors such as the 4004, 8008 and numerous others, typically had single accumulators. The 8051 microcontroller has two, a primary accumulator and a secondary accumulator, where the second is used by instructions only when multiplying (MUL AB) or dividing (DIV AB); the former splits the 16-bit result between the two 8-bit accumulators, whereas the latter stores the quotient on the primary accumulator A and the remainder in the secondary accumulator B. As a direct descendant of the 8008, the 8080, and the 8086, the modern ubiquitous Intel x86 processors still uses the primary accumulator EAX and the secondary accumulator EDX for multiplication and division of large numbers. For instance, MUL ECX will multiply the 32-bit registers ECX and EAX and split the 64-bit result between EAX and EDX. However, MUL and DIV are special cases; other arithmetic-logical instructions (ADD, SUB, CMP, AND, OR, XOR, TEST) may specify any of the eight registers EAX, ECX, EDX, EBX, ESP, EBP, ESI, EDI as the accumulator (i.e. left operand and destination). This is also supported for multiply if the upper half of the result is not required. x86 is thus a fairly general register architecture, despite being based on an accumulator model. The 64-bit extension of x86, x86-64, has been further generalized to 16 instead of 8 general registers.	2025-06-20T00:00:00
3,120	Andersonville, Georgia	Andersonville is a city in Sumter County, Georgia, United States. As of the 2020 census, the city had a population of 237. It is located in the southwest part of the state, approximately 60 mi southwest of Macon on the Central of Georgia railroad. During the American Civil War, it was the site of a prisoner-of-war camp, which is now Andersonville National Historic Site. Andersonville is part of the Americus micropolitan statistical area. ## History The hamlet of Anderson was named for John Anderson, a director of the South Western Railroad in 1853 when it was extended from Oglethorpe to Americus. It was known as Anderson Station until the US post office was established in November 1855. The government changed the name of the station from \"Anderson\" to \"Andersonville\" in order to avoid confusion with the post office in Anderson, South Carolina. During the Civil War, the Confederate army established Camp Sumter at Andersonville to house incoming Union prisoners of war. The overcrowded Andersonville Prison was notorious for its bad conditions, and nearly 13,000 prisoners died there. After the war, Henry Wirz was convicted for war crimes related to the command of the camp. His trial was later regarded as unfair by several pro-confederacy groups, and a monument in his honor has been erected in Andersonville by the United Daughters of the Confederacy. The town also served as a supply depot during the war period. It included a post office, a depot, a blacksmith shop and stable, a couple of general stores, two saloons, a school, a Methodist church, and about a dozen houses. Ben Dykes, who owned the land on which the prison was built, was both depot agent and postmaster. Until the establishment of the prison, the area was entirely dependent on agriculture, supported by dark reddish brown sandy loams later mapped as Greenville and Red Bay soil series. After the close of the prison and end of the war, the town continued economically dependent on agriculture, primarily the cultivation of cotton as a commodity crop. It was not until 1968, when the large-scale mining of kaolin, bauxitic kaolin, and bauxite was begun by Mulcoa, Mullite Company of America, that the town was dramatically altered. This operation exploited 2000 acre of scrub oak wilderness into a massive mining and refining operation. The company now`{{When\|date=April 2023}}`{=mediawiki} ships more than 2000 tons of refined ore from Andersonville each week. In 1974, long-time mayor Lewis Easterlin and a group of concerned citizens decided to promote tourism in the town, redeveloping Main Street to look much as it did during the American Civil War. The city of Andersonville and the Andersonville National Historic Site, location of the prison camp, are now tourist attractions. ## Geography ### Climate ## Demographics As of the census of 2000, there were 331 people, 124 households, and 86 families residing in the city. The population density was 254.1 PD/sqmi. There were 142 housing units at an average density of 109.0 /sqmi. The racial makeup of the city was 65.26% White and 34.74% African American. Hispanic or Latino of any race were 1.21% of the population. There were 124 households, out of which 34.7% had children under the age of 18 living with them, 46.0% were married couples living together, 17.7% had a female householder with no husband present, and 30.6% were non-families. 26.6% of all households were made up of individuals, and 10.5% had someone living alone who was 65 years of age or older. The average household size was 2.67 and the average family size was 3.21. In the city, the population was spread out, with 27.8% under the age of 18, 9.4% from 18 to 24, 31.4% from 25 to 44, 19.3% from 45 to 64, and 12.1% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 105.6 males. For every 100 females age 18 and over, there were 97.5 males. The median income for a household in the city was \$29,107, and the median income for a family was \$30,972. Males had a median income of \$26,591 versus \$20,000 for females. The per capita income for the city was \$15,168. About 19.8% of families and 23.0% of the population were below the poverty line, including 29.3% of those under age 18 and 13.5% of those age 65 or over.	2025-06-20T00:00:00
3,122	Agra Canal	The Agra Canal is an important Indian irrigation work which starts from Okhla in Delhi. The Agra canal originates at the Okhla barrage, downstream of Nizamuddin bridge. The canal receives its water from the Yamuna River at Okhla, about 10 km to the south of New Delhi. The weir across the Yamuna was constructed of locally quarried stone. It was about 800 yd long, and rises seven feet above the summer level of the river. From Okhla the canal follows a route south then southeast for 140 miles in the high land between the Khari-Nadi and the Yamuna and finally joins the Utanga River about 27 miles below Agra. Navigable branches connect the canal with Mathura and Agra. The canal irrigates about {{lakh 1.5}} in Agra, and Mathura in Uttar Pradesh, Faridabad in Haryana, Bharatpur in Rajasthan and also some parts of Delhi. ## History The canal opened in the year 1874. In the beginning, it was available for navigation, in Delhi, erstwhile Gurgaon, Mathura and Agra Districts, and Bharatpur State. Later, navigation was stopped in 1904 and the canal has, since then, been exclusively used for irrigation purposes only. At present, the canal does not flow in Gurgaon district, but only in Faridabad, which was earlier a part of Gurgaon. In recent times, Agra canal is an important landmark which separates Greater Faridabad from Faridabad.	2025-06-20T00:00:00
3,124	Afterglow	An afterglow in meteorology consists of several atmospheric optical phenomena, with a general definition as a broad arch of whitish or pinkish sunlight in the twilight sky, consisting of the bright segment and the purple light. Purple light mainly occurs when the Sun is 2--6° below the horizon, from civil to nautical twilight, while the bright segment lasts until the end of the nautical twilight. Afterglow is often in cases of volcanic eruptions discussed, while its purple light is discussed as a different particular volcanic purple light. Specifically in volcanic occurrences it is light scattered by fine particulates, like dust, suspended in the atmosphere. In the case of alpenglow, which is similar to the Belt of Venus, afterglow is used in general for the golden-red glowing light from the sunset and sunrise reflected in the sky, and in particularly for its last stage, when the purple light is reflected. The opposite of an afterglow is a foreglow, which occurs before sunrise. Sunlight reaches Earth around civil twilight during golden hour intensely in its low-energy and low-frequency red component. During this part of civil twilight after sunset and before sundawn the red sunlight remains visible by scattering through particles in the air. Backscattering, possibly after being reflected off clouds or high snowfields in mountain regions, furthermore creates a reddish to pinkish light. The high-energy and high-frequency components of light towards blue are scattered out broadly, producing the broader blue light of nautical twilight before or after the reddish light of civil twilight, while in combination with the reddish light producing the purple light. This period of blue dominating is referred to as the blue hour and is, like the golden hour, widely treasured by photographers and painters. After the 1883 eruption of the volcano Krakatoa, a remarkable series of red sunsets appeared worldwide. An enormous amount of exceedingly fine dust were blown to a great height by the volcano\'s explosion, and then globally diffused by the high atmospheric winds. Edvard Munch\'s painting The Scream possibly depicts an afterglow during this period. <File:Dämmerung> mit Purpurlicht und Schattenstrahlen, 10.10.2011 bei Limburg VIII.jpg\\|Purple light with crepuscular shadow <File:Lamma> evening4.jpg\\|Sunset in Hong Kong after the 1991 eruption of Mount Pinatubo <File:Dresden.afterglow.700px.jpg%7CAn> afterglow in Dresden, Saxony, Germany <File:Afterglow.jpg%7CAn> afterglow in Slovenian mountains, near Triglav Lakes Valley <File:Full> Image Sunset Bates College Lewiston Maine July 3 2008 8.30PM.JPG\\|Sunset over the Bates College track in Lewiston, Maine <File:Noarlunga> Pier, Adelaide.jpg\\|An afterglow at a pier in Australia <File:Afterglow> in Sanchong, New Taipei 20140114.jpg\\|An afterglow on skyscrapers in New Taipei, Taiwan <File:Afterglow> Kraków.JPG\\|An afterglow on a Kraków housing estate <File:Optical> effect march sunset - NOAA.jpg\\|Additional to foreglow here refracted sunlight reaches the South Pole just before actual sunrise. At Earth\'s poles the Sun appears at the horizon only and all day around equinox, marking the change between the half year long polar night and polar day.	2025-06-20T00:00:00
3,130	Advanced Power Management	Advanced power management (APM) is a technical standard for power management developed by Intel and Microsoft and released in 1992 which enables an operating system running an IBM-compatible personal computer to work with the BIOS (part of the computer\'s firmware) to achieve power management. Revision 1.2 was the last version of the APM specification, released in 1996. ACPI is the successor to APM. Microsoft dropped support for APM in Windows Vista. The Linux kernel still mostly supports APM, though support for APM CPU idle was dropped in version 3.0. ## Overview APM uses a layered approach to manage devices. APM-aware applications (which include device drivers) talk to an OS-specific APM driver. This driver communicates to the APM-aware BIOS, which controls the hardware. There is the ability to opt out of APM control on a device-by-device basis, which can be used if a driver wants to communicate directly with a hardware device. Communication occurs both ways; power management events are sent from the BIOS to the APM driver, and the APM driver sends information and requests to the BIOS via function calls. In this way the APM driver is an intermediary between the BIOS and the operating system. Power management happens in two ways; through the above-mentioned function calls from the APM driver to the BIOS requesting power state changes, and automatically based on device activity. In APM 1.0 and APM 1.1, power management is almost fully controlled by the BIOS. In APM 1.2, the operating system can control PM time (e.g. suspend timeout). In 1997, Phoenix Technologies released \"APM 2.0\" which is a kernel device driver compatible with an APM 1.2 BIOS. ## Power management events {#power_management_events} There are 12 power events (such as standby, suspend and resume requests, and low battery notifications), plus OEM-defined events, that can be sent from the APM BIOS to the operating system. The APM driver regularly polls for event change notifications. Power Management Events: Name Code Comment ------------------------------------------ -------- ------------------------------------------ System Standby Request Notification 0x0001 System Suspend Request Notification 0x0002 Normal Resume System Notification 0x0003 Critical Resume System Notification 0x0004 Battery Low Notification 0x0005 Power Status Change Notification 0x0006 Update Time Notification 0x0007 Critical System Suspend Notification 0x0008 User System Standby Request Notification 0x0009 User System Suspend Request Notification 0x000A System Standby Resume Notification 0x000B Capabilities Change Notification 0x000C Due to setup or device insertion/removal ## APM functions {#apm_functions} There are 21 APM function calls defined that the APM driver can use to query power management statuses, or request power state transitions. Example function calls include letting the BIOS know about current CPU usage (the BIOS may respond to such a call by placing the CPU in a low-power state, or returning it to its full-power state), retrieving the current power state of a device, or requesting a power state change. +---------------------------------------------+------+--------------------------------------------------------------+ \| Name \| Code \| Comment \| +=============================================+======+==============================================================+ \| APM Installation Check \| 0x00 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| APM Real Mode Interface Connect \| 0x01 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| APM Protected Mode 16-bit Interface Connect \| 0x02 \| Avoids real or virtual86 mode. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| APM Protected Mode 32-bit Interface Connect \| 0x03 \| Avoids real or virtual86 mode. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| APM Interface Disconnect \| 0x04 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| CPU Idle \| 0x05 \| Requests system suspend.\ \| \| \| \| 0) Clock halted until timer tick interrupt.\ \| \| \| \| 1) Slow clock \| +---------------------------------------------+------+--------------------------------------------------------------+ \| CPU Busy \| 0x06 \| Driver tells system APM to restore clock speed of the CPU. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Set Power State \| 0x07 \| Set system or device into Suspend/Standby/Off state. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Enable/Disable Power Management \| 0x08 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Restore APM BIOS Power-On Defaults \| 0x09 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Get Power Status \| 0x0A \| Supports AC status \"On backup power\". And battery status. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Get PM Event \| 0x0B \| Checks for APM events. Shall be called once per second. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Get Power State \| 0x0C \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Enable/Disable Device Power Management \| 0x0D \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| APM Driver Version \| 0x0E \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Engage/Disengage Power Management \| 0x0F \| APM management for a specific device. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Get Capabilities \| 0x10 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Get/Set/Disable Resume Timer \| 0x11 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Enable/Disable Resume on Ring Indicator \| 0x12 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| Enable/Disable Timer Based Requests \| 0x13 \| \| +---------------------------------------------+------+--------------------------------------------------------------+ \| OEM APM Installation Check \| 0x80 \| Tells if APM BIOS supports OEM hardware dependent functions. \| +---------------------------------------------+------+--------------------------------------------------------------+ \| OEM APM Function \| 0x80 \| Access to OEM specific functions. \| +---------------------------------------------+------+--------------------------------------------------------------+ ## Power states {#power_states} The APM specification defines system power states and device power states. ### System power states {#system_power_states} APM defines five power states for the computer system: - Full On: The computer is powered on, and no devices are in a power saving mode. - APM Enabled: The computer is powered on, and APM is controlling device power management as needed. - APM Standby: Most devices are in their low-power state, the CPU is slowed or stopped, and the system state is saved. The computer can be returned to its former state quickly (in response to activity such as the user pressing a key on the keyboard). - APM Suspend: Most devices are powered off, but the system state is saved. The computer can be returned to its former state, but takes a relatively long time. (Hibernation is a special form of the APM Suspend state). - Off: The computer is turned off. ### Device power states {#device_power_states} APM also defines power states that APM-aware hardware can implement. There is no requirement that an APM-aware device implement all states. The four states are: - Device On: The device is in full power mode. - Device Power Managed: The device is still powered on, but some functions may not be available, or may have reduced performance. - Device Low Power: The device is not working. Power is maintained so that the device may be \'woken up\'. - Device Off: The device is powered off. ## Hardware components {#hardware_components} ### CPU The CPU core (defined in APM as the CPU clock, cache, system bus and system timers) is treated specially in APM, as it is the last device to be powered down, and the first device to be powered back up. The CPU core is always controlled through the APM BIOS (there is no option to control it through a driver). Drivers can use APM function calls to notify the BIOS about CPU usage, but it is up to the BIOS to act on this information; a driver cannot directly tell the CPU to go into a power saving state. ### ATA drives {#ata_drives} The ATA specification and SATA specification defines APM provisions for hard drives, which specifies a trade-off between spin-down frequency and always-on performance. Unlike the BIOS-side APM, the ATA APM and SATA APM has never been deprecated. Aggressive spin-down frequencies may reduce drive lifespan by unnecessarily accumulating load cycles; most modern drives are specified to sustain 300,000 cycles and usually last at least 600,000. On the other hand, not spinning down the drive will cause extra power draw and heat generation; high temperatures also reduce the lifespan of hard drives.	2025-06-20T00:00:00
3,132	Adolphe Sax	Antoine-Joseph \"Adolphe\" Sax (`{{IPA\|fr\|ɑ̃twan ʒozɛf adɔlf saks\|lang}}`{=mediawiki}; 6 November 1814 -- 7 February 1894) was a Belgian inventor and musician who invented the saxophone in the early 1840s, patenting it in 1846. He also invented the saxotromba, saxhorn and saxtuba, and redesigned the bass clarinet in a fashion still used in the 21st century. He played the flute and clarinet. ## Early life {#early_life} Antoine-Joseph Sax was born on 6 November 1814 in Dinant, in what is now Belgium, to Charles-Joseph Sax and his wife Marie-Joseph (Masson). While his given name was Antoine-Joseph, he was referred to as Adolphe from childhood. His father and mother were instrument designers themselves, who made several changes to the design of the French horn. Adolphe began to make his own instruments at an early age, entering two of his flutes and a clarinet into a competition at the age of 15. He subsequently studied performance on those two instruments as well as voice at the Royal Conservatory of Brussels. Sax faced many brushes with death. As a child, he once fell from a height of three floors, hit his head on a stone and was believed dead. At the age of three, he drank a bowl full of acidic water, mistaking it for milk, and later swallowed a pin. He received serious burns from a gunpowder explosion and once fell onto a hot cast-iron frying pan, burning his side. Several times he avoided accidental poisoning and asphyxiation from sleeping in a room where varnished furniture was drying. Another time young Sax was struck on the head by a cobblestone and fell into a river, almost dying. His mother once said that \"he\'s a child condemned to misfortune; he won\'t live\". His neighbors called him \"little Sax, the ghost\". ## Career and later life {#career_and_later_life} After leaving the Royal Conservatory of Brussels, Sax began to experiment with new instrument designs, while his parents continued their business of making conventional instruments. Sax\'s first important invention was an improvement in bass clarinet design, which he patented at the age of 24. He relocated permanently to Paris in 1842 and began working on a new set of valved bugles. While he did not invent this instrument, his examples were much more successful than those of his rivals and became known as saxhorns. Hector Berlioz was so enamoured of these that he arranged in February 1844 for one of his pieces to be played entirely on saxhorns. They were made in seven different sizes and paved the way for the creation of the flugelhorn. Today saxhorns are sometimes used in concert bands, marching bands, and orchestras. The saxhorn also laid the groundwork for the modern euphonium. Sax also developed the saxotromba family, valved brass instruments with narrower bore than the saxhorns, in 1845, though they survived only briefly. The use of saxhorns spread rapidly. The saxhorn valves were accepted as state-of-the-art in their time and remain largely unchanged today. The advances made by Adolphe Sax were soon followed by the British brass band movement, which exclusively adopted the saxhorn family of instruments. A decade after saxhorns became available, the Jedforest Instrumental Band (1854) and The Hawick Saxhorn Band (1855) were formed in the Scottish Borders. The period around 1840 saw Sax inventing the clarinette-bourdon, an early unsuccessful design of contrabass clarinet. On 28 June 1846 he patented the saxophone, intended for use in orchestras and military bands. By 1846 Sax had designed saxophones ranging from sopranino to subcontrabass, although not all were built. Composer Hector Berlioz wrote approvingly of the new instrument in 1842, but despite his support, saxophones did not become a standard part of the orchestra. Their ability to play technical passages easily like woodwinds yet project loudly like brass instruments led to their inclusion in military bands in France and elsewhere. During the Crimean War (1853--1856), Sax made two more inventions, though neither was ever actually built: First, he designed the \"Saxotonnerre\", a massive, locomotive-powered organ which was supposed to be so loud as to be heard across all of Paris at once. The second was developed in response to the Crimean War\'s Siege of Sevastopol where the French military and its allies were locked in a destructive conflict. As a potential solution to such lengthy sieges, Sax thus designed the \"Saxocannon\", a giant cannon whose half-ton round shots would be powerful enough to completely destroy an \"average-sized city\". Sax\'s reputation eventually helped secure him a job teaching at the Paris Conservatory in 1857. He continued to make instruments later in life and presided over the new saxophone course at the Paris Conservatory. Legal troubles involving patents continued for over 20 years, with rival instrument makers attacking the legitimacy of his patents and Sax suing them for patent infringement. He was driven into bankruptcy three times: in 1852, 1873 and 1877. Sax suffered from lip cancer between 1853 and 1858 but made a full recovery. In 1894 he died of pneumonia in Paris, in poverty, and was interred in section 5 (Avenue de Montebello) at the Cimetière de Montmartre in Paris. <File:Saxtromba> sopran.jpg\\|Saxotromba <File:MHS> Saxhorn.jpg\\|Saxhorn <File:Saxtuba1867.jpg>\\|Saxtuba <File:Trombone> a six pistons-IMG 0853-black.jpg\\|6-piston trombone <File:Bass> saxhorn, 1863.jpg\\|A bass saxhorn, 1863 ## Honors and awards {#honors_and_awards} In his birthplace Dinant in Belgium, Mr Sax\'s House is dedicated to his life and saxophones. - 1849: Awarded the Chevalier rank of the Legion of Honour. - 1867: 1\<sup\>e\</sup\> Grand Prix de la Facture Instrumentale at the 1867 Paris International Exposition. - 1995: In 1995, his likeness was featured on the front of Belgium\'s 200 Belgian francs banknote. - 2015: Google Doodle commemorated his 201st birthday.	2025-06-20T00:00:00
3,134	Aspirated consonant	In phonetics, aspiration is a strong burst of breath that accompanies either the release or, in the case of preaspiration, the closure of some obstruents. In English, aspirated consonants are allophones in complementary distribution with their unaspirated counterparts, but in some other languages, notably most South Asian languages and East Asian languages, the difference is contrastive. ## Transcription In the International Phonetic Alphabet (IPA), aspirated consonants are written using the symbols for voiceless consonants followed by the aspiration modifier letter `{{angbr IPA\|◌ʰ}}`{=mediawiki}, a superscript form of the symbol for the voiceless glottal fricative `{{angbr IPA\|h}}`{=mediawiki}. For instance, `{{angbr IPA\|p}}`{=mediawiki} represents the voiceless bilabial stop, and `{{angbr IPA\|pʰ}}`{=mediawiki} represents the aspirated bilabial stop. Voiced consonants are seldom actually aspirated. Symbols for voiced consonants followed by `{{angbr IPA\|◌ʰ}}`{=mediawiki}, such as `{{angbr IPA\|bʰ}}`{=mediawiki}, typically represent consonants with murmured voiced release (see below). In the grammatical tradition of Sanskrit, aspirated consonants are called voiceless aspirated, and breathy-voiced consonants are called voiced aspirated. There are no dedicated IPA symbols for degrees of aspiration and typically only two degrees are marked: unaspirated `{{angbr IPA\|k}}`{=mediawiki} and aspirated `{{angbr IPA\|kʰ}}`{=mediawiki}. An old symbol for light aspiration was `{{angbr IPA\|ʻ}}`{=mediawiki}, but this is now obsolete. The aspiration modifier letter may be doubled to indicate especially strong or long aspiration. Hence, the two degrees of aspiration in Korean stops are sometimes transcribed `{{angbr IPA\|kʰ kʰʰ}}`{=mediawiki} or `{{angbr IPA\|kʻ}}`{=mediawiki} and `{{angbr IPA\|kʰ}}`{=mediawiki}, but they are usually transcribed `{{IPA\|[k]}}`{=mediawiki} and `{{IPA\|[kʰ]}}`{=mediawiki}, with the details of voice onset time given numerically. Preaspirated consonants are marked by placing the aspiration modifier letter before the consonant symbol: `{{angbr IPA\|ʰp}}`{=mediawiki} represents the preaspirated bilabial stop. Unaspirated or tenuis consonants are occasionally marked with the modifier letter for unaspiration `{{angbr IPA\|◌˭}}`{=mediawiki}, a superscript equals sign: `{{angbr IPA\|t˭}}`{=mediawiki}. Usually, however, unaspirated consonants are left unmarked: `{{angbr IPA\|t}}`{=mediawiki}. ## Phonetics Voiceless consonants are produced with the vocal folds open (spread) and not vibrating, and voiced consonants are produced when the vocal folds are fractionally closed and vibrating (modal voice). Voiceless aspiration occurs when the vocal folds remain open after a consonant is released. An easy way to measure this is by noting the consonant\'s voice onset time, as the voicing of a following vowel cannot begin until the vocal folds close. In some languages, such as Navajo, aspiration of stops tends to be phonetically realised as voiceless velar airflow; aspiration of affricates is realised as an extended length of the frication. Aspirated consonants are not always followed by vowels or other voiced sounds. For example, in Eastern Armenian, aspiration is contrastive even word-finally, and aspirated consonants occur in consonant clusters. In Wahgi, consonants are aspirated only when they are in final position. ### Degree The degree of aspiration varies: the voice onset time of aspirated stops is longer or shorter depending on the language or the place of articulation. Armenian and Cantonese have aspiration that lasts about as long as English aspirated stops, in addition to unaspirated stops. Korean has lightly aspirated stops that fall between the Armenian and Cantonese unaspirated and aspirated stops as well as strongly-aspirated stops whose aspiration lasts longer than that of Armenian or Cantonese. (See voice onset time.) Aspiration varies with place of articulation. The Spanish voiceless stops `{{IPA\|/p t k/}}`{=mediawiki} have voice onset times (VOTs) of about 5, 10, and 30 milliseconds, and English aspirated `{{IPA\|/p t k/}}`{=mediawiki} have VOTs of about 60, 70, and 80 ms. Voice onset time in Korean has been measured at 20, 25, and 50 ms for `{{IPA\|/p t k/}}`{=mediawiki} and 90, 95, and 125 for `{{IPA\|/pʰ tʰ kʰ/}}`{=mediawiki}. ### Doubling When aspirated consonants are doubled or geminated, the stop is held longer and then has an aspirated release. An aspirated affricate consists of a stop, fricative, and aspirated release. A doubled aspirated affricate has a longer hold in the stop portion and then has a release consisting of the fricative and aspiration. ### Preaspiration Icelandic and Faroese have consonants with preaspiration `{{IPA\|[ʰp ʰt ʰk]}}`{=mediawiki}, and some scholars`{{who\|date=April 2017}}`{=mediawiki} interpret them as consonant clusters as well. In Icelandic, preaspirated stops contrast with double stops and single stops: Word IPA Meaning ---------- ---------------------------------- --------- kapp or `{{IPA\|[kʰɑhp]}}`{=mediawiki} zeal gabb hoax gap opening Preaspiration is also a feature of Scottish Gaelic: Word IPA Meaning --------- ----- --------- cat cat Preaspirated stops also occur in most Sami languages. For example, in Northern Sami, the unvoiced stop and affricate phonemes `{{IPA\|/p/}}`{=mediawiki}, `{{IPA\|/t/}}`{=mediawiki}, `{{IPA\|/ts/}}`{=mediawiki}, `{{IPA\|/tʃ/}}`{=mediawiki}, `{{IPA\|/k/}}`{=mediawiki} are pronounced preaspirated (`{{IPA\|[ʰp]}}`{=mediawiki}, `{{IPA\|[ʰt]}}`{=mediawiki} `{{IPA\|[ʰts]}}`{=mediawiki}, `{{IPA\|[ʰtʃ]}}`{=mediawiki}, `{{IPA\|[ʰk]}}`{=mediawiki}) in medial or final position. ### Fricatives and sonorants {#fricatives_and_sonorants} Although most aspirated obstruents in the world\'s languages are stops and affricates, aspirated fricatives such as `{{IPA\|[sʰ]}}`{=mediawiki}, `{{IPA\|[ɸʷʰ]}}`{=mediawiki} and `{{IPA\|[ɕʰ]}}`{=mediawiki} have been documented in Korean and Xuanzhou Wu, and `{{IPA\|[xʰ]}}`{=mediawiki} has been described for Spanish, though these are allophones of other phonemes. Similarly, aspirated fricatives and even aspirated nasals, approximants, and trills occur in a few Tibeto-Burman languages, some Oto-Manguean languages, the Hmongic language Hmu, the Siouan language Ofo, and the Chumashan languages Barbareño and Ventureño. Some languages, such as Choni Tibetan, have as many as four contrastive aspirated fricatives `{{IPA\|[sʰ]}}`{=mediawiki} `{{IPA\|[ɕʰ]}}`{=mediawiki}, `{{IPA\|[ʂʰ]}}`{=mediawiki} and `{{IPA\|[xʰ]}}`{=mediawiki}. ### `{{anchor\|Voiced stop}}`{=mediawiki}Voiced consonants with voiceless aspiration {#voiced_consonants_with_voiceless_aspiration} True aspirated voiced consonants, as opposed to murmured (breathy-voice) consonants such as the `{{IPA\|[bʱ], [dʱ], [ɡʱ]}}`{=mediawiki} that are common among the languages of India, are extremely rare. They have been documented in Kelabit. ## Phonology Aspiration has varying significance in different languages. It is either allophonic or phonemic, and may be analyzed as an underlying consonant cluster. ### Allophonic In some languages, stops are distinguished primarily by voicing, and voiceless stops are sometimes aspirated, while voiced stops are usually unaspirated. English voiceless stops are aspirated for most native speakers when they are word-initial or begin a stressed syllable. Pronouncing them as unaspirated in these positions, as is done by many Indian English speakers, may make them get confused with the corresponding voiced stop by other English-speakers. Conversely, this confusion does not happen with the native speakers of languages which have aspirated and unaspirated but not voiced stops, such as Mandarin Chinese. S+consonant clusters can vary between aspirated and unaspirated forms depending on whether the cluster crosses a morpheme boundary. For example, distend features an unaspirated \[t\] because it is not analyzed as comprising two morphemes. In contrast, distaste includes an aspirated middle \[tʰ\] since it is analyzed as dis- + taste, and the word taste begins with an aspirated \[t\]. Word-final voiceless stops are sometimes aspirated. Voiceless stops in Pashto are slightly aspirated prevocalically in a stressed syllable. ### Phonemic In many languages, such as Hindi, tenuis and aspirated consonants are phonemic. Unaspirated consonants like `{{IPA\|[p˭ s˭]}}`{=mediawiki} and aspirated consonants like `{{IPA\|[pʰ ʰp sʰ]}}`{=mediawiki} are separate phonemes, and words are distinguished by whether they have one or the other. #### Consonant cluster {#consonant_cluster} Alemannic German dialects have unaspirated `{{IPA\|[p˭ t˭ k˭]}}`{=mediawiki} as well as aspirated `{{IPA\|[pʰ tʰ kʰ]}}`{=mediawiki}; the latter series are usually viewed as consonant clusters. ### Absence French, Standard Dutch, Afrikaans, Tamil, Finnish, Portuguese, Italian, Spanish, Russian, Polish, Latvian and Modern Greek are languages that do not have phonetic aspirated consonants. ## Examples ### Chinese Standard Chinese (Mandarin) has stops and affricates distinguished by aspiration: for instance, `{{IPA\|/t tʰ/}}`{=mediawiki}, `{{IPA\|/t͡s t͡sʰ/}}`{=mediawiki}. In pinyin, tenuis stops are written with letters that represent voiced consonants in English, and aspirated stops with letters that represent voiceless consonants. Thus d represents `{{IPA\|/t/}}`{=mediawiki}, and t represents `{{IPA\|/tʰ/}}`{=mediawiki}. Wu Chinese and Southern Min has a three-way distinction in stops and affricates: `{{IPA\|/p pʰ b/}}`{=mediawiki}. In addition to aspirated and unaspirated consonants, there is a series of muddy consonants, like `{{IPA\|/b/}}`{=mediawiki}. These are pronounced with slack or breathy voice: that is, they are weakly voiced. Muddy consonants as initial cause a syllable to be pronounced with low pitch or light (陽 yáng) tone. ### Indian languages {#indian_languages} Many Indo-Aryan languages have aspirated stops. Sanskrit, Hindustani, Bengali, Marathi, and Gujarati have a four-way distinction in stops: voiceless, aspirated, voiced, and voiced aspirated, such as `{{IPA\|/p pʰ b bʱ/}}`{=mediawiki}. Punjabi has lost voiced aspirated consonants, which resulted in a tone system, and therefore has a distinction between voiceless, aspirated, and voiced: `{{IPA\|/p pʰ b/}}`{=mediawiki}. Other languages such as Telugu, Malayalam, and Kannada, have a distinction between voiced and voiceless, aspirated and unaspirated. However, in all of these languages, aspirated consonant occur (mostly) in borrowed words, and commonly substituted with their unaspirated counterparts. ### Armenian Most dialects of Armenian have aspirated stops, and some have breathy-voiced stops. Classical and Eastern Armenian have a three-way distinction between voiceless, aspirated, and voiced, such as `{{IPA\|/t tʰ d/}}`{=mediawiki}. Western Armenian has a two-way distinction between aspirated and voiced: `{{IPA\|/tʰ d/}}`{=mediawiki}. Western Armenian aspirated `{{IPA\|/tʰ/}}`{=mediawiki} corresponds to Eastern Armenian aspirated `{{IPA\|/tʰ/}}`{=mediawiki} and voiced `{{IPA\|/d/}}`{=mediawiki}, and Western voiced `{{IPA\|/d/}}`{=mediawiki} corresponds to Eastern voiceless `{{IPA\|/t/}}`{=mediawiki}. ### Greek Ancient Greek, including the Classical Attic and Koine Greek dialects, had a three-way distinction in stops like Eastern Armenian: `{{IPA\|/t tʰ d/}}`{=mediawiki}. These series were called `{{wikt-lang\|grc\|ψιλός\|ψιλά}}`{=mediawiki}, `{{wikt-lang\|grc\|δασύς\|δασέα}}`{=mediawiki}, `{{wikt-lang\|grc\|μέσος\|μέσα}}`{=mediawiki} (psilá, daséa, mésa) \"smooth, rough, intermediate\", respectively, by Koine Greek grammarians. There were aspirated stops at three places of articulation: labial, coronal, and velar `{{IPA\|/pʰ tʰ kʰ/}}`{=mediawiki}. Earlier Greek, represented by Mycenaean Greek, likely had a labialized velar aspirated stop `{{IPA\|/kʷʰ/}}`{=mediawiki}, which later became labial, coronal, or velar depending on dialect and phonetic environment. The other Ancient Greek dialects, Ionic, Doric, Aeolic, and Arcadocypriot, likely had the same three-way distinction at one point, but Doric seems to have had a fricative in place of `{{IPA\|/tʰ/}}`{=mediawiki} in the Classical period. Later, during the Koine and Medieval Greek periods, the aspirated and voiced stops `{{IPA\|/tʰ d/}}`{=mediawiki} of Attic Greek lenited to voiceless and voiced fricatives, yielding `{{IPA\|/θ ð/}}`{=mediawiki} in Medieval and Modern Greek. Cypriot Greek is notable for aspirating its inherited (and developed across word-boundaries) voiceless geminate stops, yielding the series /pʰː tʰː cʰː kʰː/. ## Other uses {#other_uses} ### Debuccalization The term aspiration sometimes refers to the sound change of debuccalization, in which a consonant is lenited (weakened) to become a glottal stop or fricative `{{IPA\|[ʔ h ɦ]}}`{=mediawiki}. ### Breathy-voiced release {#breathy_voiced_release} So-called voiced aspirated consonants are nearly always pronounced instead with breathy voice, a type of phonation or vibration of the vocal folds. The modifier letter `{{angbr IPA\|◌ʰ}}`{=mediawiki} after a voiced consonant actually represents a breathy-voiced or murmured consonant, as with the \"voiced aspirated\" bilabial stop `{{angbr IPA\|bʰ}}`{=mediawiki} in the Indo-Aryan languages. This consonant is therefore more accurately transcribed as `{{angbr IPA\|b̤}}`{=mediawiki}, with the diacritic for breathy voice, or with the modifier letter `{{angbr IPA\|bʱ}}`{=mediawiki}, a superscript form of the symbol for the voiced glottal fricative `{{angbr IPA\|ɦ}}`{=mediawiki}. Some linguists restrict the double-dot subscript `{{angbr IPA\|◌̤}}`{=mediawiki} to murmured sonorants, such as vowels and nasals, which are murmured throughout their duration, and use the superscript hook-aitch `{{angbr IPA\|◌ʱ}}`{=mediawiki} for the breathy-voiced release of obstruents.	2025-06-20T00:00:00
