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https://en.wikipedia.org/wiki/Bernhard%20von%20Lindenau
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Baron Bernhard August von Lindenau (11 June 1779 – 21 May 1854) was a German lawyer, astronomer, politician, and art collector.
Lindenau was born in Altenburg, the son of Johann August Lindenau, a regional administrator (Landschaftsdirektor). In 1793, Lindeau began studying law and mathematics at Leipzig, and beginning in 1801 he worked at the astronomical observatory in Seeburg. In 1830 he was the Minister of the Interior during a turbulent period in the history of Saxony. Late in the year he oversaw measures to calm violent protests demanding political reform. From 1831 to 1843 he was Minister-President.
He created a collection of Italian artwork from the 14th and 15th centuries by Florentine painters in an effort to create artistic awareness. He gave his art collection to the city of Altenburg on the condition that they create a museum to display the pieces. This museum was finished in 1875, and became the Lindenau-Museum.
Lindenau edited the Monatliche Correspondenz zur Beförderung der Erd- und Himmels-Kunde starting in 1807. The Journal was founded by Franz Xaver von Zach in 1800 and existed until 1813.
In 1809 he became correspondent of the Royal Institute of the Netherlands, when that became the Royal Netherlands Academy of Arts and Sciences in 1851 he joined as foreign member. Lindenau was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1822.
He died in Windischleuba.
Awards and honors
Asteroid 9322 Lindenau was named for him.
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https://en.wikipedia.org/wiki/William%20Thompson%20%28naturalist%29
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William Thompson (2 December 1805 – 17 February 1852) was an Irish naturalist celebrated for his founding studies of the natural history of Ireland, especially in ornithology and marine biology. Thompson published numerous notes on the distribution, breeding, eggs, habitat, song, plumage, behaviour, nesting and food of birds. These formed the basis of his four-volume The Natural History of Ireland, and were much used by contemporary and later authors such as Francis Orpen Morris.
Early years
Thompson was born in the booming maritime city of Belfast, Ireland, the eldest son of a linen merchant, whose wealth would later permit Thompson to fund his own research without an academic affiliation. Thompson attended the newly formed Royal Belfast Academical Institution, where he got a degree in Biological Science. Founded by, amongst others, John Templeton, the school had a strong natural history section that produced a cohort of prominent naturalists. In 1826 he went on a Grand Tour accompanied by cousin George Langtry, a Fortwilliam, Belfast shipowner. They starting in the Netherlands then travelled through Belgium down the Rhine to Switzerland and on to Rome and Naples. They returned via Florence, Geneva and Paris. Thompson's first scientific paper, The Birds of the Copeland Islands, was published in 1827 shortly after he joined the Belfast Natural History Society. In these years he became a member of the Belfast Literary Society.
Personal life
William Thompson was a man of r
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https://en.wikipedia.org/wiki/Matter%20creation
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Even restricting the discussion to physics, scientists do not have a unique definition of what matter is. In the currently known particle physics, summarised by the standard model of elementary particles and interactions, it is possible to distinguish in an absolute sense particles of matter and particles of antimatter. This is particularly easy for those particles that carry electric charge, such as electrons, protons or quarks, while the distinction is more subtle in the case of neutrinos, fundamental elementary particles that do not carry electric charge. In the standard model, it is not possible to create a net amount of matter particles—or more precisely, it is not possible to change the net number of leptons or of quarks in any perturbative reaction among particles. This remark is consistent with all existing observations.
However, similar processes are not considered to be impossible and are expected in other models of the elementary particles, that extend the standard model. They are necessary in speculative theories that aim to explain the cosmic excess of matter over antimatter, such as leptogenesis and baryogenesis. They could even manifest themselves in laboratory as proton decay or as creations of electrons in the so-called neutrinoless double beta decay. The latter case occurs if the neutrinos are Majorana particles, being at the same time matter and antimatter, according to the definition given just above.
In a wider sense, one can use the word matter simpl
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https://en.wikipedia.org/wiki/Internal%20conversion%20%28chemistry%29
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Internal conversion is a transition from a higher to a lower electronic state in a molecule or atom. It is sometimes called "radiationless de-excitation", because no photons are emitted. It differs from intersystem crossing in that, while both are radiationless methods of de-excitation, the molecular spin state for internal conversion remains the same, whereas it changes for intersystem crossing.