3,160	Alternative algebra	In abstract algebra, an alternative algebra is an algebra in which multiplication need not be associative, only alternative. That is, one must have - $x(xy) = (xx)y$ - $(yx)x = y(xx)$ for all x and y in the algebra. Every associative algebra is obviously alternative, but so too are some strictly non-associative algebras such as the octonions. ## The associator {#the_associator} Alternative algebras are so named because they are the algebras for which the associator is alternating. The associator is a trilinear map given by $$[x,y,z] = (xy)z - x(yz)$$. By definition, a multilinear map is alternating if it vanishes whenever two of its arguments are equal. The left and right alternative identities for an algebra are equivalent to $$[x,x,y] = 0$$ $$[y,x,x] = 0$$ Both of these identities together imply that: $$[x,y,x]=[x,x,x]+[x,y,x]+$$ $$-[x,x+y,x+y] =$$ $$= [x,x+y,-y] =$$ $$= [x,x,-y] - [x,y,y] = 0$$ for all $x$ and $y$. This is equivalent to the flexible identity $$(xy)x = x(yx).$$ The associator of an alternative algebra is therefore alternating. Conversely, any algebra whose associator is alternating is clearly alternative. By symmetry, any algebra which satisfies any two of: - left alternative identity: $x(xy) = (xx)y$ - right alternative identity: $(yx)x = y(xx)$ - flexible identity: $(xy)x = x(yx).$ is alternative and therefore satisfies all three identities. An alternating associator is always totally skew-symmetric. That is, $$[x_{\sigma(1)}, x_{\sigma(2)}, x_{\sigma(3)}] = \sgn(\sigma)[x_1,x_2,x_3]$$ for any permutation $\sigma$. The converse holds so long as the characteristic of the base field is not 2. ## Examples - Every associative algebra is alternative. - The octonions form a non-associative alternative algebra, a normed division algebra of dimension 8 over the real numbers. - More generally, any octonion algebra is alternative. ### Non-examples {#non_examples} - The sedenions, trigintaduonions, and all higher Cayley--Dickson algebras lose alternativity. ## Properties Artin\'s theorem states that in an alternative algebra the subalgebra generated by any two elements is associative. Conversely, any algebra for which this is true is clearly alternative. It follows that expressions involving only two variables can be written unambiguously without parentheses in an alternative algebra. A generalization of Artin\'s theorem states that whenever three elements $x,y,z$ in an alternative algebra associate (i.e., $[x,y,z] = 0$), the subalgebra generated by those elements is associative. A corollary of Artin\'s theorem is that alternative algebras are power-associative, that is, the subalgebra generated by a single element is associative. The converse need not hold: the sedenions are power-associative but not alternative. The Moufang identities - $a(x(ay)) = (axa)y$ - $((xa)y)a = x(aya)$ - $(ax)(ya) = a(xy)a$ hold in any alternative algebra. In a unital alternative algebra, multiplicative inverses are unique whenever they exist. Moreover, for any invertible element $x$ and all $y$ one has $$y = x^{-1}(xy).$$ This is equivalent to saying the associator $[x^{-1},x,y]$ vanishes for all such $x$ and $y$. If $x$ and $y$ are invertible then $xy$ is also invertible with inverse $(xy)^{-1} = y^{-1}x^{-1}$. The set of all invertible elements is therefore closed under multiplication and forms a Moufang loop. This loop of units in an alternative ring or algebra is analogous to the group of units in an associative ring or algebra. Kleinfeld\'s theorem states that any simple non-associative alternative ring is a generalized octonion algebra over its center. The structure theory of alternative rings is presented in the book Rings That Are Nearly Associative by Zhevlakov, Slin\'ko, Shestakov, and Shirshov. ## Occurrence The projective plane over any alternative division ring is a Moufang plane. Every composition algebra is an alternative algebra, as shown by Guy Roos in 2008: A composition algebra A over a field K has a norm n that is a multiplicative homomorphism: $n(a \times b) = n(a) \times n(b)$ connecting (A, ×) and (K, ×). Define the form ( \_ : \_ ): A × A → K by $(a:b) = n(a+b) - n(a) - n(b).$ Then the trace of a is given by (a:1) and the conjugate by a\* = (a:1)e -- a where e is the basis element for 1. A series of exercises prove that a composition algebra is always an alternative algebra.	2025-06-20T00:00:00
3,168	Afrobeat	Afrobeat (also known as Afrofunk) is a West African music genre, fusing influences from Nigerian (such as Yoruba) and Ghanaian (such as highlife) music, with American funk, jazz, and soul influences. With a focus on chanted vocals, complex intersecting rhythms, and percussion, the style was pioneered in the 1960s by Nigerian multi-instrumentalist and bandleader Fela Kuti, who popularised it both within and outside Nigeria. At the height of his popularity, he was referred to as one of Africa\'s most \"challenging and charismatic music performers.\" Distinct from Afrobeat is Afrobeats, a combination of sounds originating in West Africa in the 21st century. This takes on diverse influences and is an eclectic combination of genres such as hip hop, house, jùjú, ndombolo, R&B, soca, and dancehall. The two genres, though often conflated, are not the same. ## History Afrobeat evolved in Nigeria in the late 1960s by Fela Anikulapo Kuti, (born Olufela Olusegun Oludotun) who, with drummer Tony Allen, experimented with different contemporary music of that time. Afrobeat was influenced by a combination of different genres, such as highlife, fuji, and jùjú, as well as Yoruba vocal traditions, rhythm, and instruments. In the late 1950s, Kuti left Lagos to study abroad at the London School of Music, where he took lessons in piano and percussion and was exposed to jazz. Fela Kuti returned to Lagos and played a highlife-jazz hybrid, albeit, without commercial success. In 1969, Kuti and his band went on a trip to the U.S. and met a woman by the name of Sandra Smith, a singer and former Black Panther. Sandra Smith (now known as Sandra Izsadore or Sandra Akanke Isidore) introduced Kuti to many writings of activists such as Martin Luther King Jr., Angela Davis, Jesse Jackson, and his biggest influence of all, Malcolm X. As Kuti was interested in African-American politics, Smith would make it her duty to inform Kuti of current events; in return, Kuti would fill her in on African culture. Since Kuti stayed at Smith\'s house and spent so much time with her, he started to re-evaluate his music genre. That was when Kuti realized that he was not playing African music. From that day forward, Kuti changed his sound and the message behind his music. Upon arriving in Nigeria, Kuti had also changed the name of his group to \"Africa \'70\". The new sound hailed from a club he established called the Afrika Shrine. The band maintained a five-year residency at the Afrika Shrine from 1970 to 1975 while Afrobeat thrived among Nigerian youth. Another influential person Ray Stephen Oche, a Nigerian musician touring from Paris, France, with his Matumbo orchestra in the 1970s. The name was partially born out of an attempt to distinguish Fela Kuti\'s music from the soul music of American artists such as James Brown. Prevalent in his and Lagbaja\'s music are native Nigerian harmonies and rhythms, taking contrasting elements and combining, modernizing, and improvising upon them. Politics is essential to Afrobeat because Kuti uses social criticism to pave the way for change. His message can be described as confrontational and controversial, which relates to the political climate of most African countries in the 1970s, many of which were dealing with political injustice and military corruption while recovering from the transition from colonial governments to self-determination. Many bands took up the style as the genre spread throughout the African continent. The recordings of these bands and their songs were rarely heard or exported outside the originating countries, but many can now be found on compilation albums and CDs from specialist record shops. ## Influence Many jazz musicians have been attracted to the aromatic genre of Afrobeat. From Roy Ayers in the 1970s to Randy Weston in the 1990s, there have been collaborations that resulted in albums such as Africa: Centre of the World by Roy Ayers, released on the Polydore label in 1981. In 1994, Branford Marsalis, the American jazz saxophonist, included samples of Fela\'s \"Beasts of No Nation\" on his Buckshot LeFonque album. Afrobeat has also profoundly influenced various `{{According to whom\|important\|date=March 2023}}`{=mediawiki} contemporary producers and musicians, such as Brian Eno and David Byrne, who credit Fela Kuti as an essential influence. Both worked on Talking Heads\' highly acclaimed 1980 album Remain in Light, which brought polyrhythmic Afrobeat influences to Western music. The new generation of DJs and musicians of the 2000s who have fallen in love with both Kuti\'s material and other rare releases have made compilations and remixes of these recordings, thus re-introducing the genre to new generations of listeners and fans of afropop and groove. In the late 1990s and early 2000s, a small Afrobeat scene began in Brooklyn, New York, with projects including Antibalas, The Daktaris and the Kokolo Afrobeat Orchestra. Since then, other artists like Zongo Junction have come onto the scene. Many others have cited Afrobeat as an influence, like Daptone Records-adjacent groups The Budos Band and El Michels Affair. The horn section of Antibalas have been guest musicians on TV on the Radio\'s highly acclaimed 2008 album Dear Science, as well as on British band Foals\' 2008 album Antidotes. Further examples are Val Veneto , Radio Bantu , Tam Tam Afrobeat , Combo Makabro , Marabunta Orquesta , Minga! , Antropofonica , Guanabana Afrobeat Orquesta , El Gran Capitan , Morbo y Mambo , Luka Afrobeat Orquesta or NikiLauda . Some Afrobeat influence can also be found in the music of Vampire Weekend and Paul Simon. In 2020, Antibalas was nominated for the Grammy Award for Best Global Music Album. Afrobeat artists of the 2000s and present continue to follow in the footsteps of Fela Kuti. Some examples of these artists are his sons Femi Kuti and Seun Kuti, Franck Biyong & Massak (from Cameroon), London Afrobeat Collective (from London, UK), Segun Damisa & the Afro-beat Crusaders, Shaolin Afronauts (from Adelaide, Australia), Newen Afrobeat (from Santiago, Chile), Lagos to Longbenton (based in Newcastle, UK), Eddy Taylor & the Heartphones (from Cologne, Germany), Bantucrew, the Albinoid Afrobeat Orchestra / Albinoid Sound System (from Strasbourg, France), Underground System / Underground System Afrobeat (from Brooklyn, New York), Abayomy Afrobeat Orquestra, Chicago Afrobeat Orchestra, Warsaw Afrobeat Orchestra, Karl Hector & the Malcouns (from Munich, Germany), Ojibo Afrobeat (from Vilnius, Lithuania), Afrodizz and Dele Sosimi and the ex-Africa \'70 members Oghene Kologbo (guitar) with Afrobeat Academy, Nicholas Addo-Nettey (percussion), who is also known as Pax Nicholas, with Ridimtaksi (both based in Berlin, Germany). Namibian artist EES (Eric Sell) associates Afrobeat with reggae and kwaito. In 2009, the music label Knitting Factory Records (KFR) produced the Broadway musical Fela! The story showcased Kuti\'s \"courage and incredible musical mastery\" along with the story of his life. The show had 11 Tony nominations, receiving three for Best Costumes, Best Sound and Best Choreography. Fela! was on Broadway for 15 months and was produced by notables such as Shawn \"Jay-Z \" Carter and Will and Jada Pinkett-Smith. Many celebrities were noted as attending the shows, including Denzel Washington, Madonna, Sting, Spike Lee (who saw it eight times), Kofi Annan, and Michelle Obama. Michelle Williams, former singer of girl group Destiny\'s Child, was cast as the role of Sandra Izsadore. Fela Kuti\'s music has been sampled by various hip-hop musicians such as Missy Elliott, J. Cole, and Kanye West, as well as other popular acts such as Beyoncé. The \"Festival de Afrobeat Independiente\" (FAI) takes place regularly in Buenos Aires, where regional bands as well as renown Afrobeat acts perform.	2025-06-20T00:00:00
3,170	Arithmetic function	In number theory, an arithmetic, arithmetical, or number-theoretic function is generally any function whose domain is the set of positive integers and whose range is a subset of the complex numbers. Hardy & Wright include in their definition the requirement that an arithmetical function \"expresses some arithmetical property of n\". There is a larger class of number-theoretic functions that do not fit this definition, for example, the prime-counting functions. This article provides links to functions of both classes. An example of an arithmetic function is the divisor function whose value at a positive integer n is equal to the number of divisors of n. Arithmetic functions are often extremely irregular (see table), but some of them have series expansions in terms of Ramanujan\'s sum. ## Multiplicative and additive functions {#multiplicative_and_additive_functions} An arithmetic function a is - completely additive if a(mn) = a(m) + a(n) for all natural numbers m and n; - completely multiplicative if a(1) = 1 and a(mn) = a(m)a(n) for all natural numbers m and n; Two whole numbers m and n are called coprime if their greatest common divisor is 1, that is, if there is no prime number that divides both of them. Then an arithmetic function a is - additive if a(mn) = a(m) + a(n) for all coprime natural numbers m and n; - multiplicative if a(1) = 1 and a(mn) = a(m)a(n) for all coprime natural numbers m and n. ## Notation In this article, $\sum_p f(p)$ and $\prod_p f(p)$ mean that the sum or product is over all prime numbers: $\sum_p f(p) = f(2) + f(3) + f(5) + \cdots$ and $\prod_p f(p)= f(2)f(3)f(5)\cdots.$ Similarly, $\sum_{p^k} f(p^k)$ and $\prod_{p^k} f(p^k)$ mean that the sum or product is over all prime powers with strictly positive exponent (so `{{math\|1=''k'' = 0}}`{=mediawiki} is not included): $\sum_{p^k} f(p^k) = \sum_p\sum_{k > 0} f(p^k) = f(2) + f(3) + f(4) +f(5) +f(7)+f(8)+f(9)+\cdots.$ The notations $\sum_{d\mid n} f(d)$ and $\prod_{d\mid n} f(d)$ mean that the sum or product is over all positive divisors of n, including 1 and n. For example, if `{{math\|1=''n'' = 12}}`{=mediawiki}, then $\prod_{d\mid 12} f(d) = f(1)f(2) f(3) f(4) f(6) f(12).$ The notations can be combined: $\sum_{p\mid n} f(p)$ and $\prod_{p\mid n} f(p)$ mean that the sum or product is over all prime divisors of n. For example, if n = 18, then $\sum_{p\mid 18} f(p) = f(2) + f(3),$ and similarly $\sum_{p^k\mid n} f(p^k)$ and $\prod_{p^k\mid n} f(p^k)$ mean that the sum or product is over all prime powers dividing n. For example, if n = 24, then $\prod_{p^k\mid 24} f(p^k) = f(2) f(3) f(4) f(8).$ ## Ω(n), ω(n), ν~p~(n) -- prime power decomposition {#ωn_ωn_νpn_prime_power_decomposition} The fundamental theorem of arithmetic states that any positive integer n can be represented uniquely as a product of powers of primes: $n = p_1^{a_1}\cdots p_k^{a_k}$ where p~1~ \< p~2~ \< \... \< p~k~ are primes and the a~j~ are positive integers. (1 is given by the empty product.) It is often convenient to write this as an infinite product over all the primes, where all but a finite number have a zero exponent. Define the p-adic valuation *ν~p~(n)* to be the exponent of the highest power of the prime p that divides n. That is, if p is one of the p~i~ then ν~p~(n) = a~i~, otherwise it is zero. Then $n = \prod_p p^{\nu_p(n)}.$ In terms of the above the prime omega functions ω and Ω are defined by `{{block indent \| em = 1.5 \| text = ''ω''(''n'') = ''k'',}}`{=mediawiki} `{{block indent \| em = 1.5 \| text = Ω(''n'') = ''a''<sub>1</sub> + ''a''<sub>2</sub> + ... + ''a''<sub>''k''</sub>.}}`{=mediawiki} To avoid repetition, formulas for the functions listed in this article are, whenever possible, given in terms of n and the corresponding p~i~, a~i~, ω, and Ω. ## Multiplicative functions {#multiplicative_functions} ### σ~k~(n), τ(n), d(n) -- divisor sums {#σkn_τn_dn_divisor_sums} *σ~k~(n)* is the sum of the kth powers of the positive divisors of n, including 1 and n, where k is a complex number. **σ~1~(n)*, the sum of the (positive) divisors of n, is usually denoted by *σ(n). Since a positive number to the zero power is one, σ~0~(n)** is therefore the number of (positive) divisors of n; it is usually denoted by **d(n) or τ(n)** (for the German Teiler = divisors). $\sigma_k(n) = \prod_{i=1}^{\omega(n)} \frac{p_i^{(a_i+1)k}-1}{p_i^k-1}= \prod_{i=1}^{\omega(n)} \left(1 + p_i^k + p_i^{2k} + \cdots + p_i^{a_i k}\right).$ Setting k = 0 in the second product gives $\tau(n) = d(n) = (1 + a_{1})(1+a_{2})\cdots(1+a_{\omega(n)}).$ ### φ(n) -- Euler totient function {#φn_euler_totient_function} **φ(n)*, the Euler totient function, is the number of positive integers not greater than n* that are coprime to n. $\varphi(n) = n \prod_{p\mid n} \left(1-\frac{1}{p}\right) = n \left(\frac{p_1 - 1}{p_1}\right)\left(\frac{p_2 - 1}{p_2}\right) \cdots \left(\frac{p_{\omega(n)} - 1}{p_{\omega(n)}}\right) .$ ### J~k~(n) -- Jordan totient function {#jkn_jordan_totient_function} **J~k~(n)*, the Jordan totient function, is the number of k-tuples of positive integers all less than or equal to n* that form a coprime (k + 1)-tuple together with n. It is a generalization of Euler\'s totient, `{{math\|1=''φ''(''n'') = ''J''<sub>1</sub>(''n'')}}`{=mediawiki}. $J_k(n) = n^k \prod_{p\mid n} \left(1-\frac{1}{p^k}\right) = n^k \left(\frac{p^k_1 - 1}{p^k_1}\right)\left(\frac{p^k_2 - 1}{p^k_2}\right) \cdots \left(\frac{p^k_{\omega(n)} - 1}{p^k_{\omega(n)}}\right) .$ ### μ(n) -- Möbius function {#μn_möbius_function} **μ(n)*, the Möbius function, is important because of the Möbius inversion formula. See `{{slink\|#Dirichlet convolution}}`{=mediawiki}, below. $\mu(n)=\begin{cases} (-1)^{\omega(n)}=(-1)^{\Omega(n)} &\text{if }\; \omega(n) = \Omega(n)\\ 0&\text{if }\;\omega(n) \ne \Omega(n). \end{cases}$ This implies that μ(1) = 1. (Because Ω(1) = ω(1) = 0.) ### τ(n) -- Ramanujan tau function {#τn_ramanujan_tau_function} *τ(n)*, the Ramanujan tau function, is defined by its generating function identity: $\sum_{n\geq 1}\tau(n)q^n=q\prod_{n\geq 1}(1-q^n)^{24}.$ Although it is hard to say exactly what \"arithmetical property of n\" it \"expresses\", (τ(n) is (2π)^−12^ times the nth Fourier coefficient in the q-expansion of the modular discriminant function) it is included among the arithmetical functions because it is multiplicative and it occurs in identities involving certain σ~k~(n) and r~k~(n) functions (because these are also coefficients in the expansion of modular forms). ### c~q~(n) -- Ramanujan\'s sum {#cqn_ramanujans_sum} *c~q~(n)*, Ramanujan\'s sum, is the sum of the nth powers of the primitive qth roots of unity: $c_q(n) = \sum_{\stackrel{1\le a\le q}{ \gcd(a,q)=1}} e^{2 \pi i \tfrac{a}{q} n}.$ Even though it is defined as a sum of complex numbers (irrational for most values of q), it is an integer. For a fixed value of n* it is multiplicative in q: : *If q* and r are coprime*, then $c_q(n)c_r(n)=c_{qr}(n).$ ### ψ(n) -- Dedekind psi function {#ψn_dedekind_psi_function} The Dedekind psi function, used in the theory of modular functions, is defined by the formula $\psi(n) = n \prod_{p\|n}\left(1+\frac{1}{p}\right).$ ## Completely multiplicative functions {#completely_multiplicative_functions} ### λ(n) -- Liouville function {#λn_liouville_function} *λ(n)*, the Liouville function, is defined by $\lambda (n) = (-1)^{\Omega(n)}.$ ### χ(n) -- characters {#χn_characters} All Dirichlet characters χ(n)* are completely multiplicative. Two characters have special notations: The *principal character (mod n)* is denoted by χ~0~(a) (or χ~1~(a)). It is defined as $\chi_0(a) = \begin{cases} 1 & \text{if } \gcd(a,n) = 1, \\ 0 & \text{if } \gcd(a,n) \ne 1. \end{cases}$ The *quadratic character (mod n)* is denoted by the Jacobi symbol for odd n (it is not defined for even n): $\left(\frac{a}{n}\right) = \left(\frac{a}{p_1}\right)^{a_1}\left(\frac{a}{p_2}\right)^{a_2}\cdots \left(\frac{a}{p_{\omega(n)}}\right)^{a_{\omega(n)}}.$ In this formula $(\tfrac{a}{p})$ is the Legendre symbol, defined for all integers a and all odd primes p by $\left(\frac{a}{p}\right) = \begin{cases} \;\;\,0 & \text{if } a \equiv 0 \pmod p, \\+1 & \text{if }a \not\equiv 0\pmod p \text{ and for some integer }x, \;a\equiv x^2\pmod p \\-1 & \text{if there is no such } x. \end{cases}$ Following the normal convention for the empty product, $\left(\frac{a}{1}\right) = 1.$ ## Additive functions {#additive_functions} ### ω(n) -- distinct prime divisors {#ωn_distinct_prime_divisors} **ω(n)*, defined above as the number of distinct primes dividing n, is additive (see Prime omega function). ## Completely additive functions {#completely_additive_functions} ### Ω(n) -- prime divisors {#ωn_prime_divisors} Ω(n), defined above as the number of prime factors of n* counted with multiplicities, is completely additive (see Prime omega function). ### ν~p~(n) -- p-adic valuation of an integer n {#νpn_p_adic_valuation_of_an_integer_n} For a fixed prime p, **ν~p~(n)*, defined above as the exponent of the largest power of p* dividing n, is completely additive. ### Logarithmic derivative {#logarithmic_derivative} $\operatorname{ld}(n)=\frac{D(n)}{n} = \sum_{\stackrel{p\mid n}{p\text{ prime}}} \frac {v_p(n)} {p}$, where $D(n)$ is the arithmetic derivative. ## Neither multiplicative nor additive {#neither_multiplicative_nor_additive} ### π(x), Π(x), ϑ(x), ψ(x) -- prime-counting functions {#πx_πx_ϑx_ψx_prime_counting_functions} These important functions (which are not arithmetic functions) are defined for non-negative real arguments, and are used in the various statements and proofs of the prime number theorem. They are summation functions (see the main section just below) of arithmetic functions which are neither multiplicative nor additive. π(x), the prime-counting function, is the number of primes not exceeding x. It is the summation function of the characteristic function of the prime numbers. $\pi(x) = \sum_{p \le x} 1$ A related function counts prime powers with weight 1 for primes, 1/2 for their squares, 1/3 for cubes, etc. It is the summation function of the arithmetic function which takes the value 1/k on integers which are the kth power of some prime number, and the value 0 on other integers. $\Pi(x) = \sum_{p^k\le x}\frac{1}{k}.$ ϑ(x) and ψ(x), the Chebyshev functions, are defined as sums of the natural logarithms of the primes not exceeding x. $\vartheta(x)=\sum_{p\le x} \log p,$ $\psi(x) = \sum_{p^k\le x} \log p.$ The second Chebyshev function ψ(x) is the summation function of the von Mangoldt function just below. ### Λ(n) -- von Mangoldt function {#λn_von_mangoldt_function} *Λ(n), the von Mangoldt function, is 0 unless the argument n* is a prime power `{{math\|''p''<sup>''k''</sup>}}`{=mediawiki}, in which case it is the natural logarithm of the prime p: $\Lambda(n) = \begin{cases} \log p &\text{if } n = 2,3,4,5,7,8,9,11,13,16,\ldots=p^k \text{ is a prime power}\\ 0&\text{if } n=1,6,10,12,14,15,18,20,21,\dots \;\;\;\;\text{ is not a prime power}. \end{cases}$ ### p(n) -- partition function {#pn_partition_function} **p(n)*, the partition function, is the number of ways of representing n* as a sum of positive integers, where two representations with the same summands in a different order are not counted as being different: $p(n) = \left\|\left\{ (a_1, a_2,\dots a_k): 0 < a_1 \le a_2 \le \cdots \le a_k\; \land \;n=a_1+a_2+\cdots +a_k \right\}\right\|.$ ### λ(n) -- Carmichael function {#λn_carmichael_function} **λ(n)*, the Carmichael function, is the smallest positive number such that $a^{\lambda(n)}\equiv 1 \pmod{n}$ for all a* coprime to n. Equivalently, it is the least common multiple of the orders of the elements of the multiplicative group of integers modulo n. For powers of odd primes and for 2 and 4, λ(n) is equal to the Euler totient function of n; for powers of 2 greater than 4 it is equal to one half of the Euler totient function of n: $\lambda(n) = \begin{cases} \;\;\phi(n) &\text{if }n = 2,3,4,5,7,9,11,13,17,19,23,25,27,\dots\\ \tfrac 1 2 \phi(n)&\text{if }n=8,16,32,64,\dots \end{cases}$ and for general n it is the least common multiple of λ of each of the prime power factors of n: $\lambda(p_1^{a_1}p_2^{a_2} \dots p_{\omega(n)}^{a_{\omega(n)}}) = \operatorname{lcm}[\lambda(p_1^{a_1}),\;\lambda(p_2^{a_2}),\dots,\lambda(p_{\omega(n)}^{a_{\omega(n)}}) ].$ ### h(n) -- class number {#hn_class_number} **h(n)*, the class number function, is the order of the ideal class group of an algebraic extension of the rationals with discriminant n. The notation is ambiguous, as there are in general many extensions with the same discriminant. See quadratic field and cyclotomic field for classical examples. ### r~k~(n) -- sum of k* squares {#rkn_sum_of_k_squares} **r~k~(n)** is the number of ways n can be represented as the sum of k squares, where representations that differ only in the order of the summands or in the signs of the square roots are counted as different. $r_k(n) = \left\|\left\{(a_1, a_2,\dots,a_k):n=a_1^2+a_2^2+\cdots+a_k^2\right\}\right\|$ ### D(n) -- Arithmetic derivative {#dn_arithmetic_derivative} Using the Heaviside notation for the derivative, the arithmetic derivative D(n) is a function such that - $D(n) = 1$ if n prime, and - $D(mn) = m D(n) + D(m) n$ (the product rule) ## Summation functions {#summation_functions} Given an arithmetic function a(n), its summation function A(x) is defined by $A(x) := \sum_{n \le x} a(n) .$ A can be regarded as a function of a real variable. Given a positive integer m, A is constant along open intervals m \< x \< m + 1, and has a jump discontinuity at each integer for which a(m) ≠ 0. Since such functions are often represented by series and integrals, to achieve pointwise convergence it is usual to define the value at the discontinuities as the average of the values to the left and right: $A_0(m) := \frac 1 2 \left(\sum_{n < m} a(n) +\sum_{n \le m} a(n)\right) = A(m) - \frac 1 2 a(m) .$ Individual values of arithmetic functions may fluctuate wildly -- as in most of the above examples. Summation functions \"smooth out\" these fluctuations. In some cases it may be possible to find asymptotic behaviour for the summation function for large x. A classical example of this phenomenon is given by the divisor summatory function, the summation function of d(n), the number of divisors of n: $\liminf_{n\to\infty} d(n) = 2$ $\limsup_{n\to\infty}\frac{\log d(n) \log\log n}{\log n} = \log 2$ $\lim_{n\to\infty}\frac{d(1) + d(2)+ \cdots +d(n)}{\log(1) + \log(2)+ \cdots +\log(n)} = 1.$ An average order of an arithmetic function is some simpler or better-understood function which has the same summation function asymptotically, and hence takes the same values \"on average\". We say that g is an average order of f if $\sum_{n \le x} f(n) \sim \sum_{n \le x} g(n)$ as x tends to infinity. The example above shows that d(n) has the average order log(n). ## Dirichlet convolution {#dirichlet_convolution} Given an arithmetic function a(n), let F~a~(s), for complex s, be the function defined by the corresponding Dirichlet series (where it converges): $F_a(s) := \sum_{n=1}^\infty \frac{a(n)}{n^s} .$ F~a~(s) is called a generating function of a(n). The simplest such series, corresponding to the constant function a(n) = 1 for all n, is ζ(s) the Riemann zeta function. The generating function of the Möbius function is the inverse of the zeta function: $\zeta(s)\,\sum_{n=1}^\infty\frac{\mu(n)}{n^s}=1, \;\;\Re s >1.$ Consider two arithmetic functions a and b and their respective generating functions F~a~(s) and F~b~(s). The product F~a~(s)F~b~(s) can be computed as follows: $F_a(s)F_b(s) = \left( \sum_{m=1}^{\infty}\frac{a(m)}{m^s} \right)\left( \sum_{n=1}^{\infty}\frac{b(n)}{n^s} \right) .$ It is a straightforward exercise to show that if c(n) is defined by $c(n) := \sum_{ij = n} a(i)b(j) = \sum_{i\mid n}a(i)b\left(\frac{n}{i}\right) ,$ then $F_c(s) = F_a(s) F_b(s).$ This function c is called the Dirichlet convolution of a and b, and is denoted by $ab$. A particularly important case is convolution with the constant function a(n) = 1 for all n, corresponding to multiplying the generating function by the zeta function: $g(n) = \sum_{d \mid n}f(d).$ Multiplying by the inverse of the zeta function gives the Möbius inversion formula: $f(n) = \sum_{d\mid n}\mu\left(\frac{n}{d}\right)g(d).$ If f* is multiplicative, then so is g. If f is completely multiplicative, then g is multiplicative, but may or may not be completely multiplicative. ## Relations among the functions {#relations_among_the_functions} There are a great many formulas connecting arithmetical functions with each other and with the functions of analysis, especially powers, roots, and the exponential and log functions. The page divisor sum identities contains many more generalized and related examples of identities involving arithmetic functions. Here are a few examples: ### Dirichlet convolutions {#dirichlet_convolutions} : \\sum\_{\\delta\\mid n}\\mu(\\delta)= \\sum\_{\\delta\\mid n}\\lambda\\left(\\frac{n}{\\delta}\\right)\\|\\mu(\\delta)\\|= \\begin{cases} 1 & \\text{if } n=1\\\\ 0 & \\text{if } n\\ne1 \\end{cases} where λ is the Liouville function. : $\sum_{\delta\mid n}\varphi(\delta) = n.$ : \\varphi(n) # \\sum\_{\\delta\\mid n}\\mu\\left(\\frac{n}{\\delta}\\right)\\delta {#sum_deltamid_nmuleftfracndeltarightdelta} n\\sum\_{\\delta\\mid n}\\frac{\\mu(\\delta)}{\\delta}. Möbius inversion : $\sum_{d \mid n } J_k(d) = n^k.$ : J_k(n) # \\sum\_{\\delta\\mid n}\\mu\\left(\\frac{n}{\\delta}\\right)\\delta\^k {#sum_deltamid_nmuleftfracndeltarightdeltak} n\^k\\sum\_{\\delta\\mid n}\\frac{\\mu(\\delta)}{\\delta\^k}. Möbius inversion : $\sum_{\delta\mid n}\delta^sJ_r(\delta)J_s\left(\frac{n}{\delta}\right) = J_{r+s}(n)$ : $\sum_{\delta\mid n}\varphi(\delta)d\left(\frac{n}{\delta}\right) = \sigma(n).$ : $\sum_{\delta\mid n}\|\mu(\delta)\| = 2^{\omega(n)}.$ : $\|\mu(n)\|=\sum_{\delta\mid n}\mu\left(\frac{n}{\delta}\right)2^{\omega(\delta)}.$ Möbius inversion : $\sum_{\delta\mid n}2^{\omega(\delta)}=d(n^2).$ : $2^{\omega(n)}=\sum_{\delta\mid n}\mu\left(\frac{n}{\delta}\right)d(\delta^2).$ Möbius inversion : $\sum_{\delta\mid n}d(\delta^2)=d^2(n).$ : $d(n^2)=\sum_{\delta\mid n}\mu\left(\frac{n}{\delta}\right)d^2(\delta).$ Möbius inversion : $\sum_{\delta\mid n}d\left(\frac{n}{\delta}\right)2^{\omega(\delta)}=d^2(n).$ : \\sum\_{\\delta\\mid n}\\lambda(\\delta)=\\begin{cases} &1\\text{ if } n \\text{ is a square }\\\\ &0\\text{ if } n \\text{ is not square.} \\end{cases} where λ is the Liouville function. : $\sum_{\delta\mid n}\Lambda(\delta) = \log n.$ : $\Lambda(n)=\sum_{\delta\mid n}\mu\left(\frac{n}{\delta}\right)\log(\delta).$ Möbius inversion ### Sums of squares {#sums_of_squares} For all $k \ge 4,\;\;\; r_k(n) > 0.$ (Lagrange\'s four-square theorem). : r_2(n) = 4\\sum\_{d\\mid n}\\left(\\frac{-4}{d}\\right), where the Kronecker symbol has the values : \\left(\\frac{-4}{n}\\right) = \\begin{cases} +1&\\text{if }n\\equiv 1 \\pmod 4 \\\\ -1&\\text{if }n\\equiv 3 \\pmod 4\\\\ \\;\\;\\;0&\\text{if }n\\text{ is even}.\\\\ \\end{cases} There is a formula for r~3~ in the section on class numbers below. $r_4(n) = 8 \sum_{\stackrel{d\mid n}{ 4\, \nmid \,d}}d = 8 (2+(-1)^n)\sum_{\stackrel{d\mid n}{ 2\, \nmid \,d}}d = \begin{cases} 8\sigma(n)&\text{if } n \text{ is odd }\\ 24\sigma\left(\frac{n}{2^\nu}\right)&\text{if } n \text{ is even } \end{cases},$ where `{{math\|1=''ν'' = ''ν''<sub>2</sub>(''n'')}}`{=mediawiki}. $r_6(n) = 16 \sum_{d\mid n} \chi\left(\frac{n}{d}\right)d^2 - 4\sum_{d\mid n} \chi(d)d^2,$ where $\chi(n) = \left(\frac{-4}{n}\right).$ Define the function `{{math\|1=''σ''<sub>''k''</sub><sup></sup>(''n'')}}`{=mediawiki} as $\sigma_k^(n) = (-1)^{n}\sum_{d\mid n}(-1)^d d^k= \begin{cases} \sum_{d\mid n} d^k=\sigma_k(n)&\text{if } n \text{ is odd }\\ \sum_{\stackrel{d\mid n}{ 2\, \mid \,d}}d^k -\sum_{\stackrel{d\mid n}{ 2\, \nmid \,d}}d^k&\text{if } n \text{ is even}. \end{cases}$ That is, if n is odd, `{{math\|1=''σ''<sub>''k''</sub><sup></sup>(''n'')}}`{=mediawiki} is the sum of the kth powers of the divisors of n, that is, `{{math\|1=''σ''<sub>''k''</sub>(''n''),}}`{=mediawiki} and if n* is even it is the sum of the kth powers of the even divisors of n minus the sum of the kth powers of the odd divisors of n. : $r_8(n) = 16\sigma_3^(n).$ Adopt the convention that Ramanujan\'s `{{math\|1=''τ''(''x'') = 0}}`{=mediawiki} if x* is not an integer. : r\_{24}(n) = \\frac{16}{691}\\sigma\_{11}\^\(n) + \\frac{128}{691}\\left\\{ (-1)\^{n-1}259\\tau(n)-512\\tau\\left(\\frac{n}{2}\\right)\\right\\} ### Divisor sum convolutions {#divisor_sum_convolutions} Here \"convolution\" does not mean \"Dirichlet convolution\" but instead refers to the formula for the coefficients of the product of two power series: : \\left(\\sum\_{n=0}\^\\infty a_n x\^n\\right)\\left(\\sum\_{n=0}\^\\infty b_n x\^n\\right) # \\sum\_{i 0}\^\\infty \\sum\_{j=0}\^\\infty a_i b_j x\^{i+j} # \\sum\_{n 0}\^\\infty \\left(\\sum\_{i=0}\^n a_i b\_{n-i}\\right) x\^n # \\sum\_{n {#sum_n_1} 0}\^\\infty c_n x\^n . The sequence $c_n = \sum_{i=0}^n a_i b_{n-i}$ is called the convolution or the Cauchy product of the sequences a~n~ and b~n~. `{{br}}`{=mediawiki}These formulas may be proved analytically (see Eisenstein series) or by elementary methods. : \\sigma_3(n) = \\frac{1}{5}\\left\\{6n\\sigma_1(n)-\\sigma_1(n) + 12\\sum\_{0\<k\<n}\\sigma_1(k)\\sigma_1(n-k)\\right\\}. : \\sigma_5(n) = \\frac{1}{21}\\left\\{10(3n-1)\\sigma_3(n)+\\sigma_1(n) + 240\\sum\_{0\<k\<n}\\sigma_1(k)\\sigma_3(n-k)\\right\\}. : \\begin{align} \\sigma_7(n) &=\\frac{1}{20}\\left\\{21(2n-1)\\sigma_5(n)-\\sigma_1(n) + 504\\sum\_{0\<k\<n}\\sigma_1(k)\\sigma_5(n-k)\\right\\}\\\\ &=\\sigma_3(n) + 120\\sum\_{0\<k\<n}\\sigma_3(k)\\sigma_3(n-k). \\end{align} : \\begin{align} \\sigma_9(n) &= \\frac{1}{11}\\left\\{10(3n-2)\\sigma_7(n)+\\sigma_1(n) + 480\\sum\_{0\<k\<n}\\sigma_1(k)\\sigma_7(n-k)\\right\\}\\\\ &= \\frac{1}{11}\\left\\{21\\sigma_5(n)-10\\sigma_3(n) + 5040\\sum\_{0\<k\<n}\\sigma_3(k)\\sigma_5(n-k)\\right\\}. \\end{align} : \\tau(n) = \\frac{65}{756}\\sigma\_{11}(n) + \\frac{691}{756}\\sigma\_{5}(n) - \\frac{691}{3}\\sum\_{0\<k\<n}\\sigma_5(k)\\sigma_5(n-k), where τ(n) is Ramanujan\'s function. Since σ~k~(n) (for natural number k) and τ(n) are integers, the above formulas can be used to prove congruences for the functions. See Ramanujan tau function for some examples. Extend the domain of the partition function by setting `{{math\|1=''p''(0) = 1.}}`{=mediawiki} : p(n)=\\frac{1}{n}\\sum\_{1\\le k\\le n}\\sigma(k)p(n-k). This recurrence can be used to compute p(n). ### Class number related {#class_number_related} Peter Gustav Lejeune Dirichlet discovered formulas that relate the class number h* of quadratic number fields to the Jacobi symbol. An integer D is called a fundamental discriminant if it is the discriminant of a quadratic number field. This is equivalent to D ≠ 1 and either a) D is squarefree and D ≡ 1 (mod 4) or b) D ≡ 0 (mod 4), D/4 is squarefree, and D/4 ≡ 2 or 3 (mod 4). Extend the Jacobi symbol to accept even numbers in the \"denominator\" by defining the Kronecker symbol: $\left(\frac{a}{2}\right) = \begin{cases} \;\;\,0&\text{ if } a \text{ is even} \\(-1)^{\frac{a^2-1}{8}}&\text{ if }a \text{ is odd. } \end{cases}$ Then if D \< −4 is a fundamental discriminant $\begin{align} h(D) & = \frac{1}{D} \sum_{r=1}^{\|D\|}r\left(\frac{D}{r}\right)\\ & = \frac{1}{2-\left(\tfrac{D}{2}\right)} \sum_{r=1}^{\|D\|/2}\left(\frac{D}{r}\right). \end{align}$ There is also a formula relating r~3~ and h. Again, let D be a fundamental discriminant, D \< −4. Then $r_3(\|D\|) = 12\left(1-\left(\frac{D}{2}\right)\right)h(D).$ ### Prime-count related {#prime_count_related} Let $H_n = 1 + \frac 1 2 + \frac 1 3 + \cdots +\frac{1}{n}$ be the nth harmonic number. Then : $\sigma(n) \le H_n + e^{H_n}\log H_n$ is true for every natural number n if and only if the Riemann hypothesis is true. The Riemann hypothesis is also equivalent to the statement that, for all n \> 5040, $\sigma(n) < e^\gamma n \log \log n$ (where γ is the Euler--Mascheroni constant). This is Robin\'s theorem. : $\sum_{p}\nu_p(n) = \Omega(n).$ : $\psi(x)=\sum_{n\le x}\Lambda(n).$ : $\Pi(x)= \sum_{n\le x}\frac{\Lambda(n)}{\log n}.$ : $e^{\theta(x)}=\prod_{p\le x}p.$ : $e^{\psi(x)}= \operatorname{lcm}[1,2,\dots,\lfloor x\rfloor].$ ### Menon\'s identity {#menons_identity} In 1965 P Kesava Menon proved $\sum_{\stackrel{1\le k\le n}{ \gcd(k,n)=1}} \gcd(k-1,n)=\varphi(n)d(n).$ This has been generalized by a number of mathematicians. For example, - B. Sury \\sum\_{\\stackrel{1\\le k_1, k_2, \\dots, k_s\\le n}{ \\gcd(k_1,n)=1}} \\gcd(k_1-1,k_2,\\dots,k_s,n) = \\varphi(n)\\sigma\_{s-1}(n). - N. Rao \\sum\_{\\stackrel{1\\le k_1, k_2, \\dots, k_s\\le n}{ \\gcd(k_1,k_2,\\dots,k_s,n)=1}} \\gcd(k_1-a_1,k_2-a_2,\\dots,k_s-a_s,n)\^s # J_s(n)d(n), where a~1~, a~2~, \..., a~s~ are integers, gcd(a~1~, a~2~, \..., a~s~, n) {#j_sndn_where_a1_a2_..._as_are_integers_gcda1_a2_..._as_n} 1\. - László Fejes Tóth \\sum\_{\\stackrel{1\\le k\\le m}{ \\gcd(k,m)=1}} \\gcd(k\^2-1,m_1)\\gcd(k\^2-1,m_2) # \\varphi(n)\\sum\_{\\stackrel{d_1\\mid m_1} {d_2\\mid m_2}} \\varphi(\\gcd(d_1, d_2))2\^{\\omega(\\operatorname{lcm}(d_1, d_2))}, where m~1~ and m~2~ are odd, m {#varphinsum_stackreld_1mid_m_1_d_2mid_m_2_varphigcdd_1_d_22omegaoperatornamelcmd_1_d_2_where_m1_and_m2_are_odd_m} lcm(m~1~, m~2~). In fact, if f is any arithmetical function $\sum_{\stackrel{1\le k\le n}{ \gcd(k,n)=1}} f(\gcd(k-1,n)) =\varphi(n)\sum_{d\mid n}\frac{(\muf)(d)}{\varphi(d)},$ where $$ stands for Dirichlet convolution. ### Miscellaneous Let m and n be distinct, odd, and positive. Then the Jacobi symbol satisfies the law of quadratic reciprocity: $\left(\frac{m}{n}\right) \left(\frac{n}{m}\right) = (-1)^{(m-1)(n-1)/4}.$ Let D(n) be the arithmetic derivative. Then the logarithmic derivative $\frac{D(n)}{n} = \sum_{\stackrel{p\mid n}{p\text{ prime}}} \frac {v_{p}(n)} {p}.$ See Arithmetic derivative for details. Let λ(n) be Liouville\'s function. Then : $\|\lambda(n)\|\mu(n) =\lambda(n)\|\mu(n)\| = \mu(n),$ and : $\lambda(n)\mu(n) = \|\mu(n)\| =\mu^2(n).$ Let λ(n) be Carmichael\'s function. Then : $\lambda(n)\mid \phi(n).$ Further, : \\lambda(n)= \\phi(n) \\text{ if and only if }n=\\begin{cases} 1,2, 4;\\\\ 3,5,7,9,11, \\ldots \\text{ (that is, } p\^k \\text{, where }p\\text{ is an odd prime)};\\\\ 6,10,14,18,\\ldots \\text{ (that is, } 2p\^k\\text{, where }p\\text{ is an odd prime)}. \\end{cases} See Multiplicative group of integers modulo n and Primitive root modulo n. : $2^{\omega(n)} \le d(n) \le 2^{\Omega(n)}.$ : $\frac{6}{\pi^2}<\frac{\phi(n)\sigma(n)}{n^2} < 1.$ : \\begin{align} c_q(n) &=\\frac{\\mu\\left(\\frac{q}{\\gcd(q, n)}\\right)}{\\phi\\left(\\frac{q}{\\gcd(q, n)}\\right)}\\phi(q)\\\\ &=\\sum\_{\\delta\\mid \\gcd(q,n)}\\mu\\left(\\frac{q}{\\delta}\\right)\\delta. \\end{align} Note that $\phi(q) = \sum_{\delta\mid q}\mu\left(\frac{q}{\delta}\right)\delta.$ : $c_q(1) = \mu(q).$ : $c_q(q) = \phi(q).$ : $\sum_{\delta\mid n}d^{3}(\delta) = \left(\sum_{\delta\mid n}d(\delta)\right)^2.$ Compare this with `{{math\|1=1<sup>3</sup> + 2<sup>3</sup> + 3<sup>3</sup> + ... + ''n''<sup>3</sup> = (1 + 2 + 3 + ... + ''n'')<sup>2</sup>}}`{=mediawiki} : d(uv) = \\sum\_{\\delta\\mid \\gcd(u,v)}\\mu(\\delta)d\\left(\\frac{u}{\\delta}\\right)d\\left(\\frac{v}{\\delta}\\right). : \\sigma_k(u)\\sigma_k(v) = \\sum\_{\\delta\\mid \\gcd(u,v)}\\delta\^k\\sigma_k\\left(\\frac{uv}{\\delta\^2}\\right). : \\tau(u)\\tau(v) = \\sum\_{\\delta\\mid \\gcd(u,v)}\\delta\^{11}\\tau\\left(\\frac{uv}{\\delta\^2}\\right), where τ(n) is Ramanujan\'s function. ## First 100 values of some arithmetic functions {#first_100_values_of_some_arithmetic_functions} n factorization φ(n) ω(n) Ω(n) λ(n) μ(n) Λ(n) π(n) σ~0~(n) σ~1~(n) σ~2~(n) r~2~(n) r~3~(n) r~4~(n) ----- --------------- ---------- ---------- -------- ---------- ---------- -------- ---------- ------------- ------------- ------------- ------------- ------------- ------------- 1 1 1 0 0 1 1 0 0 1 1 1 4 6 8 2 2 1 1 1 −1 −1 0.69 1 2 3 5 4 12 24 3 3 2 1 1 −1 −1 1.10 2 2 4 10 0 8 32 4 2^2^ 2 1 2 1 0 0.69 2 3 7 21 4 6 24 5 5 4 1 1 −1 −1 1.61 3 2 6 26 8 24 48 6 2 · 3 2 2 2 1 1 0 3 4 12 50 0 24 96 7 7 6 1 1 −1 −1 1.95 4 2 8 50 0 0 64 8 2^3^ 4 1 3 −1 0 0.69 4 4 15 85 4 12 24 9 3^2^ 6 1 2 1 0 1.10 4 3 13 91 4 30 104 10 2 · 5 4 2 2 1 1 0 4 4 18 130 8 24 144 11 11 10 1 1 −1 −1 2.40 5 2 12 122 0 24 96 12 2^2^ · 3 4 2 3 −1 0 0 5 6 28 210 0 8 96 13 13 12 1 1 −1 −1 2.56 6 2 14 170 8 24 112 14 2 · 7 6 2 2 1 1 0 6 4 24 250 0 48 192 15 3 · 5 8 2 2 1 1 0 6 4 24 260 0 0 192 16 2^4^ 8 1 4 1 0 0.69 6 5 31 341 4 6 24 17 17 16 1 1 −1 −1 2.83 7 2 18 290 8 48 144 18 2 · 3^2^ 6 2 3 −1 0 0 7 6 39 455 4 36 312 19 19 18 1 1 −1 −1 2.94 8 2 20 362 0 24 160 20 2^2^ · 5 8 2 3 −1 0 0 8 6 42 546 8 24 144 21 3 · 7 12 2 2 1 1 0 8 4 32 500 0 48 256 22 2 · 11 10 2 2 1 1 0 8 4 36 610 0 24 288 23 23 22 1 1 −1 −1 3.14 9 2 24 530 0 0 192 24 2^3^ · 3 8 2 4 1 0 0 9 8 60 850 0 24 96 25 5^2^ 20 1 2 1 0 1.61 9 3 31 651 12 30 248 26 2 · 13 12 2 2 1 1 0 9 4 42 850 8 72 336 27 3^3^ 18 1 3 −1 0 1.10 9 4 40 820 0 32 320 28 2^2^ · 7 12 2 3 −1 0 0 9 6 56 1050 0 0 192 29 29 28 1 1 −1 −1 3.37 10 2 30 842 8 72 240 30 2 · 3 · 5 8 3 3 −1 −1 0 10 8 72 1300 0 48 576 31 31 30 1 1 −1 −1 3.43 11 2 32 962 0 0 256 32 2^5^ 16 1 5 −1 0 0.69 11 6 63 1365 4 12 24 33 3 · 11 20 2 2 1 1 0 11 4 48 1220 0 48 384 34 2 · 17 16 2 2 1 1 0 11 4 54 1450 8 48 432 35 5 · 7 24 2 2 1 1 0 11 4 48 1300 0 48 384 36 2^2^ · 3^2^ 12 2 4 1 0 0 11 9 91 1911 4 30 312 37 37 36 1 1 −1 −1 3.61 12 2 38 1370 8 24 304 38 2 · 19 18 2 2 1 1 0 12 4 60 1810 0 72 480 39 3 · 13 24 2 2 1 1 0 12 4 56 1700 0 0 448 40 2^3^ · 5 16 2 4 1 0 0 12 8 90 2210 8 24 144 41 41 40 1 1 −1 −1 3.71 13 2 42 1682 8 96 336 42 2 · 3 · 7 12 3 3 −1 −1 0 13 8 96 2500 0 48 768 43 43 42 1 1 −1 −1 3.76 14 2 44 1850 0 24 352 44 2^2^ · 11 20 2 3 −1 0 0 14 6 84 2562 0 24 288 45 3^2^ · 5 24 2 3 −1 0 0 14 6 78 2366 8 72 624 46 2 · 23 22 2 2 1 1 0 14 4 72 2650 0 48 576 47 47 46 1 1 −1 −1 3.85 15 2 48 2210 0 0 384 48 2^4^ · 3 16 2 5 −1 0 0 15 10 124 3410 0 8 96 49 7^2^ 42 1 2 1 0 1.95 15 3 57 2451 4 54 456 50 2 · 5^2^ 20 2 3 −1 0 0 15 6 93 3255 12 84 744 51 3 · 17 32 2 2 1 1 0 15 4 72 2900 0 48 576 52 2^2^ · 13 24 2 3 −1 0 0 15 6 98 3570 8 24 336 53 53 52 1 1 −1 −1 3.97 16 2 54 2810 8 72 432 54 2 · 3^3^ 18 2 4 1 0 0 16 8 120 4100 0 96 960 55 5 · 11 40 2 2 1 1 0 16 4 72 3172 0 0 576 56 2^3^ · 7 24 2 4 1 0 0 16 8 120 4250 0 48 192 57 3 · 19 36 2 2 1 1 0 16 4 80 3620 0 48 640 58 2 · 29 28 2 2 1 1 0 16 4 90 4210 8 24 720 59 59 58 1 1 −1 −1 4.08 17 2 60 3482 0 72 480 60 2^2^ · 3 · 5 16 3 4 1 0 0 17 12 168 5460 0 0 576 61 61 60 1 1 −1 −1 4.11 18 2 62 3722 8 72 496 62 2 · 31 30 2 2 1 1 0 18 4 96 4810 0 96 768 63 3^2^ · 7 36 2 3 −1 0 0 18 6 104 4550 0 0 832 64 2^6^ 32 1 6 1 0 0.69 18 7 127 5461 4 6 24 65 5 · 13 48 2 2 1 1 0 18 4 84 4420 16 96 672 66 2 · 3 · 11 20 3 3 −1 −1 0 18 8 144 6100 0 96 1152 67 67 66 1 1 −1 −1 4.20 19 2 68 4490 0 24 544 68 2^2^ · 17 32 2 3 −1 0 0 19 6 126 6090 8 48 432 69 3 · 23 44 2 2 1 1 0 19 4 96 5300 0 96 768 70 2 · 5 · 7 24 3 3 −1 −1 0 19 8 144 6500 0 48 1152 71 71 70 1 1 −1 −1 4.26 20 2 72 5042 0 0 576 72 2^3^ · 3^2^ 24 2 5 −1 0 0 20 12 195 7735 4 36 312 73 73 72 1 1 −1 −1 4.29 21 2 74 5330 8 48 592 74 2 · 37 36 2 2 1 1 0 21 4 114 6850 8 120 912 75 3 · 5^2^ 40 2 3 −1 0 0 21 6 124 6510 0 56 992 76 2^2^ · 19 36 2 3 −1 0 0 21 6 140 7602 0 24 480 77 7 · 11 60 2 2 1 1 0 21 4 96 6100 0 96 768 78 2 · 3 · 13 24 3 3 −1 −1 0 21 8 168 8500 0 48 1344 79 79 78 1 1 −1 −1 4.37 22 2 80 6242 0 0 640 80 2^4^ · 5 32 2 5 −1 0 0 22 10 186 8866 8 24 144 81 3^4^ 54 1 4 1 0 1.10 22 5 121 7381 4 102 968 82 2 · 41 40 2 2 1 1 0 22 4 126 8410 8 48 1008 83 83 82 1 1 −1 −1 4.42 23 2 84 6890 0 72 672 84 2^2^ · 3 · 7 24 3 4 1 0 0 23 12 224 10500 0 48 768 85 5 · 17 64 2 2 1 1 0 23 4 108 7540 16 48 864 86 2 · 43 42 2 2 1 1 0 23 4 132 9250 0 120 1056 87 3 · 29 56 2 2 1 1 0 23 4 120 8420 0 0 960 88 2^3^ · 11 40 2 4 1 0 0 23 8 180 10370 0 24 288 89 89 88 1 1 −1 −1 4.49 24 2 90 7922 8 144 720 90 2 · 3^2^ · 5 24 3 4 1 0 0 24 12 234 11830 8 120 1872 91 7 · 13 72 2 2 1 1 0 24 4 112 8500 0 48 896 92 2^2^ · 23 44 2 3 −1 0 0 24 6 168 11130 0 0 576 93 3 · 31 60 2 2 1 1 0 24 4 128 9620 0 48 1024 94 2 · 47 46 2 2 1 1 0 24 4 144 11050 0 96 1152 95 5 · 19 72 2 2 1 1 0 24 4 120 9412 0 0 960 96 2^5^ · 3 32 2 6 1 0 0 24 12 252 13650 0 24 96 97 97 96 1 1 −1 −1 4.57 25 2 98 9410 8 48 784 98 2 · 7^2^ 42 2 3 −1 0 0 25 6 171 12255 4 108 1368 99 3^2^ · 11 60 2 3 −1 0 0 25 6 156 11102 0 72 1248 100 2^2^ · 5^2^ 40 2 4 1 0 0 25 9 217 13671 12 30 744 n factorization φ(n) ω(n) Ω(n) (n) (n) Λ(n) π(n) σ~0~(n) σ~1~(n) σ~2~(n) r~2~(n) r~3~(n) r~4~(n)	2025-06-20T00:00:00
3,172	ANSI C	ANSI C, ISO C, and Standard C are successive standards for the C programming language published by the American National Standards Institute (ANSI) and ISO/IEC JTC 1/SC 22/WG 14 of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Historically, the names referred specifically to the original and best-supported version of the standard (known as C89 or C90). Software developers writing in C are encouraged to conform to the standards, as doing so helps portability between compilers. ## History and outlook {#history_and_outlook} The first standard for C was published by ANSI. Although this document was subsequently adopted by ISO/IEC and subsequent revisions published by ISO/IEC have been adopted by ANSI, \"ANSI C\" is still used to refer to the standard. While some software developers use the term ISO C, others are standards-body neutral and use Standard C. ### Informal specification: K&R C (C78) {#informal_specification_kr_c_c78} Informal specification in 1978 (Brian Kernighan and Dennis Ritchie book The C Programming Language). ### Standardizing C {#standardizing_c} In 1983, the American National Standards Institute formed a committee, X3J11, to establish a standard specification of C. In 1985, the first Standard Draft was released, sometimes referred to as C85. In 1986, another Draft Standard was released, sometimes referred to as C86. The prerelease Standard C was published in 1988, and sometimes referred to as C88. ### C89 The ANSI standard was completed in 1989 and ratified as ANSI X3.159-1989 \"Programming Language C.\" This version of the language is often referred to as \"ANSI C\". Later on sometimes the label \"C89\" is used to distinguish it from C90 but using the same labeling method. ### C90 The same standard as C89 was ratified by ISO/IEC as ISO/IEC 9899:1990, with only formatting changes, which is sometimes referred to as C90. Therefore, the terms \"C89\" and \"C90\" refer to a language that is virtually identical. This standard has been withdrawn by both ANSI/INCITS and ISO/IEC. ### C95 In 1995, the ISO/IEC published an extension, called Amendment 1, for the C standard. Its full name finally was ISO/IEC 9899:1990/AMD1:1995 or nicknamed C95. Aside from error correction there were further changes to the language capabilities, such as: - Improved multi-byte and wide character support in the standard library, introducing `<wchar.h>` and `<wctype.h>` as well as multi-byte I/O - Addition of digraphs to the language - Specification of standard macros for the alternative specification of operators, e.g. `and` for `&&` - Specification of the standard macro `__STDC_VERSION__` In addition to the amendment, two technical corrigenda were published by ISO for C90: - ISO/IEC 9899:1990/Cor 1:1994 TCOR1 in 1994 - ISO/IEC 9899:1990/Cor 2:1996 in 1996 #### Preprocessor test for C95 compatibility {#preprocessor_test_for_c95_compatibility} ``` c #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199409L /* C95 compatible source code. / #elif defined(__STDC__) / C89 compatible source code. / #endif ``` ### C99 In March 2000, ANSI adopted the ISO/IEC 9899:1999 standard. This standard is commonly referred to as C99. Some notable additions to the previous standard include: - New built-in data types: `long long`, `_Bool`, `_Complex`, and `_Imaginary` - Several new core language features, including static array indices, designated initializers, compound literals, variable-length arrays, flexible array members, variadic macros, and `restrict` keyword - Several new library headers, including `stdint.h`, `<tgmath.h>`, `fenv.h`, `<complex.h>` - Improved compatibility with several C++ features, including inline functions, single-line comments with `//`, mixing declarations and code, and universal character names in identifiers - Removed several dangerous C89 language features such as implicit function declarations and implicit `int` Three technical corrigenda were published by ISO for C99: - ISO/IEC 9899:1999/Cor 1:2001(E) - ISO/IEC 9899:1999/Cor 2:2004(E) - ISO/IEC 9899:1999/Cor 3:2007(E), notable for deprecating the standard library function gets This standard has been withdrawn by both ANSI/INCITS and ISO/IEC in favour of C11. ### C11 C11 was officially ratified and published on December 8, 2011. Notable features include improved Unicode support, type-generic expressions using the new `_Generic` keyword, a cross-platform multi-threading API (`threads.h`), and atomic types support in both core language and the library (`stdatomic.h`). One technical corrigendum has been published by ISO for C11: - ISO/IEC 9899:2011/Cor 1:2012 ### C17 C17 was published in June 2018. Rather than introducing new language features, it only addresses defects in C11. ### C23 C23 was published in October 2024, and is the current standard for the C programming language. ### Other related ISO publications {#other_related_iso_publications} As part of the standardization process, ISO/IEC also publishes technical reports and specifications related to the C language: - ISO/IEC TR 19769:2004, on library extensions to support Unicode transformation formats, integrated into C11 - ISO/IEC TR 24731-1:2007, on library extensions to support bounds-checked interfaces, integrated into C11 - ISO/IEC TR 18037:2008, on embedded C extensions - ISO/IEC TR 24732:2009, on decimal floating point arithmetic, superseded by ISO/IEC TS 18661-2:2015 - ISO/IEC TR 24747:2009, on special mathematical functions, - ISO/IEC TR 24731-2:2010, on library extensions to support dynamic allocation functions - ISO/IEC TS 17961:2013, on secure coding in C - ISO/IEC TS 18661-1:2014, on IEC 60559:2011-compatible binary floating-point arithmetic - ISO/IEC TS 18661-2:2015, on IEC 60559:2011-compatible decimal floating point arithmetic - ISO/IEC TS 18661-3:2015, on IEC 60559:2011-compatible interchange and extended floating-point types - ISO/IEC TS 18661-4:2015, on IEC 60559:2011-compatible supplementary functions More technical specifications are in development and pending approval, including the fifth and final part of TS 18661, a software transactional memory specification, and parallel library extensions. ## Support from major compilers {#support_from_major_compilers} ANSI C is supported by almost all the widely used compilers. GCC and Clang are two major C compilers popular today, both based on the C11 with updates including changes from later specifications such as C17. Any source code written only* in standard C and without any hardware dependent assumptions is virtually guaranteed to compile correctly on any platform with a conforming C implementation. Without such precautions, most programs may compile only on a certain platform or with a particular compiler, due, for example, to the use of non-standard libraries, such as GUI libraries, or to the reliance on compiler- or platform-specific attributes such as the exact size of certain data types and byte endianness. ### Compliance detectability {#compliance_detectability} To mitigate the differences between K&R C and the ANSI C standard, the `__STDC__` (\"standard c\") macro can be used to split code into ANSI and K&R sections. ``` c #if defined(__STDC__) && __STDC__ extern int getopt(int, char * const , const char ); #else extern int getopt(); #endif ``` In the above example, a prototype is used in a function declaration for ANSI compliant implementations, while an obsolescent non-prototype declaration is used otherwise. Those are still ANSI-compliant as of C99. Note how this code checks both definition and evaluation: this is because some implementations may set `__STDC__` to zero to indicate non-ANSI compliance. ## Compiler support {#compiler_support} List of compilers supporting ANSI C: - Acornsoft ANSI C (first version in 1988, revised in 1989) - Amsterdam Compiler Kit (C K&R and C89/90) - ARM RealView - Clang (full C89/C90, partial C99, C11, C17, C23 and C2y), using LLVM backend - GCC (full C89/90, C99, C11, partial C17 and some C23 and experimental/incomplete C2y) - HP C/ANSI C compiler (C89 and C99) - IBM XL C/C++ (C11, starting with version 12.1) - Intel\'s ICC (later versions are based on clang, and have its support!\-- or more or less, seemingly missing some support/or table wrong, not updated? And can have more support than clang despite when using it? \--\>) - LabWindows/CVI - LCC - Oracle Developer Studio - OpenWatcom (C89/90 and some C99) - Microsoft Visual C++ (C89/90 and some C99, C11, C17, mostly missing C23) - Pelles C (C99 and C11. Windows only.) - vbcc (C89/90 and C99) - Tiny C Compiler (C89/90 and some C99)	2025-06-20T00:00:00
3,175	Antinomy	In philosophy, an antinomy (Ancient Greek: antí \'against\' + nómos \'law\') is a real or apparent contradiction between two conclusions, both of which seem justified. It is a term used in logic and epistemology, particularly in the philosophy of Immanuel Kant. Antinomy is a common form of argument in the dialogues of Plato. Kant credited Zeno of Elea (see Zeno\'s paradoxes) as the inventor of the antinomic mode of argumentation, which he described as a \"skeptical method\" of \"watching, or rather provoking, a conflict of assertions, not for the purpose of deciding in favor of one or the other side, but of investigating whether the object of the controversy is not perhaps a deceptive appearance which each vainly tries to grasp, and in regard to which, even if there were no opposition to overcome, neither can arrive at any result\". The antinomic procedure was further developed by Fichte, Schelling and Hegel. Hegel said that Kant was in error when he limited the antinomies to cosmological ideas, claiming that the world itself contains contradiction. Schopenhauer said that the antitheses in Kant\'s antinomies were justified, but claimed the theses (cosmological propositions) to be sophisms. There are many examples of antinomy. A self-contradictory phrase such as \"There is no absolute truth\" can be considered an antinomy because this statement is suggesting in itself to be an absolute truth, and therefore denies itself any truth in its statement. It is not necessarily also a paradox. A paradox, such as \"this sentence is false,\" can also be considered to be an antinomy; in this case, for the sentence to be true, it must be false. ## Terminology Antinomies can be found in Plato, in substance though not by this name (cf. Phaedo 102; Rep. 523 ff., Parm. 135 E). Modern usage dates back to a 17th-century legal term, which acquired philosophical significance in Immanuel Kant\'s Critique of Pure Reason (CPR). In the Transcendental Dialectic, Kant defines an antinomy as a \"conflict of laws\" (CPR A407/B434). Kant\'s use of the term was derived from jurisprudence, where it refers to a conflict between laws, and from biblical exegesis, where it refers to conflict between passages of scripture. In modern logic, the term \"antinomy\" is not used consistently and is sometimes not clearly distinguished from the term paradox. In the German language, however, it is customary to reserve the term \"antinomy\" for contradictions that can be rigorously proven within the framework of a formal system and which thus indicate an error in the conception of the rules of inference or the axioms of that system (e.g. the antinomies of naive set theory, the best known being Russell\'s paradox). In contrast, a paradox (Ancient Greek παρά para \"beside, apart\" and δόξα doxa \"expectation, opinion\", παράδοξον paradoxon \"contrary to expectation, contrary to common opinion\") is usually used to describe a well-founded statement that contradicts conventional wisdom, but which does not cause any real logical difficulties. Many scientific insights can appear paradoxical in this harmless sense (e.g., the twin paradox in Einstein\'s theory of relativity or the so-called paradoxes of material implication in formal logic; see relevance logic). In English, the term antinomy is not particularly widespread and its application is mostly limited to Kantian antinomies. In modern logic, a \"contradiction\" is simply understood as the conjunction of a statement and its negation, i.e. a statement of the form $A \land \lnot A$ (read: \"A and not-A\"). This broad term is neutral with regard to the question of provability or justifiability, and includes, for example, contradictions that are derived within a proof by contradiction specifically for the purpose of negating one of the assumptions involved in the derivation. Therefore, not all contradiction is philosophically problematic. Separately from this usage, the word \"contradiction\" is also used in Hegelian dialectics, where it includes social conflict, antagonisms and such. ## Kant\'s use {#kants_use} The term acquired a special significance in the philosophy of Immanuel Kant (1724--1804), who used it to describe the equally rational but contradictory results of applying to the universe of pure thought the categories or criteria of reason that are proper to the universe of sensible perception or experience (phenomena). Empirical reason cannot here play the role of establishing rational truths because it goes beyond possible experience and is applied to the sphere of that which transcends it. For Kant there are four antinomies, connected with: - the limitation of the universe in respect to space and time - the theory that the whole consists of indivisible atoms (whereas, in fact, none such exist) - the problem of free will in relation to universal causality - the existence of a universal being In each antinomy, a thesis is contradicted by an antithesis. For example: in the first antinomy, Kant proves the thesis that time must have a beginning by showing that if time had no beginning, then an infinity would have elapsed up until the present moment. This is a manifest contradiction because infinity cannot, by definition, be completed by \"successive synthesis\"---yet just such a finalizing synthesis would be required by the view that time is infinite; so the thesis is proven. Then he proves the antithesis, that time has no beginning, by showing that if time had a beginning, then there must have been \"empty time\" out of which time arose. This is incoherent (for Kant) for the following reason: Since, necessarily, no time elapses in this pretemporal void, then there could be no alteration, and therefore nothing (including time) would ever come to be: so the antithesis is proven. Reason makes equal claim to each proof, since they are both correct, so the question of the limits of time must be regarded as meaningless. This was part of Kant\'s critical program of determining limits to science and philosophical inquiry. These contradictions are inherent in reason when it is applied to the world as it is in itself, independently of any perception of it (this has to do with the distinction between phenomena and noumena). Kant\'s goal in his critical philosophy was to identify what claims are and are not justified, and the antinomies are a particularly illustrative example of his larger project. ## Marx\'s use {#marxs_use} In the book Das Kapital, Volume I in the chapter \"The Working Day\", Karl Marx claims that capitalist production sustains \"the assertion of a right to an unlimited working day, and the assertion of a right to a limited working day, both with equal justification\". Author James Furner claims that the thesis and antithesis of this antinomy are not contradictory opposites, but rather \"consist in the assertion of rights to states of affairs that are contradictory opposites\".	2025-06-20T00:00:00
3,189	Ascending chain condition	In mathematics, the ascending chain condition (ACC) and descending chain condition (DCC) are finiteness properties satisfied by some algebraic structures, most importantly ideals in certain commutative rings. These conditions played an important role in the development of the structure theory of commutative rings in the works of David Hilbert, Emmy Noether, and Emil Artin. The conditions themselves can be stated in an abstract form, so that they make sense for any partially ordered set. This point of view is useful in abstract algebraic dimension theory due to Gabriel and Rentschler. ## Definition A partially ordered set (poset) P is said to satisfy the ascending chain condition (ACC) if no infinite strictly ascending sequence : $a_1 < a_2 < a_3 < \cdots$ of elements of P exists. Equivalently, every weakly ascending sequence : $a_1 \leq a_2 \leq a_3 \leq \cdots,$ of elements of P eventually stabilizes, meaning that there exists a positive integer n such that : $a_n = a_{n+1} = a_{n+2} = \cdots.$ Similarly, P is said to satisfy the descending chain condition (DCC) if there is no infinite strictly descending chain of elements of P. Equivalently, every weakly descending sequence : $a_1 \geq a_2 \geq a_3 \geq \cdots$ of elements of P eventually stabilizes. ### Comments - Assuming the axiom of dependent choice, the descending chain condition on (possibly infinite) poset P is equivalent to P being well-founded: every nonempty subset of P has a minimal element (also called the minimal condition or minimum condition). A totally ordered set that is well-founded is a well-ordered set. - Similarly, the ascending chain condition is equivalent to P being converse well-founded (again, assuming dependent choice): every nonempty subset of P has a maximal element (the maximal condition or maximum condition). - Every finite poset satisfies both the ascending and descending chain conditions, and thus is both well-founded and converse well-founded. ## Example Consider the ring : $\mathbb{Z} = \{\dots, -3, -2, -1, 0, 1, 2, 3, \dots\}$ of integers. Each ideal of $\mathbb{Z}$ consists of all multiples of some number $n$. For example, the ideal : $I = \{\dots, -18, -12, -6, 0, 6, 12, 18, \dots\}$ consists of all multiples of $6$. Let : $J = \{\dots, -6, -4, -2, 0, 2, 4, 6, \dots\}$ be the ideal consisting of all multiples of $2$. The ideal $I$ is contained inside the ideal $J$, since every multiple of $6$ is also a multiple of $2$. In turn, the ideal $J$ is contained in the ideal $\mathbb{Z}$, since every multiple of $2$ is a multiple of $1$. However, at this point there is no larger ideal; we have \"topped out\" at $\mathbb{Z}$. In general, if $I_1, I_2, I_3, \dots$ are ideals of $\mathbb{Z}$ such that $I_1$ is contained in $I_2$, $I_2$ is contained in $I_3$, and so on, then there is some $n$ for which all $I_n = I_{n+1} = I_{n+2} = \cdots$. That is, after some point all the ideals are equal to each other. Therefore, the ideals of $\mathbb{Z}$ satisfy the ascending chain condition, where ideals are ordered by set inclusion. Hence $\mathbb{Z}$ is a Noetherian ring.	2025-06-20T00:00:00