The energy of the electronically excited state is given off to vibrational modes of the molecule. The excitation energy is transformed into heat.
Examples
A classic example of this process is the quinine sulfate fluorescence, which can be quenched by the use of various halide salts. The excited molecule can de-excite by increasing the thermal energy of the surrounding solvated ions.
Several natural molecules perform a fast internal conversion. This ability to transform the excitation energy of photon into heat can be a crucial property for photoprotection by molecules such as melanin. Fast internal conversion reduces the excited state lifetime, and thereby prevents bimolecular reactions. Bimolecular electron transfer always produces a reactive chemical species, free radicals. Nucleic acids (precisely the single, free nucleotides, not those bound in a DNA/RNA strand) have an extremely short lifetime due to a fast internal conversion.
Both melanin and DNA have some of the fastest internal conversion rates.
In applications that make use of bimolecular electron transfer the internal
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https://en.wikipedia.org/wiki/August%20Toepler
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August Joseph Ignaz Toepler (7 September 1836 – 6 March 1912) was a German chemist and physicist known for his experiments in electrostatics.
Biography
August Toepler was born on 7 September 1836. He studied chemistry at the Gewerbe-Institut Berlin (1855–1858) and graduated from the University of Jena in 1860. Later Toepler turned to experimental physics. August Toepler was a lecturer of chemistry and physics at the Academy Poppelsdorf (1859-1864). He received a chair of chemistry and chemical technology at the Polytechnic Institute of Riga and he hold this position between 1864 and 1868.
In 1864, he applied Foucault's knife-edge test for telescope mirrors to the analysis of fluid flow and the shock wave. He named this new method schlieren photography, for which he is justifiably famous. He also developed the Toepler machine, an electrostatic influence machine (high voltage generator) in 1865, which would one day find use in early medical x-ray machines. Improved versions were produced by Wilhelm Holtz, Roger and J. Robert Voss.
In 1868, he became a professor at the University of Graz in Austria, where under his administration a new physical institute has appeared. In 1876, Toepler came to Dresden where he was offered the chair of Experimental Physics. He was a director of the Physical Institute at the Dresden Technical University till his retirement in 1900. His son Maximilian Toepler continued the scientific work independently. Toepler is remembered as an inventor of
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https://en.wikipedia.org/wiki/Physics%20Today
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Physics Today is the membership magazine of the American Institute of Physics. First published in May 1948, it is issued on a monthly schedule, and is provided to the members of ten physics societies, including the American Physical Society. It is also available to non-members as a paid annual subscription.
The magazine informs readers about important developments in overview articles written by experts, shorter review articles written internally by staff, and also discusses issues and events of importance to the science community in politics, education, and other fields. The magazine provides a historical resource of events associated with physics. For example it discussed debunking the physics of the Star Wars program of the 1980s, and the state of physics in China and the Soviet Union during the 1950s and 1970s.
According to the Journal Citation Reports, the journal has a 2017 impact factor of 4.370.
References
External links
Archival collections
AIP Physics Today Division miscellaneous publications, 1955-2006, Niels Bohr Library & Archives
AIP Physics Today Division records of Irwin Goodwin, 1983-1993, Niels Bohr Library & Archives
AIP Physics Today Division records, 1948-1971, Niels Bohr Library & Archives
AIP Physics Today division Bertram Schwarzschild Nobel Prize files, 1954-2013, Niels Bohr Library & Archives
American Institute of Physics academic journals
Monthly magazines published in the United States
Science and technology magazines published in the U
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https://en.wikipedia.org/wiki/Bismuth%28III%29%20oxide
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Bismuth(III) oxide is perhaps the most industrially important compound of bismuth. It is also a common starting point for bismuth chemistry. It is found naturally as the mineral bismite (monoclinic) and sphaerobismoite (tetragonal, much more rare), but it is usually obtained as a by-product of the smelting of copper and lead ores. Dibismuth trioxide is commonly used to produce the "Dragon's eggs" effect in fireworks, as a replacement of red lead.
Structure
The structures adopted by differ substantially from those of arsenic(III) oxide, , and antimony(III) oxide, .
Bismuth oxide, has five crystallographic polymorphs. The room temperature phase, α- has a monoclinic crystal structure. There are three high temperature phases, a tetragonal β-phase, a body-centred cubic γ-phase, a cubic δ- phase and an ε-phase.