3,192	Adin Steinsaltz	Rabbi Adin Even-Israel Steinsaltz (עדין אבן-ישראל שטיינזלץ; 11 July 1937`{{spnd}}`{=mediawiki}7 August 2020) was an Israeli Chabad Chasidic rabbi, teacher, philosopher, social critic, author, translator and publisher. His Steinsaltz edition of the Talmud was originally published in modern Hebrew, with a running commentary to facilitate learning, and has also been translated into English, French, Russian, and Spanish. Beginning in 1989, Steinsaltz published several tractates in Hebrew and English of the Babylonian (Bavli) Talmud in an English-Hebrew edition. The first volume of a new English-Hebrew edition, the Koren Talmud Bavli, was released in May 2012, and has since been brought to completion. Steinsaltz was a recipient of the Israel Prize for Jewish Studies (1988), the President\'s Medal (2012), and the Yakir Yerushalayim prize (2017). Steinsaltz died in Jerusalem on 7 August 2020 from acute pneumonia. ## Biography Adin Steinsaltz was born in Jerusalem on 11 July 1937 to Avraham Steinsaltz and Leah (née Krokovitz). His father was a great-grandson of the first Slonimer Rebbe, Avrohom Weinberg, and was a student of Hillel Zeitlin. Avraham and Leah Steinsaltz met through Zeitlin. They immigrated to Mandatory Palestine in 1924. Avraham Steinsaltz, a devoted communist and member of Lehi, went to Spain in 1936 to fight with the International Brigades in the Spanish Civil War. Adin was born the following year. Steinsaltz became a baal teshuva during his teenage years and learned from Rabbi Shmuel Elazar Heilprin (Rosh yeshiva of Yeshivas Toras Emes Chabad). He studied mathematics, physics, and chemistry at the Hebrew University of Jerusalem, in addition to rabbinical studies at Yeshivas Tomchei Temimim in Lod and with Dov Ber Eliezrov and Shmaryahu Noach Sasonkin. Following graduation, he established several experimental schools after an unsuccessful attempt to start a neo-Hassidic community in the Negev, and, at the age of 24, became Israel\'s youngest school principal. In 1965, he founded the Israel Institute for Talmudic Publications and began his work on the Talmud, including translation into Hebrew, English, Russian, and various other languages. The Steinsaltz editions of the Talmud include translation from the original Aramaic and a comprehensive commentary. Steinsaltz completed his Hebrew edition of the entire Babylonian Talmud in November 2010, at which time Koren Publishers Jerusalem became the publisher of all of his works, including the Talmud. While not without criticism (such as by Jacob Neusner in 1998), the Steinsaltz edition is widely used throughout Israel, the United States, and the world. Steinsaltz\'s classic work on Kabbalah, The Thirteen Petalled Rose, was first published in 1980 and now appears in eight languages. In all, Steinsaltz authored some 60 books and hundreds of articles on subjects including Talmud, Jewish mysticism, Jewish philosophy, sociology, historical biography, and philosophy. Many of these works were translated into English by his close friend, Yehuda Hanegbi. His memoir-biography on the Lubavitcher Rebbe, Rabbi Menachem Mendel Schneerson, was published by Maggid Books (2014). Continuing his work as a teacher and spiritual mentor, Steinsaltz joined the original faculty of the nondenominational Pardes Institute of Jewish Studies in Jerusalem in 1972, along with David Hartman, Eliezer Schweid, Menachem Froman, Dov Berkovits, and others. He established Yeshivat Makor Chaim alongside Rabbis Menachem Froman and Shimon Gershon Rosenberg in 1984 and Yeshivat Tekoa in 1999. He also served as president of the Shefa Middle and High Schools. He has served as scholar in residence at the Woodrow Wilson International Center for Scholars in Washington, D.C., and the Institute for Advanced Study in Princeton. His honorary degrees include doctorates from Yeshiva University, Ben Gurion University of the Negev, Bar Ilan University, Brandeis University, and Florida International University. Steinsaltz was also Rosh Yeshiva of Yeshivat Hesder Tekoa. Being a follower of Rabbi Menachem Mendel Schneerson of Chabad, he went to help Jews in the Soviet Union assisting Chabad\'s shluchim (emissaries) network. In 1995, the chief rabbi of Russia, Adolf Shayevich, gave Steinzaltz the title of Duchovny Ravin (\"Spiritual Rabbi\"), a historic Russian title that indicated that he was the spiritual mentor of Russian Jewry. In this capacity, Steinsaltz travelled to Russia and the Republics`{{which\|date=November 2024}}`{=mediawiki} once each month from his home in Jerusalem. During his time in the former Soviet Union, he founded the Jewish University, both in Moscow and Saint Petersburg. The Jewish University is the first degree-granting institution of Jewish studies in the former Soviet Union. In 1991, on Schneersohn\'s advice, he changed his family name from Steinsaltz to Even-Israel, \'Stone of Israel\' in English. Schneersohn suggested the name Even Melach, \'Salt Stone\' in English, as recorded in his meeting with the Rebbe in 1990. Besides Chabad, Steinsaltz was also inspired by the teachings of Menachem Mendel of Kotzk. He was in close contact with the fifth Gerrer Rebbe, Yisrael Alter, and his brother and successor, Simcha Bunim Alter. Steinsaltz took a cautious approach to interfaith dialogue. During a visit of a delegation of Roman Catholic cardinals in Manhattan in January 2004, he said that, \"You do not have to raise over-expectations of a meeting, as it doesn\'t signify in itself a breakthrough; however, the opportunity for cardinals and rabbis to speak face to face is valuable. It\'s part of a process in which we can talk to each other in a friendly way\", and called for \"a theological dialogue that asks the tough questions, such as whether Catholicism allows for Jews to enter eternal paradise\". Steinsaltz and his wife lived in Jerusalem until his death and had three children and many grandchildren and great-grandchildren. In 2016, Steinsaltz suffered a stroke, leaving him unable to speak. His son, Rabbi Menachem (\"Meni\") Even-Israel, is the executive director of the Steinsaltz Center, Steinsaltz\'s umbrella organization located in the Nachlaot neighborhood of Jerusalem. Steinsaltz died in Jerusalem on 7 August 2020, from acute pneumonia at the Shaare Tzedek Medical Center. He was hospitalized earlier in the week with a severe lung infection. His wife Sarah survived him, together with three children and eighteen grandchildren. ## As an author {#as_an_author} Steinsaltz was a prolific author and commentator who wrote numerous books on Jewish knowledge, tradition and culture, and produced original commentaries on a huge portion of the Jewish canon: Tanakh (the Jewish bible), the Babylonian Talmud, the Mishna, the Mishneh Torah, Tanya, and Torah Or/Likutei Torah. His published works include: - Biblical Images (1984) - The Candle of God (1998) - A Dear Son to Me (2011) - The Essential Talmud (1976) - A Guide to Jewish Prayer (2000) - The Passover Haggadah (1983) - In the Beginning (1992) - My Rebbe (2014) - The Tales of Rabbi Nachman of Bratslav (1993) - On Being Free (1995) - The Miracle of the Seventh Day (2003) - Simple Words (1999) - The Strife of the Spirit (1988) - A Reference Guide to The Talmud (1989) - Talmudic Images (1997) - Learning from the Tanya (2005) - Opening the Tanya (2003) - Understanding the Tanya (2007) - Teshuvah (1982) - The Longer Shorter Way (1988) - The Seven Lights: On the Major Jewish Festivals (2000) - The Sustaining Utterance (1989) - The Thirteen Petalled Rose (1980) - We Jews (2005) - The Woman of Valor (1994) ## As a speaker {#as_a_speaker} Steinsaltz was invited to speak at the Aspen Institute for Humanistic Studies at Yale University in 1979. Prior to his stroke, he gave evening seminars in Jerusalem, which, according to Newsweek, usually lasted until 2:00 in the morning and attracted prominent politicians, such as the former Prime Minister Levi Eshkol and former Finance Minister Pinchas Sapir. ## Awards and critical reception {#awards_and_critical_reception} On 21 April 1988, Steinsaltz received the Israel Prize for Jewish Studies. On 9 February 2012, Steinsaltz was honored by Israeli President Shimon Peres with Israel\'s first President\'s Prize alongside Zubin Mehta, Uri Slonim, Henry Kissinger, Judy Feld Carr, and the Rashi Foundation.\[15\] Steinsaltz was presented with this award for his contribution to the study of Talmud, making it more accessible to Jews worldwide. Steinsaltz was also presented with the 2012 National Jewish Book Award in the category of Modern Jewish Thought & Experience by the Jewish Book Council for his commentary, translation, and notes in the Koren Babylonian Talmud. The Modern Jewish Thought & Experience award was awarded on 15 January 2013 in memory of Joy Ungerleider Mayerson by the Dorot Foundation. On 22 May 2017, Jerusalem Mayor Nir Barkat visited Steinsaltz at his home to present him with the Yakir Yerushalayim (\"Worthy Citizen of Jerusalem\") medal. This medal of achievement was awarded to Steinsaltz for his writing and translating work. On 10 June 2018, Steinsaltz was honored at a Gala Dinner at the Orient Hotel in Jerusalem for his pedagogical achievements throughout a lifetime dedicated to Jewish education. A limited-edition version of \"The Steinsaltz Humash\" was presented to the attendees of this event. ## Public reception {#public_reception} ### Academic criticism {#academic_criticism} Jacob Neusner published an attack on the Reference Guide in 1998, strongly disagreeing with several claims in the Guide. In what was an overall favorable review, Dr. Jeremy Brown notes that the Koren Talmud Bavli contains some inaccurate scientific information, such as identifying Ursa Major as a star and describing polycythemia vera as a disease causing excessive bleeding from the gums and from ordinary cuts. Aharon Feldman penned a lengthy critical review of the Steinsaltz Talmud contending that the work \"is marred by an extraordinary number of inaccuracies stemming primarily from misreadings of the sources; it fails to explain those difficult passages which the reader would expect it to explain; and it confuses him with notes which are often irrelevant, incomprehensible, and contradictory.\" Feldman says he fears that, \"An intelligent student utilizing the Steinsaltz Talmud as his personal instructor might in fact conclude that Talmud in general is not supposed to make sense.\" Furthermore, writes Feldman, the Steinsaltz Talmud gives off the impression that the Talmud is \"intellectually flabby, inconsistent, and often trivial.\" ### Haredi reaction and ban {#haredi_reaction_and_ban} Publication of the Steinsaltz Hebrew translation of the Talmud in the 1960s received endorsements from prominent rabbis including Moshe Feinstein and Ovadia Yosef. However, in 1989, when the English version appeared, Steinsaltz faced a fierce backlash from many leading rabbis in Israel such as Harav Elazar Shach, Harav Yosef Shalom Eliashiv, Harav Eliezer Waldenberg, Harav Nissim Karelitz, Harav Chaim Pinchas Scheinberg, and Harav Shmuel Wosner, who harshly condemned his work and other publications. Branding him a heretic, Rav Shach was at the forefront of a campaign which banned all his works, believing that his literary and psychological explanations of biblical characters and events rendered them heretical. He also slated his translation of the Talmud, describing it as being written in the style of a secular book causing \"any trace of holiness and faith to vanish.\" Waldenberg wrote that he was shocked to see the way in which Steinsaltz described the Patriarchs and Talmudic sages, writing that the works had the power to \"poison the souls\" of those who read them. Striking a more conciliatory tone in the controversy, however, were the Gerer Hasidim who praised his works and commended him on his willingness to amend various passages \"which could have been misconstrued.\" After the Jerusalem-based Edah Charedis limited the ban to three books, Steinsaltz publicly apologised for his error and offered to refund anyone who had bought the books. The ban nevertheless caused thousands of schools and individuals to discard the Steinsaltz Talmud, with Rabbi Avigdor Nebenzahl ordering all copies to be placed in genizah. This led to more liberal Jewish movements placing adverts in the press asking for the edition to be donated to their institutions instead. For his part, Steinsaltz countered that much of the criticism he faced was rooted in opposition to the Chabad-Lubavitch community with which he was affiliated. ### Praise While certain members of the Haredi community may have opposition to Steinsaltz\'s works, other Jewish leaders, rabbis, and authors have spoken or written about their appreciation for Steinsaltz\'s unique educational approach. Rabbi John Rosove of Temple Israel of Hollywood featured \"Opening The Tanya\", \"Learning the Tanya\", and \"Understanding the Tanya\" on his list of the top ten recommended Jewish books. These volumes are written by Rabbi Shneur Zalman of Liadi, the founder of the Chabad Lubavitch movement, and include commentary by Steinsaltz. Through reading the Tanya, readers can explore all aspects of the central text of Chabad movement. Rabbi Elie Kaunfer, a rosh yeshiva and the CEO of Mechon Hadar Yeshiva, discussed his gratitude for Steinsaltz\'s Global Day of Jewish Learning and the opportunity created by this online platform for learning and creating a deeper connection to Torah, other Jewish text, and Jews worldwide. Rabbi Pinchas Allouche, who studied under Steinsaltz, notes that Steinsaltz \"is a world scholar\" who \"revolutionized the Jewish landscape\" through his commentary, other writings, and educational organizations. In 1988, secular Israeli historian Zeev Katz compared Steinsaltz\'s importance to that of Rashi and Maimonides, two Jewish scholars of medieval times. In addition, Ilana Kurshan, an American-Israeli author, wrote that Steinsaltz\'s ability to bring \"the historical world of the Talmudic stages to life\" created an enjoyable Jewish learning experience for her when she was intensely studying Talmud.	2025-06-20T00:00:00
3,198	A. E. Housman	Alfred Edward Housman (`{{IPAc-en\|ˈ\|h\|aʊ\|s\|m\|ən}}`{=mediawiki}; 26 March 1859 -- 30 April 1936) was an English classical scholar and poet. He showed early promise as a student at the University of Oxford, but he failed his final examination in literae humaniores and took employment as a patent examiner in London in 1882. In his spare time he engaged in textual criticism of classical Greek and Latin texts, and his publications as an independent researcher earned him a high academic reputation and appointment as professor of Latin at University College London in 1892. In 1911 he became the Kennedy Professor of Latin at the University of Cambridge. Today he is regarded as one of the foremost classicists of his age and one of the greatest classical scholars of any time. His editions of Juvenal, Manilius, and Lucan are still considered authoritative. In 1896, Housman published A Shropshire Lad, a cycle of poems marked by the author\'s pessimism and preoccupation with early death, which gradually acquired a wide readership and appealed particularly to a younger audience during World War I. Another collection, entitled Last Poems, appeared in 1922. Housman\'s poetry became popular for musical settings. Following his death, further poems from his notebooks were published by his brother Laurence. ## Early life {#early_life} thumb\\|upright=1.3\\|Valley House, Housman\'s birthplace thumb\\|upright=1.3\\|The site of the 17th-century Fockbury House (later known as The Clock House). Home of Housman from 1873 to 1878 thumb\\|upright=1.3\\|Home of Housman from 1860 to 1873 and again from 1878 to 1882. His younger brother Laurence was born here in 1865. The eldest of seven children, Housman was born at Valley House in Fockbury, a hamlet on the outskirts of Bromsgrove in Worcestershire, to Sarah Jane (née Williams, married 17 June 1858 in Woodchester, Gloucester) and Edward Housman (whose family came from Lancaster), and was baptised on 24 April 1859 at Christ Church, in Catshill. His mother died on his twelfth birthday, and his father, a country solicitor, then married an elder cousin, Lucy, in 1873. Two of his siblings became prominent writers, sister Clemence Housman and brother Laurence Housman. Housman was educated at King Edward\'s School in Birmingham and later Bromsgrove School, where he revealed his academic promise and won prizes for his poems. In 1877, he won an open scholarship to St John\'s College, Oxford, and went there to study classics. Although introverted by nature, Housman formed strong friendships with two roommates, Moses John Jackson (1858--1923) and A. W. Pollard. Though Housman obtained a first in classical Moderations in 1879, his dedication to textual analysis led him to neglect the ancient history and philosophy that formed part of the Greats curriculum. Accordingly, he failed his Finals and had to return humiliated in Michaelmas term to resit the exam and at least gain a lower-level pass degree. Though some attribute Housman\'s unexpected performance in his exams directly to his unrequited feelings for Jackson, most biographers adduce more obvious causes. Housman was indifferent to philosophy and overconfident in his exceptional gifts, and he spent too much time with his friends. He may also have been distracted by news of his father\'s desperate illness. After Oxford, Jackson went to work as a clerk in the Patent Office in London and he also arranged a job there for Housman. The two shared a flat at 82 Talbot Road, Bayswater, with Jackson\'s brother Adalbert until 1885, when Housman moved to lodgings of his own, probably after Jackson responded to a declaration of love by telling Housman that he could not reciprocate his feelings. Two years later, Jackson moved to India, placing more distance between himself and Housman. When he returned briefly to England in 1889 to marry, Housman was not invited to the wedding and knew nothing about it until the couple had left the country. Adalbert Jackson died in 1892 and Housman commemorated him in a poem published as \"XLII -- A.J.J.\" of More Poems (1936). Meanwhile, Housman pursued his classical studies independently, and published scholarly articles on Horace, Propertius, Ovid, Aeschylus, Euripides and Sophocles. He also completed an edition of Propertius, which however was rejected by both Oxford University Press and Macmillan in 1885, and was destroyed after his death. He gradually acquired such a high reputation that in 1892 he was offered and accepted the professorship of Latin at University College London (UCL). When, during his tenure, an immensely rare Coverdale Bible of 1535 was discovered in the UCL library and presented to the Library Committee, Housman (who had become an atheist while at Oxford) remarked that it would be better to sell it to \"buy some really useful books with the proceeds\". ## Later life {#later_life} Although Housman\'s early work and his responsibilities as a professor included both Latin and Greek, he began to specialise in Latin poetry. When asked later why he had stopped writing about Greek verse, he responded, \"I found that I could not attain to excellence in both.\" In 1911 he took the Kennedy Professorship of Latin at Trinity College, Cambridge, where he remained for the rest of his life. Between 1903 and 1930, Housman published his critical edition of Manilius\'s Astronomicon in five volumes. He also edited Juvenal (1905) and Lucan (1926). G. P. Goold, Classics Professor at University College, wrote of his predecessor\'s accomplishments that \"the legacy of Housman\'s scholarship is a thing of permanent value; and that value consists less in obvious results, the establishment of general propositions about Latin and the removal of scribal mistakes, than in the shining example he provides of a wonderful mind at work ... He was and may remain the last great textual critic\". In the eyes of Harry Eyres, however, Housman was \"famously dry\" as a professor, and his influence led to a scholarly style in the study of literature and poetry that was philological and without emotion. left\\|thumb\\|upright=1.3\\|Housman\'s grave marker Many colleagues were unnerved by Housman\'s scathing attacks on those he thought guilty of shoddy scholarship. In his paper \"The Application of Thought to Textual Criticism\" (1921) he wrote: \"A textual critic engaged upon his business is not at all like Newton investigating the motion of the planets: he is much more like a dog hunting for fleas\". He declared many of his contemporary scholars to be stupid, lazy, vain, or all three, saying: \"Knowledge is good, method is good, but one thing beyond all others is necessary; and that is to have a head, not a pumpkin, on your shoulders, and brains, not pudding, in your head\". His younger colleague, A. S. F. Gow, quoted examples of these attacks, noting that they \"were often savage in the extreme\". Gow also related how Housman intimidated students, sometimes reducing the women to tears. According to Gow, Housman could never remember the names of female students, maintaining that \"had he burdened his memory by the distinction between Miss Jones and Miss Robinson, he might have forgotten that between the second and fourth declension\". Among the more notable students at his Cambridge lectures was Enoch Powell, one of whose own Classical emendations was later complimented by Housman. thumb\\|upright=1.6\\|Housman\'s grave at St Laurence\'s Church in Ludlow In his private life, Housman enjoyed country walks, gastronomy, air travel and making frequent visits to France, where he read \"books which were banned in Britain as pornographic\" but he struck A. C. Benson, a fellow don, as being \"descended from a long line of maiden aunts\". His feelings about his poetry were ambivalent and he certainly treated it as secondary to his scholarship. He did not speak in public about his poems until 1933, when he gave a lecture \"The Name and Nature of Poetry\", arguing there that poetry should appeal to emotions rather than to the intellect. Housman died, aged 77, in Cambridge. His ashes are buried just outside St Laurence\'s Church, Ludlow. A cherry tree was planted there in his memory (see A Shropshire Lad II) and replaced by the Housman Society in 2003 with a new cherry tree nearby. ## Poetry ### A Shropshire Lad {#a_shropshire_lad} During his years in London, Housman completed A Shropshire Lad, a cycle of 63 poems. After one publisher had turned it down, he helped subsidise its publication in 1896. At first selling slowly, it rapidly became a lasting success. Its appeal to English musicians had helped to make it widely known before World War I, when its themes struck a powerful chord with English readers. The book has been in print continuously since May 1896. The poems are marked by pessimism and preoccupation with death, without religious consolation (Housman had become an atheist while still an undergraduate). Housman wrote many of them while living in Highgate, London, before ever visiting Shropshire, which he presented in an idealised pastoral light as his \'land of lost content\'. Housman himself acknowledged that \"No doubt I have been unconsciously influenced by the Greeks and Latins, but \[the\] chief sources of which I am conscious are Shakespeare\'s songs, the Scottish Border ballads, and Heine\". ### Later collections {#later_collections} Housman began collecting a new set of poems after the First World War. His early work was an influence on many British poets who became famous by their writing about the war, and he wrote several poems as occasional verse to commemorate the war dead. This included his Epitaph on an Army of Mercenaries, honouring the British Expeditionary Force, an elite but small force of professional soldiers sent to Belgium at the start of the war. In the early 1920s, when Moses Jackson was dying in Canada, Housman wanted to assemble his best unpublished poems so that Jackson could read them before his death. These later poems, mostly written before 1910, show a greater variety of subject and form than those in A Shropshire Lad but lack its consistency. He published his new collection as Last Poems (1922), feeling that his inspiration was exhausted and that he should not publish more in his lifetime. After Housman\'s death in 1936, his brother, Laurence published further poems in More Poems (1936), A. E .H.: Some Poems, Some Letters and a Personal Memoir by his Brother (1937), and Collected Poems (1939). A. E. H. includes humorous verse such as a parody of Longfellow\'s poem Excelsior. Housman also wrote a parodic Fragment of a Greek Tragedy, in English, first published in 1883 in The Bromsgrovian, the magazine of his old school, and frequently reprinted. John Sparrow quoted a letter written late in Housman\'s life that described the genesis of his poems: `{{Blockquote \| Poetry was for him …'a morbid secretion', as the pearl is for the oyster. The desire, or the need, did not come upon him often, and it came usually when he was feeling ill or depressed; then whole lines and stanzas would present themselves to him without any effort, or any consciousness of composition on his part. Sometimes they wanted a little alteration, sometimes none; sometimes the lines needed in order to make a complete poem would come later, spontaneously or with 'a little coaxing'; sometimes he had to sit down and finish the poem with his head. That... was a long and laborious process.<ref Name="Sparrow" />}}`{=mediawiki} Sparrow himself adds, \"How difficult it is to achieve a satisfactory analysis may be judged by considering the last poem in A Shropshire Lad. Of its four stanzas, Housman tells us that two were \'given\' him ready made; one was coaxed forth from his subconsciousness an hour or two later; the remaining one took months of conscious composition. No one can tell for certain which was which.\" ### De Amicitia (Of Friendship) {#de_amicitia_of_friendship} In 1942, Laurence Housman also deposited an essay entitled \"A. E. Housman\'s \'De Amicitia\'\" in the British Library, with the proviso that it was not to be published for 25 years. The essay discussed A. E. Housman\'s homosexuality and his love for Moses Jackson. Despite the conservative nature of the times and his own caution in public life, Housman was quite open in his poetry, and especially in A Shropshire Lad, about his deeper sympathies. Poem XXX of that sequence, for instance, speaks of how \"Fear contended with desire\": \"Others, I am not the first, / Have willed more mischief than they durst\". In More Poems, he buries his love for Moses Jackson in the very act of commemorating it, as his feelings of love are not reciprocated and must be carried unfulfilled to the grave: thumb\\|upright=0.9\\|Moses Jackson (1858--1923) as an undergraduate c. 1880 `{{poemquote\| To put the world between us We parted, stiff and dry; "Good-bye," said you, "forget me." "I will, no fear," said I. If here, where clover whitens The dead man's knoll, you pass, And no tall flower to meet you Starts in the trefoiled grass, Halt by the headstone naming The heart no longer stirred, And say the lad that loved you Was one that kept his word.<ref>{{cite book \|last=Housman \|first=A. E. \|author-link=A. E. Housman \|title=More Poems \|date=1936 \|publisher=A. A. Knopf \|location=New York \|pages=[https://archive.org/details/morepoems0000hous/page/44 44]–45 \|url=https://archive.org/details/morepoems0000hous\|url-access=registration }}</ref>}}`{=mediawiki} His poem \"Oh who is that young sinner with the handcuffs on his wrists?\", written after the trial of Oscar Wilde, addressed more general attitudes towards homosexuals. In the poem the prisoner is suffering \"for the colour of his hair\", a natural quality that, in a coded reference to homosexuality, is reviled as \"nameless and abominable\" (recalling the legal phrase peccatum illud horribile, inter Christianos non nominandum, \"that horrible sin, not to be named amongst Christians\"). ## Musical settings {#musical_settings} Housman\'s poetry, especially A Shropshire Lad, was set to music by many British, and in particular English, composers in the first half of the 20th century. The national, pastoral and traditional elements of his style resonated with similar trends in English music. In 1904, the cycle A Shropshire Lad was set by Arthur Somervell, who in 1898 had begun to develop the concept of the English song-cycle in his version of Tennyson\'s \"Maud\". Stephen Banfield believes it was acquaintance with Somervell\'s cycle that led other composers to set Housman: Ralph Vaughan Williams is likely to have attended the first performance at the Aeolian Hall on 3 February 1905. His well-known cycle of six songs On Wenlock Edge, for string quartet, tenor and piano, was published in 1909. Between 1909 and 1911, George Butterworth produced settings in two collections, Six Songs from A Shropshire Lad and Bredon Hill and Other Songs. He also wrote the orchestral tone poem A Shropshire Lad, first performed at Leeds Festival in 1912. Ivor Gurney was another composer who made renowned settings of Housman\'s poems. Towards the end of World War I, he was working on his cycle Ludlow and Teme, for voice and string quartet (published in 1919), and went on to compose the eight-song cycle The Western Playland in 1921. One more who set Housman songs during this period was John Ireland in the song cycle, The Land of Lost Content (1920`{{ndash}}`{=mediawiki}21). Charles Wilfred Orr produced 24 Housman settings in songs and song cycles composed from the 1920s into the 1950s. Even composers not directly associated with the \'pastoral\' tradition, such as Arnold Bax, Lennox Berkeley and Arthur Bliss, were attracted to Housman\'s poetry. Housman\'s attitude to musical interpretations of his poetry, and indeed to music in general, was either indifference or torment. He told his friend Percy Withers that he knew nothing of music and it meant nothing to him. Withers once played him a record of the Vaughan Williams setting, but realised he had made a mistake when he saw the look of disgust on the poet\'s face. Nevertheless, by 1976, a catalogue listed 400 musical settings of Housman\'s poems. As of 2024, Lieder Net Archive records 678 settings of 188 texts. ## Commemorations The earliest commemoration of Housman was in the chapel of Trinity College in Cambridge, where there is a memorial brass on the south wall. The Latin inscription was composed by his colleague there, A. S. F. Gow, who was also the author of a biographical and bibliographical sketch published immediately following his death. Translated into English, the memorial reads: `{{Blockquote\|This inscription commemorates Alfred Edward Housman, who was for twenty-five years Kennedy Professor of Latin and Fellow of the College. Following in [[Richard Bentley\|Bentley]]'s footsteps he corrected the transmitted text of the Latin poets with so keen an intelligence and so ample a stock of learning, and chastised the sloth of editors with such sharp mockery, that he takes his place as the virtual second founder of these studies. He was also a poet who, with a slender sheaf of verses, claimed for himself a secure place on our Helicon. He died on 30 April 1936 at the age of seventy-six.<ref>In its original Latin the plaque reads: {{smaller\|HOC TITVLO COMMEMORATVR / ALFRED EDWARD HOUSMAN / PER XXV ANNOS LINGVAE LATINAE PROFESSOR KENNEDIANVS / ET HVIVS COLLEGII SOCIVS / QVI BENTLEII INSISTENS VESTIGIIS / TEXTVM TRADITVM POETARVM LATINORVM / TANTO INGENII ACVMINE TANTIS DOCTRINAE COPIIS / EDITORVM SOCORDIAM / TAM ACRI CAVILLATIONE CASTIGAVIT / VT HORVM STVDIORVM PAENE REFORMATOR EXSTITERIT / IDEM POETA / TENVI CARMINVM FASCICVLO / SEDEM SIBI TVTAM IN HELICONE NOSTRO VINDICAVIT / OBIIT PRID.KAL.MAI./ A.S.MDCCCCXXXVI AETATIS SVAE LXXVII}}</ref>}}`{=mediawiki} thumb\\|upright=1.05\\|Housman statue in Bromsgrove From 1947, University College London\'s academic common room was dedicated to his memory as the Housman Room. Blue plaques followed later elsewhere, the first being on Byron Cottage in Highgate in 1969, recording the fact that A Shropshire Lad was written there. More followed, placed on his Worcestershire birthplace, his homes and school in Bromsgrove. The latter were encouraged by the Housman Society, which was founded in the town in 1973. Another initiative was the statue in Bromsgrove High Street, showing the poet striding with walking stick in hand. The work of local sculptor Kenneth Potts, it was unveiled on 22 March 1985. The blue plaques in Worcestershire were set up on the centenary of A Shropshire Lad in 1996. In September of the same year, a memorial window lozenge was dedicated at Poets\' Corner in Westminster Abbey The following year saw the première of Tom Stoppard\'s play The Invention of Love, whose subject is the relationship between Housman and Moses Jackson. As the 150th anniversary of his birth approached, London University inaugurated its Housman lectures on classical subjects in 2005, initially given every second year then annually after 2011. The anniversary itself in 2009 saw the publication of a new edition of A Shropshire Lad, including pictures from across Shropshire taken by local photographer Gareth Thomas. Among other events, there were performances of Vaughan Williams\'s On Wenlock Edge and Ivor Gurney\'s Ludlow and Teme at St Laurence\'s Church in Ludlow. ## Works ### Poetry collections {#poetry_collections} - A Shropshire Lad (1896) - Last Poems (1922, Henry Holt & Company) - A Shropshire Lad: Authorized Edition (1924, Henry Holt & Company) - More Poems (1936, Barclays) - Collected Poems (1940, Henry Holt & Company) - Collected Poems (1939); the poems included in this volume but not the three above are known as Additional Poems. The Penguin edition of 1956 includes an introduction by John Sparrow. - Manuscript Poems: Eight Hundred Lines of Hitherto Uncollected Verse from the Author\'s Notebooks, ed. Tom Burns Haber (1955) - A. E. Housman: Collected Poems and Selected Prose, ed. Christopher Ricks (1988, Allen Lane) - Unkind to Unicorns: Selected Comic Verse, ed. J. Roy Birch (1995; 2nd ed. 1999) - The Poems of A. E. Housman, ed. Archie Burnett (1997) - A Shropshire Lad and Other Poems (2010, Penguin Classics) ### Classical scholarship {#classical_scholarship} - P. Ovidi Nasonis Ibis (1894. In J. P. Postgate\'s \"Corpus Poetarum Latinorum\") - M. Manilii Astronomica (1903--1930; 2nd ed. 1937; 5 vols.) - D. Iunii Iuuenalis Saturae: editorum in usum edidit (1905; 2nd ed. 1931) - M. Annaei Lucani, Belli Ciuilis Libri Decem: editorum in usum edidit (1926; 2nd ed. 1927) - The Classical Papers of A. E. Housman, ed. J. Diggle and F. R. D. Goodyear (1972; 3 vols.) - \"Housman\'s Latin Inscriptions\", William White, The Classical Journal (1955) 159--66 ### Published lectures {#published_lectures} These lectures are listed by date of delivery, with date of first publication given separately if different. - Introductory Lecture (1892) - \"Swinburne\" (1910; published 1969) - Cambridge Inaugural Lecture (1911; published 1969 as \"The Confines of Criticism\") - \"The Application of Thought to Textual Criticism\" (1921; published 1922) - \"The Name and Nature of Poetry\" (1933) ### Prose collections {#prose_collections} Selected Prose, edited by John Carter, Cambridge University Press, 1961 ### Collected letters {#collected_letters} - The Letters of A. E. Housman, ed. Henry Maas (1971) - The Letters of A. E. Housman, ed. Archie Burnett (2007)	2025-06-20T00:00:00
3,203	Achduart	Achduart (Gaelic: *Achadh Dhubhaird*) is a coastal hamlet in Coigach, Wester Ross in northwestern Scotland, now within the Highland council area. It is situated about 4 km southeast of the village of Achiltibuie, at the end of a minor road. A footpath continues on to the hamlet of Culnacraig, then along the coast past Ben More Coigach to Strathcanaird. Achduart has accommodation facilities for tourists, who come for its proximity to the sea and its seclusion and remoteness. There is a hostel in Acheninver, a short distance to the north, formerly run by the Scottish Youth Hostels Association. The name of Achduart comes from the Gaelic for \"the field at the black headland\". Achduart was part of the Estate of Coigach, Lochbroom, belonging to the Countess of Cromartie. The dominant geographical feature in the area is Cairn Conmheall, which rises to 541 metres. ## Notable people {#notable_people} - Kenny John Macleod -fiddler	2025-06-20T00:00:00
3,204	Achiltibuie	Achiltibuie (`{{IPAc-en\|ˌ\|æ\|x\|ᵻ\|l\|t\|ᵻ\|ˈ\|b\|uː\|i}}`{=mediawiki}; \'\'\'Achd Ille Bhuidhe\'\'\' or Field of the yellow-haired boy) is a long linear village in Ross and Cromarty, Highland, on the Coigach coast of northwestern Scotland, overlooking Badentarbet Bay to the west. Loch Broom and the Summer Isles lie to the south. Located 10 miles (16 km) northwest of Ullapool as the crow flies. Achiltibuie is the central community of a series of townships and communities stretching from Culnacraig, through Badenscallie and Polglass (where the community hall, the primary school and the Piping School Cafe are located), Polbain, and Reiff to Achnahaird. ## History The first post office in the village opened on 28 July 1884. ### Smokehouse For a time the Summer Isles Smokehouse attracted visitors. In 2013 the community had hopes to re-establish the business. ### Hydroponicum The Hydroponicum, a facility for growing fresh fruit and vegetables indoors using hydroponics, was built in the village in the 1980s by Robert Irvine, then owner of the Summer Isles Hotel. The Hydroponicum was known for growing exotic fruit such as bananas all year round. It attracted up to 10,000 visitors a year until it was sold in 2007 to a company based in the Isle of Man. New greenhouses have since been built apart from the original hydroponicum buildings, and the new owners continue to grow fruit and vegetables for local businesses and residents. A community buyout attempt in 2011 by the Coigach Community Development Company fell through when the site\'s sellers pulled out. The building has now been demolished. Some of the former staff of the Hydroponicum run a small-scale activity known as The Achiltibuie Garden, situated nearby. ## Notable residents {#notable_residents} - Tom Longstaff (1875--1964), mountaineer. - Lucy Irvine (b. 1956), writer, lived very briefly in the Summer Isles Hotel with her father, who owned it and the Hydroponicum. ## Notable recent achievements {#notable_recent_achievements} \'Coigach Community Rowing\' the crew members of which coastal rowing club are all local, won the World St. Ayles Skiff Rowing Championships in July 2013 and a mixed crew from the club won the Alan Spong Trophy for 1st Mixed crew 4-oar rowing at the Thames Great River Race in September 2013. Coigach Community Rowing hand-built their two St Ayles rowing skiffs, the \'Coigach Lass\' and the \'Lily\~Rose\' and race under the auspices of the Scottish Coastal Rowing Association, which is the governing body of St Ayles class coastal rowing around the world. The Brochs of Coigach designed by SBA Architects Ltd were shortlisted in 2011 for the RIAS Andrew Doolan Best Building in Scotland Award. They are two unique buildings landscaped into a hillside. They were Regional Finalist of the Civic Trust Awards 2013. In 2015, they were highly commended in the inaugural Scottish Rural Awards. ## Cultural connections {#cultural_connections} The Roman epic movie The Eagle, based on the 1954 novel The Eagle of the Ninth by Rosemary Sutcliff, was filmed on location in Achiltibuie for a week in October 2009. The main location was Fox Point, Old Dornie. The Pictish village which was constructed at Fox Point was used on most days of the filming. Other sites included Achnahaird beach where a horse chase was filmed and Loch Lurgainn. The village and its residents featured in The Wee Mad Road (2008) by Jack and Barbara Maloney.	2025-06-20T00:00:00
3,209	Mexican tetra	The Mexican tetra (*Astyanax mexicanus), also known as the blind cave fish, blind cave characin* or the blind cave tetra, is a freshwater fish in the Characidae family (tetras and relatives) of the order Characiformes. The type species of its genus, it is native to the Nearctic realm, originating in the lower Rio Grande, and the Neueces and Pecos Rivers in Texas, into the Central Plateau and eastern states of Mexico. Maturing at a total length of about 12 cm, the Mexican tetra is of typical characin form, albeit with silvery, unremarkable scalation, likely an evolutionary adaptation to its natural environment. By comparison, the species\' blind \"cave\" form has scales which evolved a pale, pinkish-white color, somewhat resembling an albino, as it inhabits pitch-black caverns and subterranean streams and has no need for a colorful appearance (i.e. for attracting mates). Likewise, the blind cave tetra has fully \"devolved\" (lost) the use of its eyes by living in an environment completely devoid of natural light, with only empty sockets in their place. The blind tetra instead has sensory organs along its body, as well as a heightened nervous system (and senses of smell and touch), and can immediately detect where objects or other animals are located by slight changes in the surrounding water pressure, a process vaguely similar to echolocation---another adaptation known from cave-dwelling, as well as aquatic, species, such as the bats and cetaceans. The Mexican tetra\'s blind variant has experienced a steady surge in popularity among modern aquarists. A. mexicanus is a peaceful, sociable schooling species, like most tetras, that spends most of its time in midlevel waters above the rocky and sandy bottoms of pools, and backwaters of creeks and streams. Coming from an environment somewhere between subtropical climate, it prefers water with 6.5--8 pH, a hardness of up to 30 dGH, and a temperature range of 20 to. In the winter, some populations migrate to warmer waters. The species\' natural diet consists largely of crustaceans, annelids and arthropods and their larvae, including both aquatic insects, such as water beetles, and those that land on or fall in the water, like flies or arachnids. It will also supplement its diet with algae or aquatic vegetation; in captivity, it is largely omnivorous, often doing well on a variety of foods such as frozen/thawed or live cultured blackworms, bloodworms, brine shrimp, daphnia, and mysis shrimp, among other commercially available fish foods. The Mexican tetra has been treated as a subspecies of A. fasciatus, though this is not widely accepted. Additionally, the hypogean blind cave form is sometimes recognized as a separate species, A. jordani, but this directly contradicts the phylogenetic evidence. ## Blind cave form {#blind_cave_form} A. mexicanus is famous for its blind cave form, which is known by such names as blind cave tetra, blind tetra (leading to easy confusion with the Brazilian Stygichthys typhlops), blind cave characin and blind cavefish. Depending on the exact population, cave forms can have degenerated sight or have total loss of sight and even their eyes, due to down-regulation of the protein αA-crystallin and consequent lens cell death. Despite losing their eyes, cavefish cells respond to light and show an endogenous circadian rhythm. During the start of development, larvae still exhibit a shadow response which is controlled by the pineal eye. The fish in the Pachón caves have lost their eyes completely whilst the fish from the Micos cave only have limited sight. Cave fish and surface fish are able to produce fertile offspring. These fish can still, however, find their way around by means of their lateral lines, which are highly sensitive to fluctuating water pressure. Blindness in A. mexicanus induces a disruption of early neuromast patterning, which further causes asymmetries in cranial bone structure. One such asymmetry is a bend in the dorsal region of their skull, which is propounded to increase water flow to the opposite side of the face, functionally enhancing sensory input and spatial mapping in the dark waters of caves. Scientists suggest that gene cystathionine beta synthase-a mutation restricts blood flow to cavefish eyes during a critical stage of growth so the eyes are covered by skin. Currently, about 30 cave populations are known, dispersed over three geographically distinct areas in a karst region of San Luis Potosí and far southern Tamaulipas, northeastern Mexico. Among the various cave population are at least three with only full cave forms (blind and without pigment), at least eleven with cave, \"normal\" and intermediate forms, and at least one with both cave and \"normal\" forms but no intermediates. Studies suggest at least two distinct genetic lineages occur among the blind populations, and the current distribution of populations arose by at least five independent invasions. Furthermore, cave populations have a very recent origin (\< 20,000 years) in which blindness or reduced vision evolved convergently after surface ancestors populated several caves independently at different times. This recent origin suggests that the phenotypic changes in cavefish populations, namely eye degeneration, arose as a result of the high fixation of genetic variants present in surface fish populations in a short period of time. The eyed and eyeless forms of A. mexicanus, being members of the same species, are closely related and can interbreed making this species an excellent model organism for examining convergent and parallel evolution, regressive evolution in cave animals, and the genetic basis of regressive traits. This, combined with the ease of maintaining the species in captivity, has made it the most studied cavefish and likely also the most studied cave organism overall. The blind and colorless cave form of A. mexicanus is sometimes recognized as a separate species, A. jordani, but this leaves the remaining A. mexicanus as a paraphyletic species and A. jordani as polyphyletic. The Cueva Chica Cave in the southern part of the Sierra del Abra system is the type locality for A. jordani. Other blind populations were initially also recognized as separate species, including antrobius described in 1946 from the Pachón Cave and hubbsi described in 1947 from the Los Sabinos Cave (both subsequently merged into jordani/mexicanus). The most divergent cave population is the one in Los Sabinos. Another cave-adapted population of Astyanax, varying from blind and depigmented to individuals showing intermediate features, is known from the Granadas Cave, part of the Balsas River drainage in Guerrero, southern Mexico, but it is a part of A. aeneus (itself sometimes included in A. mexicanus). ### Evolution research {#evolution_research} The surface and cave forms of the Mexican tetra have proven powerful subjects for scientists studying evolution. When the surface-dwelling ancestors of current cave populations entered the subterranean environment, the change in ecological conditions rendered their phenotype---which included many biological functions dependent on the presence of light---subject to natural selection and genetic drift. One of the most striking changes to evolve was the loss of eyes. This is referred to as a \"regressive trait\" because the surface fish that originally colonized caves possessed eyes. In addition to regressive traits, cave forms evolved \"constructive traits\". In contrast to regressive traits, the purpose or benefit of constructive traits is generally accepted. Active research focuses on the mechanisms driving the evolution of regressive traits, such as the loss of eyes, in A. mexicanus. Recent studies have produced evidence that the mechanism may be direct selection, or indirect selection through antagonistic pleiotropy, rather than genetic drift and neutral mutation, the traditionally favored hypothesis for regressive evolution. Pleiotropy is hypothesized to be important in cave fish because there are genes that might be selected for one trait and automatically cause another trait to be selected for it if it is governed by the same gene. As selective pressure on one trait can coordinate change in others, pleiotropy could explain why independent adaptation to the cave environment has been observed in multiple populations of the species. One example is the relationship between taste bud amplification and eye loss controlled by sonic hedgehog expression (Shh) in cave fish. It has been shown that with an over expression of Shh there is an increased number of taste buds and reduced eye development. It is hypothesized that since caves are food and nutrient limited, having an increased amount of taste buds is important and may be under strong selection while at the same time causing evolution of eye loss. The blind form of the Mexican tetra is different from the surface-dwelling form in a number of ways, including having unpigmented skin, having a better olfactory sense by having taste buds all over its head, and by being able to store four times more energy as fat, allowing it to deal with irregular food supplies more effectively. Darwin said of sightless fish:`{{Blockquote\|By the time that an animal had reached, after numberless generations, the deepest recesses, disuse will on this view have more or less perfectly obliterated its eyes, and natural selection will often have effected other changes, such as an increase in the length of antennae or palpi, as compensation for blindness.\|Charles Darwin\|''[[On the Origin of Species\|The Origin of Species]]'' (1859)}}`{=mediawiki} Modern genetics has made clear that the lack of use does not, in itself, necessitate a feature\'s disappearance. In this context, the positive genetic benefits have to be considered, i.e., what advantages are obtained by cave-dwelling tetras by losing their eyes? Possible explanations include: - Not developing eyes allows the individual more energy for growth but not egg production. However the species does use other methods to locate food and detect danger, which also consume energy that would be conserved if it had eyes or transparent eyelids. - There remains less chance of accidental damage and infection, since the previously useless and exposed organ is sealed with a flap of protective skin. It is unknown why this species did not develop transparent skin or eyelids instead, as some species of reptiles did. - The lack of eyes disables the \"body clock\", which is controlled by periods of light and dark, conserving energy. However sunlight does have minimal impact on the \"body clock\" in caves. It is important to note that even if natural selection is positively acting to reduce eye growth drift is still present. Another likely explanation for the loss of its eyes is that of selective neutrality and genetic drift; in the dark environment of the cave, the eyes are neither advantageous nor disadvantageous and thus any genetic factors that might impair the eyes (or their development) can take hold with no consequence on the individual or species. Because there is no selection pressure for sight in this environment, any number of genetic abnormalities that give rise to the damage or loss of eyes could proliferate among the population with no effect on the fitness of the population. Among some creationists, the cave tetra is seen as evidence \'against\' evolution. One argument claims this is an instance of \"devolution\"---showing an evolutionary trend of decreasing complexity. But evolution is a non-directional process, and while increased complexity is a common effect, there is no reason why evolution cannot tend towards simplicity if that makes an organism better suited to its environment. Inhibition of the HSP90 protein has a dramatic effect in the development of the blind tetra. ### In the aquarium {#in_the_aquarium} The blind cave tetras seen in the aquarium trade are all based on stock collected in the Cueva Chica Cave in the southern part of the Sierra del Abra system in 1936. These were sent to an aquarium company in Texas, who soon started to distribute them to aquarists. Since then, these have been selectively bred for their troglomorphic traits. Today large numbers are bred at commercial facilities, especially in Asia. The blind cave tetra is a hardy species. Their lack of sight does not hinder their ability to get food. They prefer subdued lighting with a rocky substrate, like gravel, mimicking their natural environment. They become semi-aggressive as they age, and are by nature schooling fish. Experiments have shown that keeping these fish in bright aquarium set-ups has no effect on the development of the skin flap that forms over their eyes as they grow.	2025-06-20T00:00:00
3,211	Atom probe	The atom probe was introduced at the [14th Field Emission Symposium in 1967](http://www.fieldemission.org/article.php?id=proceeding) by Erwin Wilhelm Müller and J. A. Panitz. It combined a field ion microscope with a mass spectrometer having a single particle detection capability and, for the first time, an instrument could "\... determine the nature of one single atom seen on a metal surface and selected from neighboring atoms at the discretion of the observer". Atom probes are unlike conventional optical or electron microscopes, in that the magnification effect comes from the magnification provided by a highly curved electric field, rather than by the manipulation of radiation paths. The method is destructive in nature removing ions from a sample surface in order to image and identify them, generating magnifications sufficient to observe individual atoms as they are removed from the sample surface. Through coupling of this magnification method with time of flight mass spectrometry, ions evaporated by application of electric pulses can have their mass-to-charge ratio computed. Through successive evaporation of material, layers of atoms are removed from a specimen, allowing for probing not only of the surface, but also through the material itself. Computer methods are used to rebuild a three-dimensional view of the sample, prior to it being evaporated, providing atomic scale information on the structure of a sample, as well as providing the type atomic species information. The instrument allows the three-dimensional reconstruction of up to billions of atoms from a sharp tip (corresponding to specimen volumes of 10,000-10,000,000 nm^3^). ## Overview Atom probe samples are shaped to implicitly provide a highly curved electric potential to induce the resultant magnification, as opposed to direct use of lensing, such as via magnetic lenses. Furthermore, in normal operation (as opposed to a field ionization modes) the atom probe does not utilize a secondary source to probe the sample. Rather, the sample is evaporated in a controlled manner (field evaporation) and the evaporated ions are impacted onto a detector, which is typically 10 to 100 cm away. The samples are required to have a needle geometry and are produced by similar techniques as TEM sample preparation electropolishing, or focused ion beam methods. Since 2006, commercial systems with laser pulsing have become available and this has expanded applications from metallic only specimens into semiconducting, insulating such as ceramics, and even geological materials. Preparation is done, often by hand, to manufacture a tip radius sufficient to induce a high electric field, with radii on the order of 100 nm. To conduct an atom probe experiment a very sharp needle shaped specimen is placed in an ultra high vacuum chamber. After introduction into the vacuum system, the sample is reduced to cryogenic temperatures (typically 20-100 K) and manipulated such that the needle\'s point is aimed towards an ion detector. A high voltage is applied to the specimen, and either a laser pulse is applied to the specimen or a voltage pulse (typically 1-2 kV) with pulse repetition rates in the hundreds of kilohertz range is applied to a counter electrode. The application of the pulse to the sample allows for individual atoms at the sample surface to be ejected as an ion from the sample surface at a known time. Typically the pulse amplitude and the high voltage on the specimen are computer controlled to encourage only one atom to ionize at a time, but multiple ionizations are possible. The delay between application of the pulse and detection of the ion(s) at the detector allow for the computation of a mass-to-charge ratio. Whilst the uncertainty in the atomic mass computed by time-of-flight methods in atom probe is sufficiently small to allow for detection of individual isotopes within a material this uncertainty may still, in some cases, confound definitive identification of atomic species. Effects such as superposition of differing ions with multiple electrons removed, or through the presence of complex species formation during evaporation may cause two or more species to have sufficiently close time-of-flights to make definitive identification impossible. ## History ### Field ion microscopy {#field_ion_microscopy} Field ion microscopy is a modification of field emission microscopy where a stream of tunneling electrons is emitted from the apex of a sharp needle-like tip cathode when subjected to a sufficiently high electric field (\~3-6 V/nm). The needle is oriented towards a phosphor screen to create a projected image of the work function at the tip apex. The image resolution is limited to (2-2.5 nm), due to quantum mechanical effects and lateral variations in the electron velocity. In field ion microscopy, the tip is cooled by a cryogen and its polarity is reversed. When an imaging gas (usually hydrogen or helium) is introduced at low pressures (\< 0.1 Pascal) gas ions in the high electric field at the tip apex are field ionized and produce a projected image of protruding atoms at the tip apex. The image resolution is determined primarily by the temperature of the tip but even at 78 Kelvin atomic resolution is achieved. ### 10-cm Atom Probe {#cm_atom_probe} The 10-cm Atom Probe, invented in 1973 by J. A. Panitz was a "new and simple atom probe which permits rapid, in depth species identification or the more usual atom-by atom analysis provided by its predecessors \... in an instrument having a volume of less than two liters in which tip movement is unnecessary and the problems of evaporation pulse stability and alignment common to previous designs have been eliminated." This was accomplished by combining a time of flight (TOF) mass spectrometer with a proximity focussed, dual channel plate detector, an 11.8 cm drift region and a 38° field of view. An FIM image or a desorption image of the atoms removed from the apex of a field emitter tip could be obtained. The 10-cm Atom Probe has been called the progenitor of later atom probes including the commercial instruments. ### Imaging Atom Probe {#imaging_atom_probe} The Imaging Atom-Probe (IAP) was introduced in 1974 by J. A. Panitz. It incorporated the features of the 10-cm Atom-Probe yet "\... departs completely from \[previous\] atom probe philosophy. Rather than attempt to determine the identity of a surface species producing a preselected ion-image spot, we wish to determine the complete crystallographic distribution of a surface species of preselected mass-to-charge ratio. Now suppose that instead of operating the \[detector\] continuously, it is turned on for a short time coincidentally with the arrival of a preselected species of interest by applying a gate pulse a time T after the evaporation pulse has reached the specimen. If the duration of the gate pulse is shorter than the travel time between adjacent species, only that surface species having the unique travel time T will be detected and its complete crystallographic distribution displayed." It was patented in 1975 as the Field Desorption Spectrometer. The Imaging Atom-Probe moniker was coined by A. J. Waugh in 1978 and the instrument was described in detail by J. A. Panitz in the same year. ### Atom Probe Tomography (APT) {#atom_probe_tomography_apt} Modern day atom probe tomography uses a position sensitive detector aka a FIM in a box to deduce the lateral location of atoms. The idea of the APT, inspired by J. A. Panitz\'s Field Desorption Spectrometer patent, was developed by Mike Miller starting in 1983 and culminated with the first prototype in 1986. Various refinements were made to the instrument, including the use of a so-called position-sensitive (PoS) detector by Alfred Cerezo, Terence Godfrey, and George D. W. Smith at Oxford University in 1988. The Tomographic Atom Probe (TAP), developed by researchers at the University of Rouen in France in 1993, introduced a multichannel timing system and multianode array. Both instruments (PoSAP and TAP) were commercialized by Oxford Nanoscience and CAMECA respectively. Since then, there have been many refinements to increase the field of view, mass and position resolution, and data acquisition rate of the instrument. The Local Electrode Atom Probe was first introduced in 2003 by Imago Scientific Instruments. In 2005, the commercialization of the pulsed laser atom probe (PLAP) expanded the avenues of research from highly conductive materials (metals) to poor conductors (semiconductors like silicon) and even insulating materials. AMETEK acquired CAMECA in 2007 and Imago Scientific Instruments (Madison, WI) in 2010, making the company the sole commercial developer of APTs with more than 110 instruments installed around the world in 2019. The first few decades of work with APT focused on metals. However, with the introduction of the laser pulsed atom probe systems applications have expanded to semiconductors, ceramic and geologic materials, with some work on biomaterials. The most advanced study of biological material to date using APT involved analyzing the chemical structure of teeth of the radula of chiton Chaetopleura apiculata. In this study, the use of APT showed chemical maps of organic fibers in the surrounding nano-crystalline magnetite in the chiton teeth, fibers which were often co-located with sodium or magnesium. This has been furthered to study elephant tusks, dentin and human enamel. ## Theory ### Field evaporation {#field_evaporation} Field evaporation is an effect that can occur when an atom bonded at the surface of a material is in the presence of a sufficiently high and appropriately directed electric field, where the electric field is the differential of electric potential (voltage) with respect to distance. Once this condition is met, it is sufficient that local bonding at the specimen surface is capable of being overcome by the field, allowing for evaporation of an atom from the surface to which it is otherwise bonded. ### Ion flight {#ion_flight} Whether evaporated from the material itself, or ionised from the gas, the ions that are evaporated are accelerated by electrostatic force, acquiring most of their energy within a few tip-radii of the sample. Subsequently, the accelerative force on any given ion is controlled by the electrostatic equation, where n is the ionisation state of the ion, and e is the fundamental electric charge. $$F=ne \nabla \phi$$ This can be equated with the mass of the ion, m, via Newton\'s law (F=ma): $$ma = q \nabla \phi$$ $$a = \frac{q}{m} \nabla \phi$$ Relativistic effects in the ion flight are usually ignored, as realisable ion speeds are only a very small fraction of the speed of light. Assuming that the ion is accelerated during a very short interval, the ion can be assumed to be travelling at constant velocity. As the ion will travel from the tip at voltage V~1~ to some nominal ground potential, the speed at which the ion is travelling can be estimated by the energy transferred into the ion during (or near) ionisation. Therefore, the ion speed can be computed with the following equation, which relates kinetic energy to energy gain due to the electric field, the negative arising from the loss of electrons forming a net positive charge. $$E = \frac{1}{2}mU_{\mathrm{ion}}^2 = -neV_1$$ Where U is the ion velocity. Solving for U, the following relation is found: $$U =\sqrt{ \frac{ 2neV_1}{m}}$$ Let\'s say that for at a certain ionization voltage, a singly charged hydrogen ion acquires a resulting velocity of 1.4x10\^6 ms^−1^ at 10\~kV. A singly charged deuterium ion under the sample conditions would have acquired roughly 1.4x10\^6/1.41 ms^−1^. If a detector was placed at a distance of 1 m, the ion flight times would be 1/1.4x10\^6 and 1.41/1.4x10\^6 s. Thus, the time of the ion arrival can be used to infer the ion type itself, if the evaporation time is known. From the above equation, it can be re-arranged to show that $$\frac{m}{n} = -\frac{2eV_1}{U^2}$$ given a known flight distance. F, for the ion, and a known flight time, t, $$U = \frac{f}{t}$$ and thus one can substitute these values to obtain the mass-to-charge for the ion. $$\frac{m}{n} = -2eV_1 \left(\frac{t}{f}\right)^2$$ Thus for an ion which traverses a 1 m flight path, across a time of 2000 ns, given an initial accelerating voltage of 5000 V (V in Si units is kg.m\^2.s\^-3.A\^-1) and noting that one amu is 1×10^−27^ kg, the mass-to-charge ratio (more correctly the mass-to-ionisation value ratio) becomes \~3.86 amu/charge. The number of electrons removed, and thus net positive charge on the ion is not known directly, but can be inferred from the histogram (spectrum) of observed ions. ### Magnification The magnification in an atom is due to the projection of ions radially away from the small, sharp tip. Subsequently, in the far-field, the ions will be greatly magnified. This magnification is sufficient to observe field variations due to individual atoms, thus allowing in field ion and field evaporation modes for the imaging of single atoms. The standard projection model for the atom probe is an emitter geometry that is based upon a revolution of a conic section, such as a sphere, hyperboloid or paraboloid. For these tip models, solutions to the field may be approximated or obtained analytically. The magnification for a spherical emitter is inversely proportional to the radius of the tip, given a projection directly onto a spherical screen, the following equation can be obtained geometrically. $$M = \frac{r_{screen}}{r_{tip}}.