The room temperature α-phase has a complex structure with layers of oxygen atoms with layers of bismuth atoms between them. The bismuth atoms are in two different environments which can be described as distorted 6 and 5 coordinate respectively.
β- has a structure related to fluorite.
γ- has a structure related to that of sillenite (), but in which a small fraction of the bismuth atoms occupy positions occupied by silicon atoms in sillenite, so the formula may be written as . The crystals are chiral (space group I23, or no. 197) with two formulas per unit cell.
δ- has a defective fluorite-type crystal structure in which two of the eight oxygen sites in the unit cell a
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https://en.wikipedia.org/wiki/Algebra%20of%20physical%20space
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In physics, the algebra of physical space (APS) is the use of the Clifford or geometric algebra Cl3,0(R) of the three-dimensional Euclidean space as a model for (3+1)-dimensional spacetime, representing a point in spacetime via a paravector (3-dimensional vector plus a 1-dimensional scalar).
The Clifford algebra Cl3,0(R) has a faithful representation, generated by Pauli matrices, on the spin representation C2; further, Cl3,0(R) is isomorphic to the even subalgebra Cl(R) of the Clifford algebra Cl3,1(R).
APS can be used to construct a compact, unified and geometrical formalism for both classical and quantum mechanics.
APS should not be confused with spacetime algebra (STA), which concerns the Clifford algebra Cl1,3(R) of the four-dimensional Minkowski spacetime.
Special relativity
Spacetime position paravector
In APS, the spacetime position is represented as the paravector
where the time is given by the scalar part , and e1, e2, e3 are the standard basis for position space. Throughout, units such that are used, called natural units. In the Pauli matrix representation, the unit basis vectors are replaced by the Pauli matrices and the scalar part by the identity matrix. This means that the Pauli matrix representation of the space-time position is
Lorentz transformations and rotors
The restricted Lorentz transformations that preserve the direction of time and include rotations and boosts can be performed by an exponentiation of the spacetime rotation biparavector W
In
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https://en.wikipedia.org/wiki/Brian%20Swimme
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Brian Thomas Swimme (born 1950) is a professor at the California Institute of Integral Studies, in San Francisco, where he teaches evolutionary cosmology to graduate students in the philosophy, cosmology, and consciousness program. He received his Ph.D. (1978) from the department of mathematics at the University of Oregon for work with Richard Barrar on singularity theory, with a dissertation titled Singularities in the N-Body Problem.
Swimme's published work portrays the 14-billion-year trajectory of cosmogenesis "as a spellbinding drama, full of suspense, valor, tragedy, and celebration". His work includes The Universe is a Green Dragon (1984), The Universe Story, written with Thomas Berry (1992), The Hidden Heart of the Cosmos (1996), and The Journey of the Universe, written with Mary Evelyn Tucker (2011). Swimme is the producer of three DVD series: Canticle to the Cosmos (1990), The Earth's Imagination (1998), and The Powers of the Universe (2004). Swimme teamed with Mary Evelyn Tucker, David Kennard, Patsy Northcutt, and Catherine Butler to produce Journey of the Universe, a Northern California Emmy-winning film released in 2011. These works draw together scientific discoveries in astronomy, geology and biology, with humanistic insights concerning the nature of the universe.
Background
Swimme is an evolutionary cosmologist on the graduate faculty of the California Institute of Integral Studies in the philosophy, cosmology and consciousness and also ecology, spiritualit
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https://en.wikipedia.org/wiki/EXperimental%20Computing%20Facility
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Founded in 1986, the eXperimental Computing Facility (XCF) is an undergraduate computing-interest organization at University of California, Berkeley. The "Experimental" description was given in contrast to the Open Computing Facility and the Computer Science Undergraduate Association, which support most of the general-interest computing desires of the campus. As such, the XCF stands as a focus for a small group of computer-scientists uniquely interested in computer science.
Members of the organization have been involved in projects such as NNTP, GTK+, GIMP, Gnutella, and Viola. Members of the XCF were instrumental in defending against the Morris Internet worm.
Notable alumni
Notable alumni of the organization include:
Jonathan Blow, Gene Kan, Spencer Kimball, Peter Mattis, Pei-Yuan Wei, and Phil Lapsley.