$$ Where r~screen~ is the radius of the detection screen from the tip centre, and r~tip~ the tip radius. A practical tip to screen distances may range from several centimeters to several meters, with increased detector area required at larger to subtend the same field of view. Practically speaking, the usable magnification will be limited by several effects, such as lateral vibration of the atoms prior to evaporation. Whilst the magnification of both the field ion and atom probe microscopes is extremely high, the exact magnification is dependent upon conditions specific to the examined specimen, so unlike for conventional electron microscopes, there is often little direct control on magnification, and furthermore, obtained images may have strongly variable magnifications due to fluctuations in the shape of the electric field at the surface. ### Reconstruction The computational conversion of the ion sequence data, as obtained from a position-sensitive detector to a three-dimensional visualisation of atomic types, is termed \"reconstruction\". Reconstruction algorithms are typically geometrically based and have several literature formulations. Most models for reconstruction assume that the tip is a spherical object, and use empirical corrections to stereographic projection to convert detector positions back to a 2D surface embedded in 3D space, R^3^. By sweeping this surface through R^3^ as a function of the ion sequence input data, such as via ion-ordering, a volume is generated onto which positions the 2D detector positions can be computed and placed three-dimensional space. Typically the sweep takes the simple form of advancement of the surface, such that the surface is expanded in a symmetric manner about its advancement axis, with the advancement rate set by a volume attributed to each ion detected and identified. This causes the final reconstructed volume to assume a rounded-conical shape, similar to a badminton shuttlecock. The detected events thus become a point cloud data with attributed experimentally measured values, such as ion time of flight or experimentally derived quantities, e.g. time of flight or detector data. This form of data manipulation allows for rapid computer visualisation and analysis, with data presented as point cloud data with additional information, such as each ion\'s mass to charge (as computed from the velocity equation above), voltage or other auxiliary measured quantity or computation therefrom. ### Data features {#data_features} The canonical feature of atom probe data, is its high spatial resolution in the direction through the material, which has been attributed to an ordered evaporation sequence. This data can therefore image near atomically sharp buried interfaces with the associated chemical information. The data obtained from the evaporative process is however not without artefacts that form the physical evaporation or ionisation process. A key feature of the evaporation or field ion images is that the data density is highly inhomogeneous, due to the corrugation of the specimen surface at the atomic scale. This corrugation gives rise to strong electric field gradients in the near-tip zone (on the order of an atomic radii or less from the tip), which during ionisation deflects ions away from the electric field normal. The resultant deflection means that in these regions of high curvature, atomic terraces are belied by a strong anisotropy in the detection density. Where this occurs due to a few atoms on a surface is usually referred to as a \"pole\", as these are coincident with the crystallographic axes of the specimen (FCC, BCC, HCP) etc. Where the edges of an atomic terrace causes deflection, a low density line is formed and is termed a \"zone line\". These poles and zone-lines, whilst inducing fluctuations in data density in the reconstructed datasets, which can prove problematic during post-analysis, are critical for determining information such as angular magnification, as the crystallographic relationships between features are typically well known. When reconstructing the data, owing to the evaporation of successive layers of material from the sample, the lateral and in-depth reconstruction values are highly anisotropic. Determination of the exact resolution of the instrument is of limited use, as the resolution of the device is set by the physical properties of the material under analysis. ## Systems Many designs have been constructed since the method\'s inception. Initial field ion microscopes, precursors to modern atom probes, were usually glass blown devices developed by individual research laboratories. ### System layout {#system_layout} At a minimum, an atom probe will consist of several key pieces of equipment. - A vacuum system for maintaining the low pressures (\~10^−8^ to 10^−10^ Pa) required, typically a classic 3 chambered UHV design. - A system for the manipulation of samples inside the vacuum, including sample viewing systems. - A cooling system to reduce atomic motion, such as a helium refrigeration circuit - providing sample temperatures as low as 15K. - A high voltage system to raise the sample standing voltage near the threshold for field evaporation. - A high voltage pulsing system, use to create timed field evaporation events - A counter electrode that can be a simple disk shape (like earlier generation atom probes), or a cone-shaped Local Electrode. The voltage pulse (negative) is typically applied to the counter electrode. - A detection system for single energetic ions that includes XY position and TOF information. Optionally, an atom probe may also include laser-optical systems for laser beam targeting and pulsing, if using laser-evaporation methods. In-situ reaction systems, heaters, or plasma treatment may also be employed for some studies as well as a pure noble gas introduction for FIM. ### Performance Collectable ion volumes were previously limited to several thousand, or tens of thousands of ionic events. Subsequent electronics and instrumentation development has increased the rate of data accumulation, with datasets of hundreds of million atoms (dataset volumes of 10^7^ nm^3^). Data collection times vary considerably depending upon the experimental conditions and the number of ions collected. Experiments take from a few minutes, to many hours to complete. ## Applications ### Metallurgy Atom probe has typically been employed in the chemical analysis of alloy systems at the atomic level. This has arisen as a result of voltage pulsed atom probes providing good chemical and sufficient spatial information in these materials. Metal samples from large grained alloys may be simple to fabricate, particularly from wire samples, with hand-electropolishing techniques giving good results. Subsequently, atom probe has been used in the analysis of the chemical composition of a wide range of alloys. Such data is critical in determining the effect of alloy constituents in a bulk material, identification of solid-state reaction features, such as solid phase precipitates. Such information may not be amenable to analysis by other means (e.g. TEM) owing to the difficulty in generating a three-dimensional dataset with composition. ### Semiconductors Semi-conductor materials are often analysable in atom probe, however sample preparation may be more difficult, and interpretation of results may be more complex, particularly if the semi-conductor contains phases which evaporate at differing electric field strengths. Applications such as ion implantation may be used to identify the distribution of dopants inside a semi-conducting material, which is increasingly critical in the correct design of modern nanometre scale electronics. ## Limitations - Materials implicitly control achievable spatial resolution. - Specimen geometry during the analysis is uncontrolled, yet controls projection behaviour, hence there is little control over the magnification. This induces distortions into the computer generated 3D dataset. Features of interest might evaporate in a physically different manner to the bulk sample, altering projection geometry and the magnification of the reconstructed volume. This yields strong spatial distortions in the final image. - Volume selectability can be limited. Site specific preparation methods, e.g. using Focussed ion beam preparation, although more time-consuming, may be used to bypass such limitations. - Ion overlap in some samples (e.g. between oxygen and sulfur) resulted in ambiguous analysed species. This may be mitigated by selection of experiment temperature or laser input energy to influence the ionisation number (+, ++, 3+ etc.) of the ionised groups. Data analysis can be used in some cases to statistically recover overlaps. - Low molecular weight gases (Hydrogen & Helium) may be difficult to be removed from the analysis chamber, and may be adsorbed and emitted from the specimen, even though not present in the original specimen. This may also limit identification of Hydrogen in some samples. For this reason, deuterated samples have been used to overcome limitations. - Results may be contingent on the parameters used to convert the 2D detected data into 3D. In more problematic materials, correct reconstruction may not be done, due to limited knowledge of the true magnification; particularly if zone or pole regions cannot be observed.	2025-06-20T00:00:00
3,212	Al Capone	Alphonse Gabriel Capone (`{{IPAc-en\|k\|ə\|ˈ\|p\|oʊ\|n}}`{=mediawiki} `{{respell\|kə\|POHN}}`{=mediawiki}; `{{IPA\|it\|kaˈpoːne\|lang}}`{=mediawiki}; January 17, 1899 -- January 25, 1947), sometimes known by the nickname \"Scarface\", was an American gangster and businessman who attained notoriety during the Prohibition era as the co-founder and boss of the Chicago Outfit from 1925 to 1931. His seven-year reign as a crime boss ended when he was imprisoned at the age of 33. Capone was born in New York City in 1899 to Italian immigrants. He joined the Five Points Gang as a teenager and became a bouncer in organized crime premises such as brothels. In his early twenties, Capone moved to Chicago and became a bodyguard of Johnny Torrio, head of a criminal syndicate that illegally supplied alcohol---the forerunner of the Outfit---and was politically protected through the Unione Siciliana. A conflict with the North Side Gang was instrumental in Capone\'s rise and fall. Torrio went into retirement after North Side gunmen almost killed him, handing control to Capone. Although Capone expanded the bootlegging business through increasingly violent means, his mutually profitable relationships with Mayor William Hale Thompson and the Chicago Police Department meant he seemed safe from law enforcement. Capone apparently reveled in attention, such as the cheers from spectators when he appeared at baseball games. He made donations to various charities and was viewed by many as a \"modern-day Robin Hood\". The Saint Valentine\'s Day Massacre, in which seven people from rival gangs were murdered in broad daylight, damaged the public image of Chicago and Capone, leading influential citizens to demand government action and newspapers to dub Capone \"Public Enemy No. 1\". Federal authorities became intent on jailing Capone and charged him with twenty-two counts of tax evasion. He was convicted of five counts in 1931. During a highly publicized case, the judge admitted as evidence Capone\'s admissions of his income and unpaid taxes, made during prior and ultimately abortive negotiations to pay the government taxes he owed. He was convicted and sentenced to eleven years in federal prison. After conviction, he replaced his defense team with experts in tax law, and his grounds for appeal were strengthened by a U.S. Supreme Court ruling, although his appeal ultimately failed. Capone showed signs of neurosyphilis early in his sentence and became increasingly debilitated before being released after almost eight years of incarceration. In 1947, he died of cardiac arrest after a stroke. ## Early life {#early_life} Alphonse Gabriel Capone was born in Brooklyn, a borough of New York City, on January 17, 1899. His parents were Italian immigrants Teresa (`{{née\|Raiola}}`{=mediawiki}; 1867--1952) and Gabriele Capone (1865--1920), both born in Angri, a small municipality outside of Naples in the province of Salerno. His father was a barber and his mother was a seamstress. Capone\'s family had immigrated to the United States in 1893 by ship, first going through the port city of Fiume, Austria-Hungary (modern-day Rijeka, Croatia). The family settled at 95 Navy Street, in the Brooklyn Navy Yard. When Capone was aged 11, he and his family moved to 38 Garfield Place in Park Slope, Brooklyn. Capone\'s parents had eight other children: James Vincenzo Capone, who later changed his name to Richard Hart and became a Prohibition agent in Homer, Nebraska; Raffaele James Capone, also known as Ralph Capone or \"Bottles\", who took charge of his brother\'s beverage industry; Salvatore \"Frank\" Capone; Ermina Capone, who died at the age of one; Ermino \"John\" Capone; Albert Capone; Matthew Capone and Mafalda Capone. Ralph and Frank worked with Al in his criminal empire. Frank did so until his death on April 1, 1924. Ralph ran Al\'s bottling companies (both legal and illegal) early on and was also the front man for the Chicago Outfit until he was imprisoned for tax evasion in 1932. Capone showed promise as a student but had trouble with the rules at his strict parochial Catholic school. His schooling ended at the age of 14 after he was expelled for hitting a female teacher in the face. Capone worked at odd jobs around Brooklyn, including a candy store and a bowling alley. From 1916 to 1918, he played semi-professional baseball. Following this, Capone was influenced by gangster Johnny Torrio, whom he came to regard as a mentor. Capone married Mae Josephine Coughlin at age 19, on December 30, 1918. She was Irish Catholic and earlier that month had given birth to their son Albert Francis \"Sonny\" Capone (1918--2004). Albert lost most of his hearing in his left ear as a child. Capone was under the age of 21, and his parents had to consent in writing to the marriage. By all accounts, the two had a happy marriage. ## Career ### New York City {#new_york_city} Capone initially became involved with small-time gangs that included the Junior Forty Thieves and the Bowery Boys. He then joined the Brooklyn Rippers, and then the powerful Five Points Gang based in Lower Manhattan. During this time he was employed and mentored by fellow racketeer Frankie Yale, a bartender in a Coney Island dance hall and saloon called the Harvard Inn. Capone inadvertently insulted a woman while working the door, and he was slashed with a knife three times on the left side of his face by her brother, Frank Galluccio; the wounds led to the nickname \"Scarface\", which Capone loathed. The date when this occurred has been reported with inconsistencies. When Capone was photographed, he hid the scarred left side of his face, saying that the injuries were war wounds. He was called \"Snorky\" by his closest friends, a term for a sharp dresser. ### Move to Chicago {#move_to_chicago} In 1919, Capone left New York City for Chicago at the invitation of Torrio, who was imported by crime boss James \"Big Jim\" Colosimo as an enforcer. Capone began in Chicago as a bouncer in a brothel, which is thought to be most likely where he contracted syphilis. Capone was aware of being infected at an early stage and timely use of Salvarsan probably could have cured the infection, but he apparently never sought treatment. In 1923, Capone purchased a small house at 7244 South Prairie Avenue in the Park Manor neighborhood in Chicago\'s South Side for `{{US$\|5500\|long=$}}`{=mediawiki}. As originally reported in the Chicago Tribune, hijacker Joe Howard was killed on May 8, 1924, after he tried to interfere with the Capone-Torrio bootlegging business. In a 1936 article highlighting Capone\'s criminal career, the Tribune erroneously reported the date as May 7, 1923. In the early years of the decade, Capone\'s name began appearing in newspaper sports pages where he was described as a boxing promoter. Torrio took over Colosimo\'s criminal empire after the latter\'s murder on May 11, 1920, in which Capone was suspected of being involved. Torrio headed an essentially Italian organized crime group that was the biggest in Chicago, with Capone as his right-hand man. Torrio was wary of being drawn into gang wars and tried to negotiate agreements over territory between rival crime groups. The smaller North Side Gang, led by Dean O\'Banion, came under pressure from the Genna brothers who were allied with Torrio. O\'Banion found that Torrio was unhelpful with the Gennas\' encroachment, despite his pretensions to be a settler of disputes. In a fateful step, Torrio arranged the murder of O\'Banion at his flower shop on November 10, 1924. This placed Hymie Weiss at the head of the gang, backed by Vincent Drucci and Bugs Moran. Weiss had been a close friend of O\'Banion, and the North Siders made it a priority to get revenge on his killers. During Prohibition, Capone was involved with Canadian bootleggers who helped him smuggle liquor into the U.S. When Capone was asked if he knew Rocco Perri, billed as Canada\'s \"King of the Bootleggers\", he replied: \"Why, I don\'t even know which street Canada is on.\" Other sources claim that Capone had certainly visited Canada, where he maintained some hideaways, although the Royal Canadian Mounted Police states that there is no \"evidence that he ever set foot on Canadian soil\". ### Boss An ambush in January 1925 left Capone shaken, but unhurt. Twelve days later, Torrio was returning from a shopping trip when he was shot several times. After recovering, he effectively resigned and handed control over to Capone, aged 26, who became the new boss of an organization that took in illegal breweries and a transportation network that reached to Canada, with political and law-enforcement protection. In turn, he was able to use more violence to increase revenue. Any establishment that refused to purchase liquor from Capone often got blown up, and as many as 100 people were killed in such bombings during the 1920s. Rivals saw Capone as responsible for the proliferation of brothels in the city. Capone often enlisted the help of local members of the black community into his operations; jazz musicians Milt Hinton and Lionel Hampton had uncles who worked for Capone on Chicago\'s South Side. A fan of jazz as well, Capone once asked clarinetist Johnny Dodds to play a number that Dodds did not know; Capone split a \$100 bill in half and told Dodds that he would get the other half when he learned it. Capone also sent two bodyguards to accompany jazz pianist Earl Hines on a road trip. Capone indulged in custom suits, cigars, gourmet food and drink, and female companionship. He was particularly known for his flamboyant and costly jewelry. His favorite responses to questions about his activities were \"I am just a businessman, giving the people what they want\" and \"All I do is satisfy a public demand\". Capone had become a national celebrity and talking point. Capone based himself in Cicero, Illinois, after using bribery and widespread intimidation to take over town council elections, making it difficult for the North Siders to target him. Capone\'s driver was found tortured and murdered, and there was an attempt on Weiss\' life in the Chicago Loop. On September 20, 1926, the North Siders used a ploy outside Capone\'s headquarters at the Hawthorne Inn aimed at drawing him to the windows. Gunmen in several cars then opened fire with Thompson submachine guns and shotguns at the windows of the first-floor restaurant. Capone was unhurt and called for a truce, but the negotiations fell flat. Three weeks later, on October 11, Weiss was killed outside the North Siders\' headquarters at O\'Banion\'s former flower shop. The owner of Hawthorne\'s restaurant was a friend of Capone\'s, and he was kidnapped and killed by Moran and Drucci in January 1927. Capone became increasingly security-minded and desirous of getting away from Chicago. As a precaution, he and his entourage would often show up suddenly at one of Chicago\'s train depots and buy up an entire Pullman sleeper car on a night train to Cleveland, Omaha, Kansas City, Little Rock, or Hot Springs, Arkansas, where they would spend a week in luxury hotel suites under assumed names. In 1928, Capone paid \$40,000 to Clarence Busch of the Anheuser-Busch brewing family for a 10000 sqfoot home at 93 Palm Avenue on Palm Island, Florida, between Miami and Miami Beach. ### Feud with Aiello {#feud_with_aiello} In November 1925, Antonio Lombardo, who was Capone\'s consigliere, was named head of the Unione Siciliana, a Sicilian-American benevolent society that had been corrupted by gangsters. An infuriated Joe Aiello, who had wanted the position himself, believed Capone was responsible for Lombardo\'s ascension and resented the non-Sicilian\'s attempts to manipulate affairs within the Unione. Aiello severed all personal and business ties with Lombardo and entered into a feud with Capone. Aiello allied himself with several of Capone enemies, including Jack Zuta, who ran vice and gambling houses together. Aiello plotted to eliminate both Lombardo and Capone, and starting in the spring of 1927, made several attempts to assassinate Capone. On one occasion, Aiello offered money to the chef of Joseph \"Diamond Joe\" Esposito\'s Bella Napoli Café, Capone\'s favorite restaurant, to put prussic acid in Capone\'s and Lombardo\'s soup; reports indicated he offered between \$10,000 and \$35,000. Instead, the chef exposed the plot to Capone, who responded by dispatching men to destroy Aiello\'s bakery on West Division Street with machine-gun fire. More than 200 bullets were fired into the bakery on May 28, 1927, wounding Aiello\'s brother Antonio. During the summer and autumn of 1927, a number of hitmen Aiello hired to kill Capone were themselves slain. Among them were Anthony Russo and Vincent Spicuzza, each of whom had been offered \$25,000 by Aiello to kill Capone and Lombardo. Aiello eventually offered a \$50,000 bounty to anyone who eliminated Capone. At least ten gunmen tried to collect on the bounty, but ended up dead. Capone\'s ally Ralph Sheldon attempted to kill both Capone and Lombardo for Aiello\'s reward, but Capone henchman, Frank Nitti, had an intelligence network that learned of the transaction and had Sheldon shot in front of a West Side hotel, although he survived the incident. In November 1927, Aiello organized machine-gun ambushes across from Lombardo\'s home and a cigar store frequented by Capone, but those plans were foiled after an anonymous tip led police to raid several addresses and arrest Milwaukee gunman Angelo La Mantio and four other Aiello gunmen. After the police discovered receipts for the apartments in La Mantio\'s pockets, he confessed that Aiello had hired him to kill Capone and Lombardo, leading the police to arrest Aiello himself and bring him to the South Clark Street police station. Upon learning of the arrest, Capone dispatched nearly two dozen gunmen to stand guard outside the station and await Aiello\'s release. The men made no attempt to conceal their purpose there, and reporters and photographers rushed to the scene to observe Aiello\'s expected murder. When released, Aiello was given a police escort out of the station to safety. He later failed to make a court appearance after his attorney claimed he suffered a nervous breakdown. Aiello disappeared with some family members to Trenton, New Jersey, where he continued his campaign against Capone and Lombardo. ### Political alliances {#political_alliances} Chicago politicians had long been associated with questionable methods, and even newspaper circulation \"wars\", but the need for bootleggers to have protection in city hall introduced a far more serious level of violence and graft. Capone is generally seen as having an appreciable effect in bringing about the victory of Republican mayoral candidate William Hale Thompson, who had campaigned on a platform of not enforcing Prohibition and at one time hinted that he\'d reopen illegal saloons. Thompson allegedly accepted a contribution of \$250,000 from Capone. Thompson beat Democratic candidate William Emmett Dever in the 1927 mayoral race by a relatively slim margin. On the day of the Pineapple Primary on April 10, 1928, voting booths were targeted by Capone\'s bomber, James Belcastro, in wards where Thompson\'s opponents were thought to have support, causing the deaths of at least fifteen people. Belcastro was accused of murdering lawyer Octavius Granady, an African-American, who challenged Thompson\'s candidate for the Black vote, and was chased through the streets on polling day by cars of gunmen before being shot dead. Four policemen were among those charged along with Belcastro, but all charges were dropped after key witnesses recanted their statements. An indication of the attitude of local law enforcement toward Capone\'s organization came in 1931 when Belcastro was wounded in a shooting; police suggested to skeptical journalists that Belcastro was an independent operator. A 1929 report by The New York Times connected Capone to the 1926 murder of Assistant State Attorney William H. McSwiggin, the 1928 murders of chief investigator Ben Newmark, and former mentor Frankie Yale. ### Saint Valentine\'s Day Massacre {#saint_valentines_day_massacre} Capone was widely assumed to have been responsible for ordering the 1929 Saint Valentine\'s Day Massacre, despite being at his Florida home at the time of the massacre. The massacre was an attempt to eliminate Bugs Moran, head of the North Side Gang, and the motivation for the plan may have been the fact that some expensive whisky that was illegally imported from Canada via the Detroit River had been hijacked while it was being transported to Cook County, Illinois. Moran was the last survivor of the North Side gunmen; his succession had come about because his similarly aggressive predecessors, Weiss and Vincent Drucci, had been killed in the violence that followed the murder of original leader Dean O\'Banion. To monitor their targets\' habits and movements, Capone\'s men rented an apartment across from the trucking warehouse and garage at 2122 North Clark Street, which served as Moran\'s headquarters. On the morning of Thursday, February 14, 1929, Capone\'s lookouts signaled four gunmen, disguised as police officers, to initiate a \"police raid\". The faux police lined the seven victims along a wall and signaled for accomplices armed with machine guns and shotguns. Moran was not among the victims. Photos of the slain victims shocked the public and damaged Capone\'s image. Within days, Capone received a summons to testify before a Chicago grand jury on charges of federal Prohibition violations, but he claimed to be too unwell to attend. In an effort to clean up his image, Capone donated to charities and sponsored a soup kitchen in Chicago during the Depression. The Saint Valentine\'s Day Massacre led to public outcry about Thompson\'s alliance with Capone, and this was a factor in Anton J. Cermak winning the mayoral election on April 6, 1931. ### Feud with Aiello ends {#feud_with_aiello_ends} Capone was known for ordering other men to do his work for him. In May 1929, one of Capone\'s bodyguards, Frank Rio, uncovered a plot by three of his men; Albert Anselmi, John Scalise and Joseph Giunta. They had been persuaded by Aiello to depose Capone and take over the Chicago Outfit. Later on, Capone beat the men with a baseball bat and then ordered his bodyguards to shoot them, a scene that was included in the 1987 film The Untouchables. Deirdre Bair, along with writers and historians such as William Elliot Hazelgrove, have questioned the veracity of the claim. Bair questioned why \"three trained killers could sit quietly and let this happen\", while Hazelgrove stated that Capone would have been \"hard pressed to beat three men to death with a baseball bat\" and that he would have instead let an enforcer perform the murders; however, despite claims that the story was first reported by author Walter Noble Burns in his 1931 book The One-Way Ride: The Red Trail of Chicago Gangland from Prohibition to Jake Lingle, Capone biographers Max Allan Collins and A. Brad Schwartz have found versions of the story in press coverage shortly after the crime. Collins and Schwartz suggest that similarities among reported versions of the story indicate a basis in truth and that the Outfit deliberately spread the tale to enhance Capone\'s fearsome reputation. George Meyer, an associate of Capone\'s, also claimed to have witnessed both the planning of the murders and the event itself. In 1930, upon learning of Aiello\'s continued plotting against him, Capone resolved to finally eliminate him. In the weeks before Aiello\'s death, Capone\'s men tracked him to Rochester, New York, where he had connections through Buffalo crime family boss Stefano Magaddino, and plotted to kill him there, but Aiello returned to Chicago before the plot could be executed. Aiello, angst-ridden from the constant need to hide out and the killings of several of his men, set up residence in the Chicago apartment of Unione Siciliana treasurer Pasquale \"Patsy Presto\" Prestogiacomo at 205 N. Kolmar Ave. On October 23, upon exiting Prestogiacomo\'s building to enter a taxicab, a gunman in a second-floor window across the street started firing at Aiello with a submachine gun. Aiello was said to have been shot at least 13 times before he toppled off the building steps and moved around the corner, attempting to move out of the line of fire. Instead, he moved directly into the range of a second submachine gun positioned on the third floor of another apartment block, and was subsequently gunned down. ### Federal intervention {#federal_intervention} In the wake of the Saint Valentine\'s Day Massacre, Walter A. Strong, publisher of the Chicago Daily News, asked his friend President Herbert Hoover for federal intervention to stem Chicago\'s lawlessness. He arranged a secret meeting at the White House, just two weeks after Hoover\'s inauguration. On March 19, 1929, Strong, joined by Frank Loesch of the Chicago Crime Commission, and Laird Bell, made their case to the President. In Hoover\'s 1952 Memoir, the former President reported that Strong argued \"Chicago was in the hands of the gangsters, that the police and magistrates were completely under their control, ...that the Federal government was the only force by which the city\'s ability to govern itself could be restored. At once I directed that all the Federal agencies concentrate upon Mr. Capone and his allies.\" That meeting launched a multi-agency attack on Capone. Treasury and Justice Departments developed plans for income tax prosecutions against Chicago gangsters, and a small, elite squad of Prohibition Bureau agents (whose members included Eliot Ness) were deployed against bootleggers. In a city used to corruption, these lawmen were incorruptible. Charles Schwarz, a writer for the Chicago Daily News, dubbed them Untouchables. To support Federal efforts, Strong secretly used his newspaper\'s resources to gather and share intelligence on the Capone outfit. ### Trials On March 27, 1929, Capone was arrested by FBI agents as he left a Chicago courtroom after testifying to a grand jury that was investigating violations of federal prohibition laws. He was charged with contempt of court for feigning illness to avoid an earlier appearance. On May 16, 1929, Capone was arrested in Philadelphia, Pennsylvania, for carrying a concealed weapon. On May 17, 1929, Capone was indicted by a grand jury and a trial was held before Philadelphia Municipal Court Judge John E Walsh. Entering a guilty plea by his attorney, Capone was sentenced to a prison term of one year. On August 8, 1929, Capone was transferred to Philadelphia\'s Eastern State Penitentiary. A week after his release in March 1930, Capone was listed as \"Public Enemy #1\" on the unofficial Chicago Crime Commission\'s widely publicized list. In April 1930, Capone was arrested on vagrancy charges when visiting Miami Beach; the governor had ordered sheriffs to run him out of the state. Capone claimed that Miami police had refused him food and water and threatened to arrest his family. He was charged with perjury for making these statements, but was acquitted after a three-day trial in July. In September, a Chicago judge issued a warrant for Capone\'s arrest on charges of vagrancy and then used the publicity to run against Thompson in the Republican primary. In February 1931, Capone was tried on the contempt of court charge. In court, Judge James Herbert Wilkerson, intervened to reinforce questioning of Capone\'s doctor by the prosecutor. Wilkerson sentenced Capone to six months, but he remained free while on appeal of the contempt conviction. In February 1930, Capone\'s organization was linked to the murder of Julius Rosenheim, who served as a police informant in the Chicago Outfit for 20 years. ### Tax evasion {#tax_evasion} U.S. Assistant Attorney General Mabel Walker Willebrandt is said to have originated the tactic of charging obviously wealthy crime figures with federal tax evasion on the basis of their luxurious lifestyles. In 1927, the U.S. Supreme Court ruled in United States v. Sullivan that the approach was legally sound: illegally earned income was subject to income tax. The key to Capone\'s conviction on tax charges was not his spending, but proving his income, and the most valuable evidence in that regard originated in his offer to pay tax. Ralph, his brother and a gangster in his own right, was tried for tax evasion in 1930. Ralph spent the next 18 months in prison after being convicted in a two-week trial over which Wilkerson presided. Seeking to avoid the same fate, Capone ordered his lawyer to regularize his tax position, and although it was not done, his lawyer made crucial admissions when stating the income that Capone was willing to pay tax on for various years, admitting income of \$100,000 for 1928 and 1929, for instance; hence, without any investigation, the government had been given a letter from a lawyer acting for Capone conceding his large taxable income for certain years he had paid no tax on. On March 13, 1931, Capone was charged with income tax evasion for 1924, in a secret grand jury. On June 5, 1931, Capone was indicted by a federal grand jury on 22 counts of income tax evasion from 1925 through 1929; he was released on \$50,000 bail. Capone was then indicted on 5,000 violations of the Volstead Act (Prohibition laws). On June 16, 1931, at the Chicago Federal Building in the courtroom of Wilkerson, Capone pleaded guilty to income tax evasion and the 5,000 Volstead Act violations as part of a `{{frac\|2\|1\|2}}`{=mediawiki}-year prison sentence plea bargain. On July 30, 1931, Wilkerson refused to honor the plea bargain, and Capone\'s counsel rescinded the guilty pleas. On the second day of the trial, Wilkerson deemed that the 1930 letter to federal authorities could be admitted into evidence, overruling objections that a lawyer could not confess for his client. Wilkerson later tried Capone only on the income tax evasion charges as he determined they took precedence over the Volstead Act charges. Much was later made of other evidence, such as witnesses and ledgers, but these strongly implied Capone\'s control rather than stating it. Capone\'s lawyers, who had relied on the plea bargain Wilkerson refused to honor, therefore had mere hours to prepare for the trial, ran a weak defense focused on claiming that essentially all his income was lost to gambling. This would have been irrelevant regardless, since gambling losses can only be subtracted from gambling winnings, but it was further undercut by Capone\'s expenses, which were well beyond what his claimed income could support; Wilkerson allowed Capone\'s spending to be presented at very great length. The government charged Capone with evasion of \$215,000 in taxes on a total income of \$1,038,654, during the five-year period. Capone was convicted on five counts of income tax evasion on October 17, 1931, and was sentenced a week later to 11 years in federal prison, fined \$50,000 plus \$7,692 for court costs, and was held liable for \$215,000 plus interest due on his back taxes. The contempt of court sentence was served concurrently. New lawyers hired to represent Capone were Washington-based tax experts. They filed a writ of habeas corpus based on a Supreme Court ruling that tax evasion was not fraud, which apparently meant that Capone had been convicted on charges relating to years that were actually outside the time limit for prosecution; however, a judge interpreted the law so that the time that Capone had spent in Miami was subtracted from the age of the offences, thereby denying the appeal of both Capone\'s conviction and sentence. ### Imprisonment Capone was sent to Atlanta U.S. Penitentiary in May 1932, aged 33. Upon his arrival at Atlanta, Capone was officially diagnosed with syphilis and gonorrhea. He was also experiencing withdrawal symptoms from cocaine addiction, the use of which had perforated his nasal septum. Capone was competent at his prison job of stitching soles on shoes for eight hours a day, but his letters were barely coherent. He was seen as a weak personality, and so out of his depth dealing with bullying at the hands of fellow inmates that his cellmate, seasoned convict Red Rudensky, feared that Capone would have a breakdown. Rudensky was formerly a small-time criminal associated with the Capone gang and found himself becoming a protector for Capone. The conspicuous protection by Rudensky and other prisoners drew accusations from less friendly inmates and fueled suspicion that Capone was receiving special treatment. No solid evidence ever emerged, but it formed part of the rationale for moving Capone to the recently opened Alcatraz Federal Penitentiary off the coast of San Francisco, in August 1934. On June 23, 1936, Capone was stabbed and superficially wounded by fellow Alcatraz inmate James C. Lucas. Due to his good behavior, Capone was permitted to play banjo in the Alcatraz prison band, the Rock Islanders, which gave regular Sunday concerts for other inmates. Capone also transcribed the song \"Madonna Mia\" creating his own arrangement as a tribute to his wife Mae. At Alcatraz, Capone\'s decline became increasingly evident, as neurosyphilis progressively eroded his mental faculties; his formal diagnosis of syphilis of the brain was made in February 1938. He spent the last year of his Alcatraz sentence in the hospital section, confused and disoriented. Capone completed his term in Alcatraz on January 6, 1939, and was transferred to the Federal Correctional Institution at Terminal Island in California to serve out his sentence for contempt of court. He was paroled on November 16, 1939, after his wife Mae appealed to the court, based on his reduced mental capabilities. ## Chicago aftermath {#chicago_aftermath} The main effect of Capone\'s conviction was that he ceased to be boss immediately on his imprisonment, but those involved in the jailing of Capone portrayed it as a considerable undermining of the city\'s organized crime syndicate. Capone\'s underboss, Frank Nitti, took over as boss of the Outfit after he was released from prison in March 1932, having also been convicted of tax evasion charges. Far from being smashed, the Outfit continued without being troubled by the Chicago police, but at a lower level and without the open violence that had marked Capone\'s rule. Organized crime in the city had a lower profile once Prohibition was repealed, already wary of attention after seeing Capone\'s notoriety bring him down, to the extent that there is a lack of consensus among writers about who was actually in control and who was a figurehead \"front boss\". Prostitution, labor union racketeering, and gambling became moneymakers for organized crime in the city without incurring serious investigation. In the late 1950s, FBI agents discovered an organization led by Capone\'s former lieutenants reigning supreme over the Chicago underworld. Some historians have speculated that Capone ordered the 1939 murder of Edward J. O\'Hare a week before his release, for helping federal prosecutors convict Capone of tax evasion, though there are other theories for O\'Hare\'s death. ## Illness and death {#illness_and_death} Due to his failing health, Capone was released from prison on November 16, 1939, and referred to Johns Hopkins Hospital in Baltimore for the treatment of syphilitic paresis. Because of his unsavory reputation, Johns Hopkins refused to treat him, but Baltimore\'s Union Memorial Hospital did. Capone was grateful for the compassionate care that he received and donated two Japanese weeping cherry trees to Union Memorial Hospital in 1939.`{{better source needed\|date=September 2024}}`{=mediawiki} After a few weeks of inpatient and outpatient care, on March 20, 1940, a very sickly Capone left Baltimore and travelled to his mansion in Palm Island, Florida. In 1942, after mass production of penicillin was started in the United States, Capone was one of the first American patients treated by the new drug. Though it was too late for him to reverse the damage to his brain, it did slow down the progression of the disease. In 1946, his physician and a Baltimore psychiatrist examined him and concluded that Capone had the mentality of a 12-year-old child. He spent the last years of his life at his Palm Island mansion, spending time with his wife and grandchildren. On January 21, 1947, Capone had a stroke. He regained consciousness and started to improve, but contracted bronchopneumonia. He suffered a cardiac arrest on January 22, and on January 25, surrounded by his family in his home, died after his heart failed as a result of apoplexy. His body was transported back to Chicago a week later and a private funeral was held. He was originally buried at Mount Olivet Cemetery in Chicago. In 1950, Capone\'s remains, along with those of his father, Gabriele, and brother, Frank, were moved to Mount Carmel Cemetery in Hillside, Illinois. <File:Death> certificate of Al Capone.jpg\\|Capone\'s death certificate January 25, 1947 <File:Grave> Al Capone.jpg\\|Capone\'s grave in Mount Carmel Cemetery, Hillside, Illinois ## In popular culture {#in_popular_culture} Capone is one of the most notorious American gangsters of the 20th century and has been the major subject of numerous articles, books, and films. Particularly, from 1925 to 1929, shortly after he moved to Chicago, he enjoyed his status as the most notorious mobster in the country. He cultivated a certain image of himself in the media that made him a subject of fascination.	2025-06-20T00:00:00
3,214	Amplifier figures of merit	In electronics, the figures of merit of an amplifier are numerical measures that characterize its properties and performance. Figures of merit can be given as a list of specifications that include properties such as gain, bandwidth, noise and linearity, among others listed in this article. Figures of merit are important for determining the suitability of a particular amplifier for an intended use. ## Gain The gain of an amplifier is the ratio of output to input power or amplitude, and is usually measured in decibels. When measured in decibels it is logarithmically related to the power ratio: G(dB)=10 log(P~out~ /P~in~). RF amplifiers are often specified in terms of the maximum power gain obtainable, while the voltage gain of audio amplifiers and instrumentation amplifiers will be more often specified. For example, an audio amplifier with a gain given as 20 dB will have a voltage gain of ten. The use of voltage gain figure is appropriate when the amplifier\'s input impedance is much higher than the source impedance, and the load impedance higher than the amplifier\'s output impedance. If two equivalent amplifiers are being compared, the amplifier with higher gain settings would be more sensitive as it would take less input signal to produce a given amount of power.`{{unreliable source?\|date=November 2017}}`{=mediawiki} ## Bandwidth The bandwidth of an amplifier is the range of frequencies for which the amplifier gives \"satisfactory performance\". The definition of \"satisfactory performance\" may be different for different applications. However, a common and well-accepted metric is the half-power points (i.e. frequency where the power goes down by half its peak value) on the output vs. frequency curve. Therefore, bandwidth can be defined as the difference between the lower and upper half power points. This is therefore also known as the `{{nowrap\|−3 dB}}`{=mediawiki} bandwidth. Bandwidths (otherwise called \"frequency responses\") for other response tolerances are sometimes quoted (`{{nowrap\|−1 dB}}`{=mediawiki}, `{{nowrap\|−6 dB}}`{=mediawiki} etc.) or \"plus or minus 1dB\" (roughly the sound level difference people usually can detect). The gain of a good quality full-range audio amplifier will be essentially flat between 20 Hz to about 20 kHz (the range of normal human hearing). In ultra-high-fidelity amplifier design, the amplifier\'s frequency response should extend considerably beyond this (one or more octaves either side) and might have `{{nowrap\|−3 dB}}`{=mediawiki} points \< 10 Hz and \> `{{nowrap\|65 kHz}}`{=mediawiki}. Professional touring amplifiers often have input and/or output filtering to sharply limit frequency response beyond `{{nowrap\|20 Hz-20 kHz}}`{=mediawiki}; too much of the amplifier\'s potential output power would otherwise be wasted on infrasonic and ultrasonic frequencies, and the danger of AM radio interference would increase. Modern switching amplifiers need steep low pass filtering at the output to get rid of high-frequency switching noise and harmonics. The range of frequency over which the gain is equal to or greater than 70.7% of its maximum gain is termed as bandwidth. ## Efficiency Efficiency is a measure of how much of the power source is usefully applied to the amplifier\'s output. Class A amplifiers are very inefficient, in the range of 10--20% with a max efficiency of 25% for direct coupling of the output. Inductive coupling of the output can raise their efficiency to a maximum of 50%. Drain efficiency is the ratio of output RF power to input DC power when primary input DC power has been fed to the drain of a field-effect transistor. Based on this definition, the drain efficiency cannot exceed 25% for a class A amplifier that is supplied drain bias current through resistors (because RF signal has its zero level at about 50% of the input DC). Manufacturers specify much higher drain efficiencies, and designers are able to obtain higher efficiencies by providing current to the drain of the transistor through an inductor or a transformer winding. In this case the RF zero level is near the DC rail and will swing both above and below the rail during operation. While the voltage level is above the DC rail current is supplied by the inductor. Class B amplifiers have a very high efficiency but are impractical for audio work because of high levels of distortion (See: Crossover distortion). In practical design, the result of a tradeoff is the class AB design. Modern Class AB amplifiers commonly have peak efficiencies between 30 and 55% in audio systems and 50-70% in radio frequency systems with a theoretical maximum of 78.5%. Commercially available Class D switching amplifiers have reported efficiencies as high as 90%. Amplifiers of Class C-F are usually known to be very high-efficiency amplifiers. RCA manufactured an AM broadcast transmitter employing a single class-C low-mu triode with an RF efficiency in the 90% range. More efficient amplifiers run cooler, and often do not need any cooling fans even in multi-kilowatt designs. The reason for this is that the loss of efficiency produces heat as a by-product of the energy lost during the conversion of power. In more efficient amplifiers there is less loss of energy so in turn less heat. In RF linear Power Amplifiers, such as cellular base stations and broadcast transmitters, special design techniques can be used to improve efficiency. Doherty designs, which use a second output stage as a \"peak\" amplifier, can lift efficiency from the typical 15% up to 30-35% in a narrow bandwidth. Envelope Tracking designs are able to achieve efficiencies of up to 60%, by modulating the supply voltage to the amplifier in line with the envelope of the signal. ## Linearity`{{anchor\|linearity}}`{=mediawiki} An ideal amplifier would be a totally linear device, but real amplifiers are only linear within limits. When the signal drive to the amplifier is increased, the output also increases until a point is reached where some part of the amplifier becomes saturated and cannot produce any more output; this is called clipping, and results in distortion. In most amplifiers a reduction in gain takes place before hard clipping occurs; the result is a compression effect, which (if the amplifier is an audio amplifier) sounds much less unpleasant to the ear. For these amplifiers, the 1 dB compression point is defined as the input power (or output power) where the gain is 1 dB less than the small signal gain. Sometimes this non linearity is deliberately designed in to reduce the audible unpleasantness of hard clipping under overload. Ill effects of non-linearity can be reduced with negative feedback. Linearization is an emergent field, and there are many techniques, such as feed forward, predistortion, postdistortion, in order to avoid the undesired effects of the non-linearities. ## Noise This is a measure of how much noise is introduced in the amplification process. Noise is an undesirable but inevitable product of the electronic devices and components; also, much noise results from intentional economies of manufacture and design time. The metric for noise performance of a circuit is noise figure or noise factor. Noise figure is a comparison between the output signal to noise ratio and the thermal noise of the input signal. ## Output dynamic range {#output_dynamic_range} Output dynamic range is the range, usually given in dB, between the smallest and largest useful output levels. The lowest useful level is limited by output noise, while the largest is limited most often by distortion. The ratio of these two is quoted as the amplifier dynamic range. More precisely, if S = maximal allowed signal power and N = noise power, the dynamic range DR is DR = (S + N ) /N. In many switched mode amplifiers, dynamic range is limited by the minimum output step size. ## Slew rate {#slew_rate} Slew rate is the maximum rate of change of the output, usually quoted in volts per second (or microsecond). Many amplifiers are ultimately slew rate limited (typically by the impedance of a drive current having to overcome capacitive effects at some point in the circuit), which sometimes limits the full power bandwidth to frequencies well below the amplifier\'s small-signal frequency response. ## Rise time {#rise_time} The rise time, t~r~, of an amplifier is the time taken for the output to change from 10% to 90% of its final level when driven by a step input. For a Gaussian response system (or a simple RC roll off), the rise time is approximated by: *t~r~ \ BW = 0.35**, where t~r~ is rise time in seconds and BW is bandwidth in Hz. ## Settling time and ringing {#settling_time_and_ringing} The time taken for the output to settle to within a certain percentage of the final value (for instance 0.1%) is called the settling time, and is usually specified for oscilloscope vertical amplifiers and high-accuracy measurement systems. Ringing refers to an output variation that cycles above and below an amplifier\'s final value and leads to a delay in reaching a stable output. Ringing is the result of overshoot caused by an underdamped circuit. ## Overshoot In response to a step input, the overshoot is the amount the output exceeds its final, steady-state value. ## Stability Stability is an issue in all amplifiers with feedback, whether that feedback is added intentionally or results unintentionally. It is especially an issue when applied over multiple amplifying stages. Stability is a major concern in RF and microwave amplifiers. The degree of an amplifier\'s stability can be quantified by a so-called stability factor. There are several different stability factors, such as the Stern stability factor and the Linvil stability factor, which specify a condition that must be met for the absolute stability of an amplifier in terms of its two-port parameters.	2025-06-20T00:00:00
3,221	Ahmed al-Nami	Ahmed bin Abdullah al-Nami (translit=Aḥmad bin 'Abd Allāh al-Nāʿmī; 7 December 1977 `{{Snd}}`{=mediawiki}11 September 2001) was a Saudi terrorist hijacker. He was one of the four hijackers of United Airlines Flight 93, which was crashed into a field in Stonycreek Township, Pennsylvania, following a passenger revolt, as part of the 11 September attacks. Born in Saudi Arabia, al-Nami had served as a muezzin and was a college student. He left his family in 2000 to complete the Hajj, but later went to Afghanistan bound for an al-Qaeda training camp where he befriended other future hijackers and would soon be chosen to participate in the attacks. He arrived in the United States in May 2001, on a tourist visa, where he would settle in Florida up until the attacks. On 11 September 2001, al-Nami boarded United 93 and assisted in the hijacking of the plane so that it could be flown into the U.S. Capitol. The plane instead crashed into a field in rural Somerset County, Pennsylvania during a passenger uprising, due to the passengers receiving information from their families of the three other hijacked planes that hit the World Trade Center and the Pentagon. Al-Nami, along with Ahmed al-Haznawi, are suspected to have carried the presumed bomb that was brought aboard Flight 93. ## Early life and activities {#early_life_and_activities} Ahmed al-Nami, like Wail al-Shehri, Waleed al-Shehri, and Mohand al-Shehri, was born in the \'Asir Province in Saudi Arabia. Born to the Quraysh tribe of Saudi Arabia, al-Nami served as a muezzin at the Seqeley mosque after having reportedly become very religious sometime in early 1999. That autumn he left his family home in Abha in the summer of 2000 to complete the Hajj, but never returned -- instead travelling to the Al Farouq training camp in Afghanistan where he met and befriended Waleed and Wail al-Shehri, two brothers from Khamis Mushayt in the same province, and Saeed al-Ghamdi. The four reportedly pledged themselves to Jihad in the spring of 2000, in a ceremony presided over by Wail al-Shehri -- who had dubbed himself Abu Mossaeb al-Janubi after one of Muhammad\'s companions. Dubbed \"Abu Hashim\", al-Nami was considered \"gentle in manner\" by his colleagues, and reported that he had a dream in which he rode a mare along with Muhammad, and that the prophet told him to dismount and fight his enemies to liberate his land. During his time at al-Farooq, there is a curious mention under Mushabib al-Hamlan\'s details that al-Nami had recently had laser eye surgery, an uncited fact that does not reappear. By October he had taken a prospective hijacker Mushabib al-Hamlan from Afghanistan to Saudi Arabia where they both procured B-1/B-2 tourist/business visas on 28 October -- but al-Hamlan then decided not to proceed and is thought to have returned to his family. al-Nami\'s visa application has since been reviewed, and while he mentioned that al-Hamlan will be travelling with him, he listed his occupation as student but failed to provide an address for his school, and listed his intended address in the United States merely as Los Angeles -- in the end he never used this visa to enter the United States, and reported his passport (C115007, which showed evidence of travel to Afghanistan) as \"lost\", and procured a new one from Jeddah (C505363). He used the new passport to acquire a new B-1/B-2 visa in Jeddah on 23 April, again recopying his answers from previously although crossing out the lines regarding al-Hamlan and previous attempts to acquire a visa. He was interviewed by a consular officer, who again approved his application. Records at the time only recorded past failures to procure a visa, so the officer had no way of realising that Nami had successfully received an earlier visa. In mid-November 2000, the 9/11 Commission believed that al-Nami, Wail, and Waleed al-Shehri, all of whom had obtained their U.S. visas in late October, traveled in a group from Saudi Arabia to Beirut and then onward to Iran where they could travel through to Afghanistan without getting their passports stamped. This probably followed their return to Saudi Arabia to get \"clean\" passports. An associate of a senior Hezbollah operative is thought to have been on the same flight, although this may have been a coincidence. While in the United Arab Emirates, al-Nami purchased traveler\'s cheques presumed to have been paid for by Mustafa al-Hawsawi. Five other hijackers also passed through the UAE and purchased travellers cheques, including Majed Moqed, Saeed al-Ghamdi, Hamza al-Ghamdi, Ahmed al-Haznawi, and Wail al-Shehri. ### 2001 In March 2001, Ahmed al-Nami appeared in an al-Qaeda farewell video showing 13 of the \"muscle hijackers\" before they left their training centre in Kandahar; while he does not speak, he is seen studying maps and flight manuals. On 23 April, al-Nami was recorded obtaining a new US visa. On 28 May, al-Nami arrived in the United States from Dubai with fellow-hijackers Mohand al-Shehri and Hamza al-Ghamdi. By early June, al-Nami was living in apartment 1504 at the Delray Racquet Club condominiums with Saeed al-Ghamdi in Delray Beach, Florida. He telephoned his family in \'Asir shortly after arriving in the country. In June, he phoned his family for the last time. He was one of 9 hijackers to open a SunTrust bank account with a cash deposit around June 2001, and on June 29 received either a Florida State Identification Card or Drivers License. He may have been one of three hijackers that listed the Naval Air Station in Pensacola, Florida as their permanent address on drivers\' licenses, though other sources claim he listed the Delray condominium. On 28 August, al-Nami and Ahmed al-Haznawi reportedly bothered a Delray Beach resident, Maria Siscar Simpson, to let them through her apartment to retrieve a towel that had fallen off their balcony onto hers. On 5 September, al-Nami and Saeed al-Ghamdi purchased tickets for a September 7 flight to Newark at Mile High Travel on Commercial Boulevard---paying cash for their tickets. Ziad Jarrah and al-Haznawi also purchased tickets for the same flight from Passage Tours. On 7 September, all four Flight 93 hijackers flew from Fort Lauderdale to Newark International Airport aboard Spirit Airlines. ## Attacks On 11 September 2001, al-Nami arrived in Newark to board United Airlines Flight 93 along with al-Ghamdi, al-Haznawi, and Jarrah. Some reports suggest al-Haznawi was pulled aside for screening while others claim there is no record of whether any of the four were screened; the lack of CCTV cameras at the time has compounded the problem. al-Nami boarded the plane between 7:39 am and 7:48 am; seated in First Class 3C, next to al-Ghamdi. Due to the flight\'s routine delay, the pilot and crew were notified of the previous hijackings and were told to be on the alert, though within two minutes Jarrah had stormed the cockpit leaving the pilots dead or injured. At least two of the cellphone calls made by passengers indicate that the hijackers were wearing red bandanas. The calls also indicated that one had tied a box around his torso, and claimed there was a bomb inside. Passengers on the plane heard through phone calls the fates of the other hijacked planes, and organized a brief assault to retake the cockpit. The plane crashed into the Pennsylvanian countryside and all aboard died. ## Aftermath - He has been portrayed by British actor Jamie Harding in the 2006 film United 93 and Asim Wali in the film Flight 93. - Television film The Flight That Fought Back (2005) portrays the passenger uprising inside the hijacked United Airlines 93, with actor Raj Mann portraying Ahmed al-Nami.	2025-06-20T00:00:00
3,231	Absolute infinite	The absolute infinite (symbol: Ω), in context often called \"absolute\", is an extension of the idea of infinity proposed by mathematician Georg Cantor. Cantor linked the absolute infinite with God, and believed that it had various mathematical properties, including the reflection principle: every property of the absolute infinite is also held by some smaller object.`{{clarify\|reason=The 'defining' property, i.e. that of being 'bigger than any (other) conceivable or inconceivable quantity', cannot be held by any smaller object.\|date=December 2021}}`{=mediawiki} ## Cantor\'s view {#cantors_view} Cantor said: }} While using the Latin expression in Deo (in God), Cantor identifies absolute infinity with God (GA 175--176, 376, 378, 386, 399). According to Cantor, Absolute Infinity is beyond mathematical comprehension and shall be interpreted in terms of negative theology. Cantor also mentioned the idea in his letters to Richard Dedekind (text in square brackets not present in original):`{{refn\|''Gesammelte Abhandlungen'',<ref name="Cantor.1932"/> Georg Cantor, ed. Ernst Zermelo, Hildesheim: Georg Olms Verlagsbuchhandlung, 1962, pp. 443–447; translated into English in ''From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931'', ed. Jean van Heijenoort, Cambridge, Massachusetts: Harvard University Press, 1967, pp. 113–117. These references both purport to be a letter from Cantor to Dedekind, dated July 28, 1899. However, as [[Ivor Grattan-Guinness]] has discovered,<ref>[https://eudml.org/doc/146637 The Rediscovery of the Cantor-Dedekind Correspondence], I. Grattan-Guinness, ''Jahresbericht der Deutschen Mathematiker-Vereinigung'' '''76''' (1974/75), pp. 104–139, at p. 126 ff.</ref> this is in fact an amalgamation by Cantor's editor, [[Ernst Zermelo]], of two letters from Cantor to Dedekind, the first dated July 28 and the second dated August 3.\|name=GesammelteAbhandlungen}}`{=mediawiki} ## The Burali-Forti paradox {#the_burali_forti_paradox} The idea that the collection of all ordinal numbers cannot logically exist seems paradoxical to many. This is related to the Burali-Forti\'s paradox which implies that there can be no greatest ordinal number. All of these problems can be traced back to the idea that, for every property that can be logically defined, there exists a set of all objects that have that property. However, as in Cantor\'s argument (above), this idea leads to difficulties. More generally, as noted by A. W. Moore, there can be no end to the process of set formation, and thus no such thing as the totality of all sets, or the set hierarchy. Any such totality would itself have to be a set, thus lying somewhere within the hierarchy and thus failing to contain every set. A standard solution to this problem is found in Zermelo set theory, which does not allow the unrestricted formation of sets from arbitrary properties. Rather, we may form the set of all objects that have a given property and lie in some given set (Zermelo\'s Axiom of Separation). This allows for the formation of sets based on properties, in a limited sense, while (hopefully) preserving the consistency of the theory. While this solves the logical problem, one could argue that the philosophical problem remains. It seems natural that a set of individuals ought to exist, so long as the individuals exist. Indeed, naive set theory might be said to be based on this notion. Although Zermelo\'s fix allows a class to describe arbitrary (possibly \"large\") entities, these predicates of the metalanguage may have no formal existence (i.e., as a set) within the theory. For example, the class of all sets would be a proper class. This is philosophically unsatisfying to some and has motivated additional work in set theory and other methods of formalizing the foundations of mathematics such as New Foundations by Willard Van Orman Quine.	2025-06-20T00:00:00
3,233	Acceptance testing	In engineering and its various subdisciplines, acceptance testing is a test conducted to determine if the requirements of a specification or contract are met. It may involve chemical tests, physical tests, or performance tests. In systems engineering, it may involve black-box testing performed on a system (for example: a piece of software, lots of manufactured mechanical parts, or batches of chemical products) prior to its delivery. In software testing, the ISTQB defines acceptance testing as: `{{Blockquote\|text=Formal testing with respect to user needs, requirements, and business processes conducted to determine whether a system satisfies the [[acceptance criteria]]<ref>{{Cite web \|date=2019-06-10 \|title=acceptance criteria \|url=https://innolution.com/resources/glossary/acceptance-criteria \|publisher=Innolution, LLC}}</ref> and to enable the user, customers or other authorized entity to determine whether to accept the system.\|source=Standard Glossary of Terms used in Software Testing<ref>{{Cite web \|title=Standard Glossary of Terms used in Software Testing, Version 3.2: All Terms \|url=https://glossary.istqb.org\|access-date=November 23, 2020 \|publisher=[[International Software Testing Qualifications Board\|ISTQB]] \|format=PDF}}</ref>{{rp\|2}} \|title=\|author=}}`{=mediawiki} The final test in the QA lifecycle, user acceptance testing, is conducted just before the final release to assess whether the product or application can handle real-world scenarios. By replicating user behavior, it checks if the system satisfies business requirements and rejects changes if certain criteria are not met. Some forms of acceptance testing are, user acceptance testing (UAT), end-user testing, operational acceptance testing (OAT), acceptance test-driven development (ATDD) and field (acceptance) testing. Acceptance criteria are the criteria that a system or component must satisfy in order to be accepted by a user, customer, or other authorized entity. ## Overview Testing is a set of activities conducted to facilitate the discovery and/or evaluation of properties of one or more items under test. Each test, known as a test case, exercises a set of predefined test activities, developed to drive the execution of the test item to meet test objectives; including correct implementation, error identification, quality verification, and other valued details. The test environment is usually designed to be identical, or as close as possible, to the anticipated production environment. It includes all facilities, hardware, software, firmware, procedures, and/or documentation intended for or used to perform the testing of software. UAT and OAT test cases are ideally derived in collaboration with business customers, business analysts, testers, and developers. These tests must include both business logic tests as well as operational environment conditions. The business customers (product owners) are the primary stakeholders of these tests. As the test conditions successfully achieve their acceptance criteria, the stakeholders are reassured the development is progressing in the right direction. - User acceptance test (UAT) criteria (in agile software development) are usually created by business customers and expressed in a business domain language. These are high-level tests to verify the completeness of a user story or stories \'played\' during any sprint/iteration. - Operational acceptance test (OAT) criteria (regardless of using agile, iterative, or sequential development) are defined in terms of functional and non-functional requirements; covering key quality attributes of functional stability, portability, and reliability. ## Process The acceptance test suite may need to be performed multiple times, as all of the test cases may not be executed within a single test iteration. The acceptance test suite is run using predefined acceptance test procedures to direct the testers on which data to use, the step-by-step processes to follow, and the expected result following execution. The actual results are retained for comparison with the expected results. If the actual results match the expected results for each test case, the test case is said to pass. If the quantity of non-passing test cases does not breach the project\'s predetermined threshold, the test suite is said to pass. If it does, the system may either be rejected or accepted on conditions previously agreed between the sponsor and the manufacturer. The anticipated result of a successful test execution: - test cases are executed, using predetermined data - actual results are recorded - actual and expected results are compared, and - test results are determined. The objective is to provide confidence that the developed product meets both the functional and non-functional requirements. The purpose of conducting acceptance testing is that once completed, and provided the acceptance criteria are met, it is expected the sponsors will sign off on the product development/enhancement as satisfying the defined requirements (previously agreed between business and product provider/developer). ## User acceptance testing {#user_acceptance_testing} User acceptance testing (UAT) consists of a process of verifying that a solution works for the user. It is not system testing (ensuring software does not crash and meets documented requirements) but rather ensures that the solution will work for the user (i.e. tests that the user accepts the solution); software vendors often refer to this as \"Beta testing\". This testing should be undertaken by the intended end user, or a subject-matter expert (SME), preferably the owner or client of the solution under test and provide a summary of the findings for confirmation to proceed after trial or review. In software development, UAT as one of the final stages of a project often occurs before a client or customer accepts the new system. Users of the system perform tests in line with what would occur in real-life scenarios. The materials given to the tester must be similar to the materials that the end user will have. Testers should be given real-life scenarios such as the three most common or difficult tasks that the users they represent will undertake. The UAT acts as a final verification of the required business functionality and proper functioning of the system, emulating real-world conditions on behalf of the paying client or a specific large customer. If the software works as required and without issues during normal use, one can reasonably extrapolate the same level of stability in production. User tests, usually performed by clients or by end-users, do not normally focus on identifying simple cosmetic problems such as spelling errors, nor on showstopper defects, such as software crashes; testers and developers identify and fix these issues during earlier unit testing, integration testing, and system testing phases. UAT should be executed against test scenarios. Test scenarios usually differ from System or Functional test cases in that they represent a \"player\" or \"user\" journey. The broad nature of the test scenario ensures that the focus is on the journey and not on technical or system-specific details, staying away from \"click-by-click\" test steps to allow for a variance in users\' behavior. Test scenarios can be broken down into logical \"days\", which are usually where the actor (player/customer/operator) or system (backoffice, front end) changes. In industry, a common UAT is a factory acceptance test (FAT). This test takes place before the installation of the equipment. Most of the time testers not only check that the equipment meets the specification but also that it is fully functional. A FAT usually includes a check of completeness, a verification against contractual requirements, a proof of functionality (either by simulation or a conventional function test), and a final inspection. The results of these tests give clients confidence in how the system will perform in production. There may also be legal or contractual requirements for acceptance of the system. ## Operational acceptance testing {#operational_acceptance_testing} Operational acceptance testing (OAT) is used to conduct operational readiness (pre-release) of a product, service or system as part of a quality management system. OAT is a common type of non-functional software testing, used mainly in software development and software maintenance projects. This type of testing focuses on the operational readiness of the system to be supported, and/or to become part of the production environment. ## Acceptance testing in extreme programming {#acceptance_testing_in_extreme_programming} Acceptance testing is a term used in agile software development methodologies, particularly extreme programming, referring to the functional testing of a user story by the software development team during the implementation phase. The customer specifies scenarios to test when a user story has been correctly implemented. A story can have one or many acceptance tests, whatever it takes to ensure the functionality works. Acceptance tests are black-box system tests. Each acceptance test represents some expected result from the system. Customers are responsible for verifying the correctness of the acceptance tests and reviewing test scores to decide which failed tests are of highest priority. Acceptance tests are also used as regression tests prior to a production release. A user story is not considered complete until it has passed its acceptance tests. This means that new acceptance tests must be created for each iteration, or the development team will report zero progress. ## Types of acceptance testing {#types_of_acceptance_testing} Typical types of acceptance testing include the following User acceptance testing:This may include factory acceptance testing (FAT), i.e. the testing done by a vendor before the product or system is moved to its destination site, after which site acceptance testing (SAT) may be performed by the users at the site.