References
External links
University of California, Berkeley
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https://en.wikipedia.org/wiki/Natta%20projection
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In chemistry, the Natta projection (named for Italian chemist Giulio Natta) is a way to depict molecules with complete stereochemistry in two dimensions in a skeletal formula. In a hydrocarbon molecule with all carbon atoms making up the backbone in a tetrahedral molecular geometry, the zigzag backbone is in the paper plane (chemical bonds depicted as solid line segments) with the substituents either sticking out of the paper toward the viewer (chemical bonds depicted as solid wedges) or away from the viewer (chemical bonds depicted as dashed wedges). The Natta projection is useful for representing the tacticity of a polymer.
See also
Structural formula
Wedge-and-dash notation in skeletal formulas
Haworth projection
Newman projection
Fischer projection
References
Eponymous diagrams of chemistry
Stereochemistry
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https://en.wikipedia.org/wiki/Vinyl%20polymer
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In polymer chemistry, vinyl polymers are a group of polymers derived from substituted vinyl () monomers. Their backbone is an extended alkane chain . In popular usage, "vinyl" refers only to polyvinyl chloride (PVC).
Examples
Vinyl polymers are the most common type of plastic. Important examples can be distinguished by the R group in the monomer H2C=CHR:
Polyethylene R = H
polypropylene from propylene, R = CH3
Polystyrene is made from styrene, R = C6H5
Polyvinyl chloride (PVC) is made from vinyl chloride, R= Cl
Polyvinyl acetate (PVAc) is made from vinyl acetate, R = O2CCH3
Polyacrylonitrile is made from acrylonitrile, R = CN
Production
Vinyl polymers are produced using catalysts. Ziegler–Natta catalysts are used commercially for production of polyethylene and polypropylene. Many are produced using radical initiators which are produced from organic peroxides. Still others (poystyrene) are produced using anionic initiators such as butyl lithium.
An exception from the usual rules, polyvinyl alcohol, )n, is produced by hydrolysis of polyvinyl acetate. Vinyl alcohol is not sufficiently stable to undergo polymerization.
Structure
Vinyl polymers are subject of several structural variations, which greatly expands the range of polymers and their applications.
With the exception of polyethylene, vinyl polymers can arise from head-to-tail linking of monomers, head-to-head combined with tail-to-tail, or a mixture of those two patterns. Additionally the substituted carbon
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https://en.wikipedia.org/wiki/James%20McLurkin
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James McLurkin (born 1972) is a Senior Hardware Engineer at Google. Previously, he was an engineering assistant professor at Rice University specializing in swarm robotics. In 2005, he appeared on an episode of PBS' Nova and is a winner of the 2003 Lemelson-MIT Prize.
Early life
McLurkin was born in 1972 in Baldwin, New York and graduated from Baldwin Senior High School in 1990. He built his first robot, Rover, in 1988.
Education and career
McLurkin completed his PhD in computer science in May 2008 at the Massachusetts Institute of Technology Computer Science and Artificial Intelligence Laboratory. Previously, he earned his master's degree in electrical engineering from the University of California at Berkeley and B.S. from MIT.
As part of his doctoral research, McLurkin developed algorithms and techniques for programming "swarms" of autonomous robots to mimic the behavior of bees, including their abilities to cluster, disperse, follow, and orbit.
In 1995, McLurkin was invited by the Smithsonian Institution to speak about his life and career in a presentation for schoolchildren sponsored by the Smithsonian's Lemelson Center for the Study of Invention and Innovation.
References
External links
Personal web page
NOVA Science NOW feature, includes video segment
Prototype Online: Inventive Voices podcast featuring a 2006 interview with James McLurkin - From the Smithsonian's Lemelson Center for the Study of Invention and Innovation website.
Lemelson–MIT Prize
1972 birt
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https://en.wikipedia.org/wiki/210%20%28number%29
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210 (two hundred [and] ten) is the natural number following 209 and preceding 211.
In mathematics
210 is a composite number, an abundant number, Harshad number, and the product of the first four prime numbers (2, 3, 5, and 7), and thus a primorial. It is also the least common multiple of these four prime numbers. It is the sum of eight consecutive prime numbers (13 + 17 + 19 + 23 + 29 + 31 + 37 + 41 = 210).