\ Operational acceptance testing:Also known as operational readiness testing, this refers to the checking done to a system to ensure that processes and procedures are in place to allow the system to be used and maintained. This may include checks done to back-up facilities, procedures for disaster recovery, training for end users, maintenance procedures, and security procedures.\ Contract and regulation acceptance testing : In contract acceptance testing, a system is tested against acceptance criteria as documented in a contract, before the system is accepted. In regulation acceptance testing, a system is tested to ensure it meets governmental, legal and safety standards. ```{=html} <!-- --> ``` Factory acceptance testing : Acceptance testing conducted at the site at which the product is developed and performed by employees of the supplier organization, to determine whether a component or system satisfies the requirements, normally including hardware as well as software. ```{=html} <!-- --> ``` Alpha and beta testing : Alpha testing takes place at developers\' sites and involves testing of the operational system by internal staff, before it is released to external customers. Beta testing takes place at customers\' sites and involves testing by a group of customers who use the system at their own locations and provide feedback, before the system is released to other customers. The latter is often called \"field testing\". ## Acceptance criteria {#acceptance_criteria} According to the Project Management Institute, acceptance criteria is a \"set of conditions that is required to be met before deliverables are accepted.\" Requirements found in acceptance criteria for a given component of the system are usually very detailed. ## List of acceptance-testing frameworks {#list_of_acceptance_testing_frameworks} - Concordion, Specification by example (SbE) framework - Concordion.NET, acceptance testing in .NET - Cucumber, a behavior-driven development (BDD) acceptance test framework - Capybara, Acceptance test framework for Ruby web applications - Behat, BDD acceptance framework for PHP - Lettuce, BDD acceptance framework for Python - Cypress - Fabasoft app.test for automated acceptance tests - Framework for Integrated Test (Fit) - FitNesse, a fork of Fit - Gauge (software), Test Automation Framework from Thoughtworks - iMacros - ItsNat Java Ajax web framework with built-in, server based, functional web testing capabilities. - Maveryx Test Automation Framework for functional testing, regression testing, GUI testing, data-driven and codeless testing of Desktop and Web applications. - Mocha, a popular web acceptance test framework based on Javascript and Node.js - Playwright (software) - Ranorex - Robot Framework - Selenium - Specification by example (Specs2) - Watir	2025-06-20T00:00:00
3,234	Archbishopric of Riga	The Archbishopric of Riga (Archiepiscopatus Rigensis, Erzbisdom Riga) was a Catholic diocese and civil government in Medieval Livonia, subject to the Holy See. It was established in 1186 and ended in 1561. ## History The diocese was established in 1186 as the Bishopric of Livonia at Ikšķile; after its seat was moved to Riga, it became the Bishopric of Riga in 1202 and was elevated to an archbishopric in 1255. The archbishops of Riga were also the secular rulers of Riga until 1561 when during the Reformation the territory converted from Catholicism to Lutheranism and all church territories were secularized. The see was restored as a diocese of the Catholic Church in 1918 and raised into an archdiocese in 1923. ## Bishops and Archbishops of Riga {#bishops_and_archbishops_of_riga} +------------------------+ \| Bishopric of Livonia\ \| \| (Bishopric of Üxküll)\ \| \| 1186--1255 \| +========================+ \| 1186--1196 \| +------------------------+ \| 1196--1198 \| +------------------------+ \| 1199--1202 \| +------------------------+ \| Bishopric of Riga\ \| \| 1202--1255 \| +------------------------+ \| 1202--1229 \| +------------------------+ \| 1229--1253 \| +------------------------+ \| 1245--1255 \| +------------------------+ \| Archbishopric of Riga\ \| \| 1255--1561 \| +------------------------+ \| 1255--1273 \| +------------------------+ \| 1273--1284 \| +------------------------+ \| 1285--1294 \| +------------------------+ \| 1294--1300 \| +------------------------+ \| 1300--1302 \| +------------------------+ \| 1303--1310 \| +------------------------+ \| 1304--1341 \| +------------------------+ \| 1341--1347 \| +------------------------+ \| 1348--1369 \| +------------------------+ \| 1370--1374 \| +------------------------+ \| 1374--1393 \| +------------------------+ \| 1393--1418 \| +------------------------+ \| 1418--1424 \| +------------------------+ \| 1424--1448 \| +------------------------+ \| 1448--1479 \| +------------------------+ \| 1479--1484 \| +------------------------+ \| 1484--1509 \| +------------------------+ \| 1509--1524 \| +------------------------+ \| 1524--1527 \| +------------------------+ \| 1528--1539 \| +------------------------+ \| 1539--1563 \| +------------------------+ A new Bishopric of Livonia was established in Latgalia in 1621 during the Inflanty Voivodeship of the Polish--Lithuanian Commonwealth. ## Coinage The Archbishops of Riga were innovators in the field of minting currency, reviving techniques abandoned since the collapse of Rome. The names of individual archbishops after 1418, as well as the years of their respective reigns, are stamped on Livonian pennies excavated at archaeological sites. In many cases, this is the only biographical data available. No Livonian pennies before 1418 have been found.	2025-06-20T00:00:00
3,235	Albert Frederick, Duke of Prussia	Albert Frederick (Albrecht Friedrich; Albrecht Fryderyk; 7 May 1553 -- 27 August 1618) was the Duke of Prussia, from 1568 until his death. He was a son of Albert of Prussia and Anna Marie of Brunswick-Lüneburg. He was the second and last Prussian duke of the Ansbach branch of the Hohenzollern family. ## Duke of Prussia {#duke_of_prussia} Albert became Duke of Prussia after paying feudal homage to his cousin, the King of Poland, Sigismund Augustus, on 19 July 1569 in Lublin. The homage was described by the Polish chronicler Jan Kochanowski in his work Proporzec (\"Standard\"). During the 1573 Polish election, Albert Frederick attempted to gain acceptance to the Polish senate but was opposed by the powerful Jan Zamoyski (later Grand Hetman of the Crown of the Kingdom of Poland) who feared the influence of Protestants in the Polish legislative body. Albert Frederick initially refused to recognize the election of Stefan Bathory and supported the candidacy of Maximilian of Austria. However, at the Toruń sejm of October 1576 he gave his support to the new monarch. As the great-grandson of the Polish king Casimir IV Jagiellon, and as a Duke in Prussia who was fluent in Polish, Albert Frederick was seriously considered for a time as a possible candidate for the Polish throne. He particularly enjoyed the support of Polish Lutherans. In 1572 he began to exhibit signs of mental disorder. He had twice tried to commit suicide and was prone to violent outbursts and held a great fear of \" Turks and Muscovites \" overrunning Germany. In early 1578, the regency was taken over by his cousin, George Frederick of Brandenburg-Kulmbach (1539--1603). After George Frederick\'s death in 1603, the Polish king Sigismund III Vasa appointed Joachim Frederick as regent in 1605, and permitted his son, John Sigismund, to succeed him in 1611. The latter became Duke of Prussia after Albert Frederick\'s death in 1618. ## Marriage Albert Frederick was married in 1573 to Marie Eleonore of Cleves, a daughter of Wilhelm, Duke of Jülich-Cleves-Berg and Archduchess Maria of Austria (1531--1581). Maria was a daughter of Ferdinand I, Holy Roman Emperor and Anna of Bohemia and Hungary. ## Issue Albert Frederick and Marie were parents to seven children: 1. Anna of Prussia (3 July 1576 -- 30 August 1625). Married John Sigismund, Elector of Brandenburg. 2. Marie of Prussia (23 January 1579 -- 21 February 1649). Married Christian, Margrave of Brandenburg-Bayreuth. 3. Albert Frederick of Prussia (1 June 1580 -- 8 October 1580) died in infancy. 4. Sophie of Prussia (31 March 1582 -- 4 December 1610). Married Wilhelm Kettler of Courland. 5. Eleanor of Prussia (21 August 1583 -- 9 April 1607). Married Joachim Frederick, Elector of Brandenburg. 6. Wilhelm Frederick of Prussia (23 June 1585 -- 18 January 1586) died in infancy. 7. Magdalene Sibylle of Prussia (31 December 1586 -- 22 February 1659). Married John George I, Elector of Saxony. At his death, the duchy passed to his son-in-law John Sigismund, Margrave of Brandenburg, combining the two territories under a single dynasty and forming Brandenburg-Prussia. ## Ancestors	2025-06-20T00:00:00
3,236	Ansbach	Ansbach (`{{IPAc-en\|ˈ\|æ\|n\|z\|b\|æ\|k}}`{=mediawiki} `{{respell\|ANZ\|bak}}`{=mediawiki}, `{{IPA\|de\|ˈansbax\|lang\|De-Ansbach.ogg}}`{=mediawiki}; Anschba) is a city in the German state of Bavaria. It is the capital of the administrative region of Middle Franconia. Ansbach is 25 mi southwest of Nuremberg and 90 mi north of Munich, on the river Fränkische Rezat, a tributary of the river Main. In 2020, its population was 41,681. Developed in the 8th century as a Benedictine monastery, it became the seat of the Hohenzollern family in 1331. In 1460, the Margraves of Brandenburg-Ansbach lived here. The city has a castle known as Margrafen--Schloss, built between 1704 and 1738. It was not badly damaged during the World Wars and hence retains its original historical baroque sheen. Ansbach is now home to a US military base and to the Ansbach University of Applied Sciences. The city has connections via autobahn A6 and highways B13 and B14. Ansbach station is on the Nürnberg--Crailsheim and Treuchtlingen--Würzburg railways and a Station of line S4 of the Nuremberg S-Bahn. ## Name origin {#name_origin} Ansbach was originally called Onoltesbach (about 790 AD), a term composed of three parts. The individual word elements are \"Onold\" (the city founder\'s name), the Suffix \"-es\" (a possessive ending, like \"-\'s\" in English) and the Old High German expression \"pah\" or \"bach\" (for brook). The name of the city has slightly changed throughout the centuries into Onoltespah (837 AD), Onoldesbach (1141 AD), Onoldsbach (1230 AD), Onelspach (1338 AD), Onsbach (1508 AD) and finally Ansbach (1732 AD). It was also formerly known as Anspach. ## History According to folklore, towards the end of the 7th century a group of Franconian peasants and their families went up into the wilderness to found a new settlement. Their leader Onold led them to an area called the \"Rezattal\" (Rezat valley). This is where they founded the \"Urhöfe\" (meaning the first farms: Knollenhof, Voggenhof and Rabenhof). Gradually more settlers, such as the \"Winden-Tribe\" came, and the farms grew into a small village. Many villages around Ansbach were founded by the \"Winden\" during that period (even today, their settlements can easily identified by their names, like Meinhardswinden, Dautenwinden or Brodswinden). A Benedictine monastery was established there around 748 by the Frankish noble St Gumbertus. The adjoining village of Onoltesbach was first noticed as a proper town in 1221. The counts of Öttingen ruled over Ansbach until the Hohenzollern burgrave of Nürnberg took over in 1331. The Hohenzollerns made Ansbach the seat of their dynasty until their acquisition of the Margraviate of Brandenburg in 1415. After the 1440 death of Frederick I, a cadet branch of the family established itself as the margraves of Ansbach. George the Pious introduced the Protestant Reformation to Ansbach in 1528, leading to Gumbertus Abbey\'s secularization in 1563. The Markgrafenschloß was built between 1704 and 1738. Its gardens continued to be a notable attraction into the 1800s. In 1791, the last margrave sold his realm to the Kingdom of Prussia. In 1796, the Duke of Zweibrücken, Maximilian Joseph --- the future Bavarian king--- was exiled to Ansbach the French took Zweibrücken. In Ansbach, Maximilian von Montgelas wrote an elaborate concept for the future political organization of Bavaria, which is known as the Ansbacher Mémoire. Napoleon forced Prussia to cede Ansbach and its principality to Bavaria in the Franco-Prussian treaty of alliance signed at Schönbrunn Palace on 15 December 1805 at the end of the Third Coalition. Ansbach became the capital of the \[\[Rezatkreis\]\] (\'Circle of the Rezat\'). Bavarian ownership was confirmed by the 1815 Congress of Vienna; Prussia was compensated with the Bavarian Duchy of Berg. In 1837 the Rezatkreis became the circle of Middle Franconia. Following the unification of Germany Ansbach had a population of 12,635. Jewish families were resident in Ansbach from at least the end of the 18th century. They set up a Jewish Cemetery in the Ruglaender Strasse, which was vandalised and razed under the Nazi regime in the Kristallnacht. It was repaired in 1946, but it was damaged several times more. A plaque on the wall of the cemetery commemorates these events. The Jewish Congregation built its synagogue at No 3 Rosenbadstrasse, but it too was damaged by the SA, though it was not burnt down for fear of damaging the neighbouring buildings. It serves today as a \"Symbolic House of God\". A plaque in the entrance serves as a memorial to the synagogue and to Jewish residents who were murdered during the Holocaust. In 1940, at least 500 patients were deported from the Heil- und Pflegeanstalt Ansbach \[Ansbach Medical and Nursing Clinic\] to the extermination facilities Sonnenstein and Hartheim which were disguised as psychiatric institutions, as part of the Action T4 euthanasia action. They were gassed there. At the clinic in Ansbach itself, around 50 intellectually disabled children were injected with the drug Luminal and killed that way. A plaque was erected in their memory in 1988 in the local hospital at No. 38 Feuchtwangerstrasse. During World War II, a subcamp of Flossenbürg concentration camp was located here. Also during the Second World War the Luftwaffe and Wehrmacht had bases here. The nearby airbase was the home station for the Stab & I/KG53 (Staff & 1st Group of Kampfgeschwader 53) operating 38 Heinkel He 111 bombers. On 1 September 1939 this unit was one of the many that participated in the attack on Poland that started the war. All of its bridges were destroyed during the course of the war. During the Western Allied invasion of Germany in April 1945, the airfield was seized by the United States Third Army, and used by the USAAF 354th Fighter Group which flew P-47 Thunderbolts from the aerodrome (designated ALG R-82) from late April until the German capitulation on 7 May 1945. At the end of the war, 19-year-old student Robert Limpert tried to get the town to surrender to the US Forces without a fight. He was betrayed by Hitler Youth and was hanged from the portal of the City Hall by the city\'s military commander, Col. (Oberst) Ernst Meyer. Several memorials to his heroic deed have been erected over the years, despite opposition from some residents --- in the Ludwigskirche, in the Gymnasium Carolinum and at No 6 Kronenstrasse. After the Second World War, Ansbach belonged to the American Zone. The American Military authorities established a displaced persons (DP) camp in what used to be a sanatorium in what is today the Strüth quarter. Bachwoche Ansbach has been held in Ansbach since 1947. Since 1970, Ansbach has enlarged its municipal area by incorporating adjacent communities. Ansbach hosts several units of the U.S. armed forces, associated with German units under NATO. There are five separate U.S. installations: Shipton Kaserne, home to 412th Aviation Support Battalion, Katterbach Kaserne, formerly the home of the 1st Infantry Division\'s 4th Combat Aviation Brigade, also home of 501st M.I. Bn and 501st Avn Bn. which has been replaced by the 12th Combat Aviation Brigade as of 2006, as part of the 1st Infantry Division\'s return to Fort Riley, Kansas; Bismarck Kaserne, which functions as a satellite post to Katterbach, hosting their Post Theater, barracks, Von Steuben Community Center, Military Police, and other support agencies, Barton Barracks, home to the USAG Ansbach and Bleidorn Barracks, which has a library and housing, and Urlas, which hosts the Post Exchange as well as a housing area opened in 2010. Ansbach was also home to the headquarters of the 1st Armored Division (United States) from 1972 to the early 1990s. On 24 July 2016 a bomb was detonated in a restaurant in the city, killing only the bomber himself and injuring few people. The perpetrator was reported to be a Syrian refugee whose asylum application had been rejected but who had been given exceptional leave to remain until the security situation in Syria returned to a safe condition. Witnesses reported he had tried to enter a nearby music festival but had been turned away, before detonating his device outside a nearby wine bar. ## Boroughs - Eyb bei Ansbach, part of Ansbach since 1 October 1970 - Bernhardswinden, part of Ansbach since 1 July 1972 - Brodswinden, part of Ansbach since 1 July 1972 - Claffheim, part of Ansbach since 1 July 1972 - Elpersdorf bei Ansbach, part of Ansbach since 1 July 1972 - Hennenbach, part of Ansbach since 1 July 1972 - Neuses bei Ansbach, part of Ansbach since 1 July 1972 - Strüth - Wasserzell - Schalkhausen, part of Ansbach since 1 July 1972 - Geisengrund - Dornberg - Neudorf - Steinersdorf ## Lord mayors {#lord_mayors} - 1877--1905: Ludwig Keller (1839--1911) - 1905--1919: Ernst Rohmeder - 1919--1934: Wilhelm Borkholder (1886--1945) - 1934--1945: Richard Hänel (NSDAP) (1895-date of death unknown) - 1945: Hans Schregle (1890--1970), (SPD), introduced by the Office of Military Government, United States - 1945--1950: Ernst Körner (SPD) - 1950--1952: Friedrich Böhner - 1952--1957: Karl Burkhardt (CSU) - 1957--1971: Ludwig Schönecker (CSU) - 1971--1990: Ernst-Günther Zumach (CSU) (1926--2012) - 1990--2008: Ralf Felber (SPD) - 2008-2020: Carda Seidel (independent) - since May 2020: Thomas Deffner (CSU) ## Sights - Castle of the Margraves of Brandenburg-Ansbach - Museum Retti Palais - Margrave museum - Kaspar Hauser Monument - St. Gumbertus and St. Johannis churches, both 15th century - Theater Ansbach - Ansbacher Kammerspiele - LOFT -- projectspace for contemporary art ## Climate Ansbach has a transitional temperate-continental climate (Köppen climate classification: Cfb/Dfb), with a small diurnal air temperature variation between day and night during winter, and with a moderate annual precipitation. ## Demography ## Economy Around the time of the unification of Germany in 1871, the chief manufactures of Ansbach were woollen, cotton, and half-silk goods; earthenware; tobacco; cutlery; and playing cards. A considerable trade in grain, wool, and flax was also supported. By the onset of the First World War, it also produced machinery, toys, and embroidery. Today there is a large density of plastics industry in the city and rural districts around Ansbach. The city is known for making Peperami pork sausages and jerky. ## Transport Ansbach lies on the Treuchtlingen-Würzburg railway. ## Notable people {#notable_people} ### Public service {#public_service} - Elisabeth von Brandenburg-Ansbach (1451--1524), Princess of Brandenburg, by marriage Duchess of Württemberg - Frederick I, Margrave of Brandenburg-Ansbach (1460--1536), Margrave of Ansbach & Margrave of Kulmbach - Albert, Duke of Prussia (1490--1568), Grand Master of the Teutonic Order and the first duke of Prussia. - Margravine Eleonore Juliane of Brandenburg-Ansbach (1663--1724), Princess of Brandenburg-Ansbach, by marriage Duchess of Württemberg-Winnental - Caroline of Ansbach (1683--1737), Queen of Great Britain and Ireland, wife of George II of Great Britain. - Christian Friedrich Carl Alexander (1736--1806), the last Margrave of Ansbach - Karl Heinrich Ritter von Lang (1764--1835), a historian and statesman, lived mainly in Ansbach. - Moritz Ritter von Spies (1805--1862), Bavarian Major General and War Minister - John James Maximilian Oertel (1811--1882), a Lutheran clergyman, converted to Roman Catholicism and moved to the United States - Maximilian Wolfgang Duncker (1811--1886), a historian and politician, died in Ansbach. - Kaspar Hauser (1812--1833), lived in Ansbach from 1830 to 1833, stabbed in the palace gardens - Henry Hochheimer (1818--1912), rabbi - George H. Brickner (1834--1904), U.S. Representative from Wisconsin - Pinchas Kohn (1867--1941), was the last rabbi of Ansbach. He was the rabbinical advisor to the German occupying forces of Poland in the First World War and was also one of the founders of the World Agudath Israel movement - Theodor Endres (1876--1956), General of the Artillery - Wilhelm Adam (1893--1978), Colonel General - Hermann Fegelein (1906--1945), General of the Waffen-SS, was married to the sister of Eva Braun - Waldemar Fegelein (1912--2000), officer in the Waffen-SS - Amélie Jakobovits (née Munk, 1928--2010), wife of Immanuel Jakobovits, Chief Rabbi of the United Kingdom - Walter Brandmüller (born 1929), theologian and historian, president of the Pontifical Committee for Historical Sciences - Manfred Ach (born 1940), politician, from 1994 to 2008 Member of the Bavarian Parliament ### Arts & science {#arts_science} - Leonhart Fuchs (1501--1566), botanist and physician to margrave Georg Friedrich - Simon Marius (1573--1625), astronomer lived in Ansbach, he observed Jupiter\'s moons from the castle\'s tower, which led to a dispute with the true discoverer, Galileo Galilei - Georg Ernst Stahl (1659--1734), chemist, physician and metallurgist. - Matthias Buchinger (1674--1740), a German artist, magician and illustrator, born without hands or legs - Johann Uz (1720--1796), a German poet. - Marcus Eliezer Bloch (1723--1799), ichthyologist. - Georg Christian Oeder (1728--1791), pre-Linnean botanist - Ludwig von Förster (1792--1863), architect: Ringstrasse, 3 & synagogues in Vienna and Budapest - August von Platen-Hallermünde (1796--1835), poet. - Georges Oberhaeuser (1798--1868), optician - Oskar Freiherr von Redwitz (1823--1891), a poet from nearby Lichtenau. - Ferdinand Christian Gustav Arnold (1828--1901), lichenologist and taxonomist - Wilhelm Hecht (1843--1920), wood engraver and etcher - Fritz Hommel (1854--1936), orientalist - Theodor Escherich (1857--1911), pediatrician and bacteriologist - Max Westenhöfer (1871--1957), pathologist, professor at the University of Berlin and the University of Chile. Proposed the Aquatic ape hypothesis - Herbert Blendinger (1936--2020), violinist and composer ### Sport - Helga Matschkur (born 1943), gymnast, competed in six events at the 1968 Summer Olympics. - Georg Volkert (1945--2020), footballer, played 410 games in Bundesliga and won 12 caps for West Germany - Sebastian Preiss (born 1981), handball player - Dominik Farnbacher (born 1984), racing driver - Alex King (born 1985), basketball player - Mario Farnbacher (born 1992), racing driver - Danilo Dittrich (born 1995), football player ## Twin towns -- sister cities {#twin_towns_sister_cities} Ansbach is twinned with: - Anglet, Nouvelle-Aquitaine, France - Bay City, Michigan, United States - Fermo, Marche, Italy - Jingjiang, Jiangsu, China ## In popular culture {#in_popular_culture} In the novel The Schirmer Inheritance (1953) by Eric Ambler (1909--1998), Sergeant Franz Schirmer of the Ansbach Dragoons is wounded in the battle of Preussisch-Eylau in 1807. He returns to Ansbach to settle but changes his name as he has been posted as a deserter. The bulk of the novel concerns efforts by an American law firm to trace his descendants to claim an inheritance.	2025-06-20T00:00:00
3,250	Amblypoda	Amblypoda was a taxonomic hypothesis uniting a group of extinct, herbivorous mammals. They were considered a suborder of the primitive ungulate mammals and have since been shown to represent a polyphyletic group. ## Characteristics The Amblypoda take their name from their short and stumpy feet, which were furnished with five toes each and supported massive pillar-like limbs. The brain cavity was extremely small and insignificant in comparison to the bodily mass, which was equal to that of the largest rhinoceroses. These animals were descendants of the small ancestral ungulates that retained all the primitive characteristics of the latter, accompanied by a huge increase in body size. The Amblypoda were confined to the Paleocene and Eocene periods and occurred in North America, Asia (especially Mongolia) and Europe. The cheek teeth were short-crowned (brachyodont), with the tubercles more-or-less completely fused into transverse ridges, or cross-crests (lophodont type), and the total number of teeth was in one case the typical 44, but in another was fewer. The vertebra of the neck unite on nearly flat surfaces, the humerus had lost the foramen, or perforation, at the lower end, and the third trochanter to the femur may have also been wanting. In the forelimb, the upper and lower series of carpal (finger) bones scarcely alternated, but in the hind foot, the astragalus overlapped the cuboid, while the fibula, which was quite distinct from the tibia (as was the radius from the ulna in the forelimb), articulated with both astragalus and calcaneum. ## Types of amblypods {#types_of_amblypods} The most generalized type was Coryphodon, representing the family Coryphodontidae, from the lower Eocene of Europe and North America, in which there were 44 teeth and no horn-like excrescences on the long skull, while the femur had a third trochanter. The canines were somewhat elongated and were followed by a short gap in each jaw, and the cheek-teeth were adapted for succulent food. The length of the body reached about six feet in some cases. In the middle Eocene formations of North America occurred the more specialized Uintatherium (or Dinoceras), typifying the family Uintatheriidae. Uintatheres were huge creatures with long narrow skulls, of which the elongated facial portion carried three pairs of bony horn-cores, probably covered with short horns in life, the hind-pair having been much the largest. The dental formula was i. 0/3, c. 1/1, p. 3/3·4, m. 3/3, the upper canines having been long sabre-like weapons, protected by a descending flange on each side of the lower front jaw. In the basal Eocene of North America, the Amblypoda were represented by extremely primitive, five-toed, small ungulates such as Periptychus and Pantolambda, each of these typifying a family`{{Vague\|date=April 2009}}`{=mediawiki}. The full typical series of 44 teeth was developed in each, but whereas in the Periptychidae, the upper molars were bunodont and tritubercular, in the Pantolambdidae, they had assumed a selenodont structure. Creodont characters were displayed in the skeleton. ## Current taxonomy of animals once classified in Amblypoda {#current_taxonomy_of_animals_once_classified_in_amblypoda} Few authorities recognize Amblypoda in modern classifications. The following mammals were once considered part of this group: - Order Pantodonta - Family Wangliidae - Family Harpyodidae - Family Bemalambdidae - Family Pastoralodontidae - Family Titanoideidae - Family Pantolambdidae (including Pantolambda) - Family Barylambdidae - Family Cyriacotheriidae - Family Pantolambdodontidae - Family Coryphodontidae (including Coryphodon) - Order Dinocerata - Family Uintatheriidae (includes Uintatherium, Eobasileus, Tetheopsis, etc. Gobiatherium is sometimes placed in its own family.) - a part of the order Condylarthra, mainly the family Periptychidae (including Periptychus)	2025-06-20T00:00:00
3,251	Amblygonite	Amblygonite (`{{IPAc-en\|æ\|m\|ˈ\|b\|l\|ɪ\|ɡ\|ə\|ˌ\|n\|aɪ\|t}}`{=mediawiki}) is a fluorophosphate mineral, `{{chem2\|(Li,Na)AlPO4(F,OH)}}`{=mediawiki}, composed of lithium, sodium, aluminium, phosphate, fluoride and hydroxide. The mineral occurs in pegmatite deposits and is easily mistaken for albite and other feldspars. Its density, cleavage and flame test for lithium are diagnostic. Amblygonite forms a series with montebrasite, the low fluorine endmember. Geologic occurrence is in granite pegmatites, high-temperature tin veins, and greisens. Amblygonite occurs with spodumene, apatite, lepidolite, tourmaline, and other lithium-bearing minerals in pegmatite veins. It contains about 10% lithium, and has been utilized as a source of lithium. The chief commercial sources have historically been the deposits of California and France. ## History The mineral was first discovered in Saxony by August Breithaupt in 1817, and named by him from the Greek amblus, blunt, and gonia, angle, because of the obtuse angle between the cleavages. Later it was found at Montebras, Creuse, France, and at Hebron in Maine; and because of slight differences in optical character and chemical composition the names montebrasite and hebronite have been applied to the mineral from these localities.The term amblygonite has been used interchangeably in mining, whether this mineral or montebrasite was extracted. In fact, montebrasite is much more common than amblygonite, which is a rare mineral. It has been discovered in considerable quantity at Pala in San Diego county, California; Caceres, Spain; and the Black Hills of South Dakota. A blue form of amblygonite-montebrasite has been described from Rwanda. The largest documented single crystal of amblygonite measured 7.62 × 2.44 × 1.83 m and weighed about 102 tons. ## Gemology Transparent amblygonite has been faceted and used as a gemstone. As a gemstone set into jewelry it is vulnerable to breakage and abrasion from general wear, as its hardness and toughness are poor. The main sources for gem material are Brazil and the United States. Australia, France, Germany, Namibia, and Norway, and Spain have also produced gem quality amblygonite. `{{Clear left}}`{=mediawiki}	2025-06-20T00:00:00

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