It is a triangular number (following 190 and preceding 231), a pentagonal number (following 176 and preceding 247), and the second smallest to be both triangular and pentagonal (the third is 40755).
It is also an idoneal number, a pentatope number, a pronic number, and an untouchable number. 210 is also the third 71-gonal number, preceding 418. It is the first primorial number greater than 2 which is not adjacent to 2 primes (211 is prime, but 209 is not).
It is the largest number n such that all primes between n/2 and n yield a representation as a sum of two primes.
Integers between 211 and 219
211
212
213
214
215
216
217
218
219
See also
210 BC
AD 210
North American telephone area code area code 210
References
Integers
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https://en.wikipedia.org/wiki/Plumbate
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In chemistry, a plumbate often refers to compounds that can be viewed as derivatives of the hypothetical anion. The term also refers to any anion of lead or any salt thereof. So the term is vague and somewhat archaic.
Examples
Halides
Salts of , , , etc. are labeled as iodoplumbates. Lead perovskite semiconductors are often described as plumbates.
Lead oxyanions
Plumbates are formed by the reaction of lead(IV) oxide, , with alkali. Plumbate salts contain either the hydrated hexahydroxoplumbate(IV) or plumbate anion , or the anhydrous anions (metaplumbate) or (orthoplumbate). For example, dissolving in a hot, concentrated aqueous solution of potassium hydroxide forms the potassium hexahydroxoplumbate(IV) salt . The anhydrous salts may be synthesized by heating metal oxides or hydroxides with .
The most widely discussed plumbates are derivatives of barium metaplumbate . When doped with some bismuth in place of lead, the material exhibits superconductivity at 13 K. At the time of this discovery, oxides did not show such properties. The surprise associated with this work was eclipsed by the advent of the cuprate superconductors.
Binary lead oxides
Lead tetroxide ("red lead"), a valence-mixed oxide with formula (red), may be thought of as lead(II) orthoplumbate(IV), . Lead sesquioxide, , is also known (reddish yellow), and has the structure of lead(II) metaplumbate(IV), .
References
External links
National Pollutant Inventory - Lead and Lead Compounds Fact Sheet
Lead
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https://en.wikipedia.org/wiki/Tin%28IV%29%20oxide
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Tin(IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO2. The mineral form of SnO2 is called cassiterite, and this is the main ore of tin. With many other names, this oxide of tin is an important material in tin chemistry. It is a colourless, diamagnetic, amphoteric solid.
Structure
Tin(IV) oxide crystallises with the rutile structure. As such the tin atoms are six coordinate and the oxygen atoms three coordinate. SnO2 is usually regarded as an oxygen-deficient n-type semiconductor.
Hydrous forms of SnO2 have been described as stannic acid. Such materials appear to be hydrated particles of SnO2 where the composition reflects the particle size.
Preparation
Tin(IV) oxide occurs naturally. Synthetic tin(IV) oxide is produced by burning tin metal in air. Annual production is in the range of 10 kilotons. SnO2 is reduced industrially to the metal with carbon in a reverberatory furnace at 1200–1300 °C.
Amphoterism
Although SnO2 is insoluble in water, it is amphoteric, dissolving in base and acid. "Stannic acid" refers to hydrated tin (IV) oxide, SnO2, which is also called "stannic oxide."
Tin oxides dissolve in acids. Halogen acids attack SnO2 to give hexahalostannates, such as [SnI6]2−. One report describes reacting a sample in refluxing HI for many hours.
SnO2 + 6 HI → H2SnI6 + 2 H2O
Similarly, SnO2 dissolves in sulfuric acid to give the sulfate:
SnO2 + 2 H2SO4 → Sn(SO4)2 + 2 H2O
SnO2 dissolves in strong bases to give "stannates," with th
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https://en.wikipedia.org/wiki/Benjamin%20W.%20Lee
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Benjamin Whisoh Lee (; January 1, 1935 – June 16, 1977), or Ben Lee, was a Korean- American theoretical physicist. His work in theoretical particle physics exerted great influence on the development of the standard model in the late 20th century, especially on the renormalization of the electro-weak model and gauge theory.
He predicted the mass of the charm quark and contributed to its search. His student Kang Joo-sang later became professor emeritus at the Department of Physics at Korea University. Lee is also the inspiration for the fictional character Lee Yong-hu in Kim Jin-myung's novel, The Rose of Sharon Blooms Again.
Biography
Lee was born in Yongsan, Seoul. Both of Lee's parents were trained as doctors, and he was the eldest of four siblings. His mother was the breadwinner of the household, and was initially employed as a doctor at a hospital. Later, she opened her own pediatrics and obstetrics/gynaecology practice.
Lee demonstrated academic promise as a child and gained admission to Kyunggi Middle School. During his fourth year, the Korean War broke out and his family was forced to evacuate to the Busan Perimeter, where he continued his schooling.
Lee later enrolled in Kyunggi High School, and one year before graduating, was admitted as the top-ranked student to Seoul National University as a chemical engineering major. While in college, he was awarded a scholarship by the association of military wives whose husbands participated in the Korean War, enabling him
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https://en.wikipedia.org/wiki/Seven-dimensional%20cross%20product
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In mathematics, the seven-dimensional cross product is a bilinear operation on vectors in seven-dimensional Euclidean space. It assigns to any two vectors a, b in a vector also in . Like the cross product in three dimensions, the seven-dimensional product is anticommutative and is orthogonal both to a and to b. Unlike in three dimensions, it does not satisfy the Jacobi identity, and while the three-dimensional cross product is unique up to a sign, there are many seven-dimensional cross products. The seven-dimensional cross product has the same relationship to the octonions as the three-dimensional product does to the quaternions.
The seven-dimensional cross product is one way of generalizing the cross product to other than three dimensions, and it is the only other bilinear product of two vectors that is vector-valued, orthogonal, and has the same magnitude as in the 3D case. In other dimensions there are vector-valued products of three or more vectors that satisfy these conditions, and binary products with bivector results.
Multiplication table
The product can be given by a multiplication table, such as the one here. This table, due to Cayley, gives the product of orthonormal basis vectors ei and ej for each i, j from 1 to 7. For example, from the table
The table can be used to calculate the product of any two vectors. For example, to calculate the e1 component of x × y the basis vectors that multiply to produce e1 can be picked out to give
This can be repeated for t
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https://en.wikipedia.org/wiki/Hadamard%20factorization%20theorem
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In mathematics, and particularly in the field of complex analysis, the Hadamard factorization theorem asserts that every entire function with finite order can be represented as a product involving its zeroes and an exponential of a polynomial. It is named for Jacques Hadamard.
The theorem may be viewed as an extension of the fundamental theorem of algebra, which asserts that every polynomial may be factored into linear factors, one for each root. It is closely related to Weierstrass factorization theorem, which does not restrict to entire functions with finite orders.
Formal statement
Define the Hadamard canonical factors Entire functions of finite order have Hadamard's canonical representation:where are those roots of that are not zero (), is the order of the zero of at (the case being taken to mean ), a polynomial (whose degree we shall call ), and is the smallest non-negative integer such that the seriesconverges. The non-negative integer is called the genus of the entire function . In this notation,In other words: If the order is not an integer, then is the integer part of . If the order is a positive integer, then there are two possibilities: or .
Furthermore, Jensen's inequality implies that its roots are distributed sparsely, with critical exponent .
For example, , and are entire functions of genus .
Critical exponent
Define the critical exponent of the roots of as the following:where is the number of roots with modulus . In other words, we hav
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https://en.wikipedia.org/wiki/Bochner%27s%20theorem
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In mathematics, Bochner's theorem (named for Salomon Bochner) characterizes the Fourier transform of a positive finite Borel measure on the real line. More generally in harmonic analysis, Bochner's theorem asserts that under Fourier transform a continuous positive-definite function on a locally compact abelian group corresponds to a finite positive measure on the Pontryagin dual group. The case of sequences was first established by Gustav Herglotz (see also the related Herglotz representation theorem.)
The theorem for locally compact abelian groups
Bochner's theorem for a locally compact abelian group G, with dual group , says the following:
Theorem For any normalized continuous positive-definite function f on G (normalization here means that f is 1 at the unit of G), there exists a unique probability measure μ on such that
i.e. f is the Fourier transform of a unique probability measure μ on . Conversely, the Fourier transform of a probability measure on is necessarily a normalized continuous positive-definite function f on G. This is in fact a one-to-one correspondence.
The Gelfand–Fourier transform is an isomorphism between the group C*-algebra C*(G) and C0(Ĝ). The theorem is essentially the dual statement for states of the two abelian C*-algebras.
The proof of the theorem passes through vector states on strongly continuous unitary representations of G (the proof in fact shows that every normalized continuous positive-definite function must be of this form).
G
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https://en.wikipedia.org/wiki/Normal%20bundle
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In differential geometry, a field of mathematics, a normal bundle is a particular kind of vector bundle, complementary to the tangent bundle, and coming from an embedding (or immersion).
Definition
Riemannian manifold
Let be a Riemannian manifold, and a Riemannian submanifold. Define, for a given , a vector to be normal to whenever for all (so that is orthogonal to ). The set of all such is then called the normal space to at .
Just as the total space of the tangent bundle to a manifold is constructed from all tangent spaces to the manifold, the total space of the normal bundle to is defined as
.
The conormal bundle is defined as the dual bundle to the normal bundle. It can be realised naturally as a sub-bundle of the cotangent bundle.
General definition
More abstractly, given an immersion (for instance an embedding), one can define a normal bundle of N in M, by at each point of N, taking the quotient space of the tangent space on M by the tangent space on N. For a Riemannian manifold one can identify this quotient with the orthogonal complement, but in general one cannot (such a choice is equivalent to a section of the projection ).
Thus the normal bundle is in general a quotient of the tangent bundle of the ambient space restricted to the subspace.
Formally, the normal bundle to N in M is a quotient bundle of the tangent bundle on M: one has the short exact sequence of vector bundles on N:
where is the restriction of the tangent bundle on M to N (prope
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https://en.wikipedia.org/wiki/HAL%20%28robot%29
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The Hybrid Assistive Limb (also known as HAL) is a powered exoskeleton suit developed by Japan's Tsukuba University and the robotics company Cyberdyne. It is designed to support and expand the physical capabilities of its users, particularly people with physical disabilities. There are two primary versions of the system: HAL 3, which only provides leg function, and HAL 5, which is a full-body exoskeleton for the arms, legs, and torso.
In 2011, Cyberdyne and Tsukuba University jointly announced that hospital trials of the full HAL suit would begin in 2012, with tests to continue until 2014 or 2015. By October 2012, HAL suits were in use by 130 different medical institutions across Japan. In February 2013, the HAL system became the first powered exoskeleton to receive global safety certification. In August 2013, HAL received EC certification for clinical use in Europe as the world's first non-surgical medical treatment robot. In addition to its medical applications, the HAL exoskeleton has been used in construction and disaster response work.
History
The first HAL prototype was proposed by Yoshiyuki Sankai, a professor at Tsukuba University. Fascinated with robots since he was in the third grade, Sankai had striven to make a robotic suit in order "to support humans". In 1989, after receiving his PhD in robotics, he began the development of HAL. Sankai spent three years, from 1990 to 1993, mapping out the neurons that govern leg movement. It took him and his team an additional
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https://en.wikipedia.org/wiki/Anne%20Logston
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Anne Logston (born February 15, 1962) is an American author of fantasy/adventure novels.
She was born in Indiana and attended the University of Indianapolis, where she received an associate degree in computer science and a B.A. in English. She worked as a legal secretary.
Works
Shadow series
These are about the "elvan" thief named Shadow, and her niece Jael.
Other novels
Exile is a direct sequel to Guardian's Key, following the life of the original protagonist's daughter.
References
External links
Official website
Bibliography at SciFan
1962 births
Living people
20th-century American novelists
American fantasy writers
American women novelists
Women science fiction and fantasy writers
20th-century American women writers
21st-century American women
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https://en.wikipedia.org/wiki/Surroundings
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Surroundings are the area around a given physical or geographical point or place. The exact definition depends on the field. Surroundings can also be used in geography (when it is more precisely known as vicinity, or vicinage) and mathematics, as well as philosophy, with the literal or metaphorically extended definition.
In thermodynamics, the term (and its synonym, environment) is used in a more restricted sense, meaning everything outside the thermodynamic system. Often, the simplifying assumptions are that energy and matter may move freely within the surroundings, and that the surroundings have a uniform composition.
See also
Distance
Environment (biophysical)
Environment (systems)
Neighbourhood (mathematics)
Social environment
Proxemics
Geography
Thermodynamics
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https://en.wikipedia.org/wiki/Robin%20Popplestone
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Robin John Popplestone (9 December 1938 in Bristol – 14 April 2004 in Glasgow) was a pioneer in the fields of machine intelligence and robotics. He is known for developing the COWSEL and POP programming languages, and for his work on Freddy II with Pat Ambler at the University of Edinburgh Artificial Intelligence laboratory.
Biography
Robin Popplestone was born in Bristol in 1938, but after WWII his family moved to Belfast. He received an honours degree in mathematics from Queen's University Belfast in 1960. He started a PhD at Manchester University before moving to Leeds University. His project was to develop a program for automated theorem proving, but he got caught up in using the university computer to design a boat. He built the boat and set sail for the University of Edinburgh, where he had been offered a research position. A storm hit while crossing the North Sea, and the boat sank. A widely believed story about Popplestone was that he never completed his PhD in mathematics because he lost his thesis manuscript in the boat, although Popplestone refused to corroborate this. The early part of his professional career was spent at the University of Edinburgh (1965-1985) and the later part at the University of Massachusetts Amherst (1985-2001). In 1990, he was elected a Founding Fellow of the Association for the Advancement of Artificial Intelligence. Due to illness, he retired in 2001 to the Glasgow area. He died in 2004 after a 10-year illness with prostate cancer.
Refe
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https://en.wikipedia.org/wiki/C0
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C0 or C00 has several uses including:
C0, the IATA code for Centralwings airline
C0 and C1 control codes
a CPU power state in the Advanced Configuration and Power Interface
an alternate name for crt0, a library used in the startup of a C program
in mathematics:
the differentiability class C0
a C0-semigroup, a strongly continuous one-parameter semigroup
c0, the Banach space of real sequences that converge to zero
a C0 field is an algebraically closed field
in physics, c0, the speed of light in vacuum
%C0, the URL-encoded version of the character "À"
C0, a note-octave in music
an ISO 216 paper format size
C00, the ICD-10 code for oral cancer
could refer to:
An abbreviation for Celsius degrees
In chemistry, the standard state for solute concentration
See also
CO (disambiguation), the two letter combination
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https://en.wikipedia.org/wiki/PBW
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PBW may refer to:
Philadelphia-Baltimore-Washington Stock Exchange
Peanut Butter Wolf, American hip hop record producer
Proton beam writing, a lithography process
Play by Web, Play-by-post role-playing game
Prosopography of the Byzantine World, a prosopographical database project
Poincaré-Birkhoff-Witt theorem, a result in mathematics
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https://en.wikipedia.org/wiki/Takeuti%27s%20conjecture
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In mathematics, Takeuti's conjecture is the conjecture of Gaisi Takeuti that a sequent formalisation of second-order logic has cut-elimination (Takeuti 1953). It was settled positively:
By Tait, using a semantic technique for proving cut-elimination, based on work by Schütte (Tait 1966);
Independently by Prawitz (Prawitz 1968) and Takahashi (Takahashi 1967) by a similar technique (Takahashi 1967) - although Prawitz's and Takahashi's proofs are not limited to second-order logic, but concern higher-order logics in general;
It is a corollary of Jean-Yves Girard's syntactic proof of strong normalization for System F.
Takeuti's conjecture is equivalent to the 1-consistency of second-order arithmetic in the sense that each of the statements can be derived from each other in the weak system PRA. It is also equivalent to the strong normalization of the Girard/Reynold's System F.
See also
Hilbert's second problem
References
Dag Prawitz, 1968. Hauptsatz for higher order logic. J. Symb. Log., 33:452–457, 1968.
William W. Tait, 1966. A nonconstructive proof of Gentzen's Hauptsatz for second order predicate logic. In Bulletin of the American Mathematical Society, 72:980–983.
Gaisi Takeuti, 1953. On a generalized logic calculus. In Japanese Journal of Mathematics, 23:39–96. An errata to this article was published in the same journal, 24:149–156, 1954.
Moto-o Takahashi, 1967. A proof of cut-elimination in simple type theory. In Japanese Mathematical Society, 10:44–45.
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https://en.wikipedia.org/wiki/Bioorthogonal%20chemical%20reporter
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In chemical biology, bioorthogonal chemical reporter is a non-native chemical functionality that is introduced into the naturally occurring biomolecules of a living system, generally through metabolic or protein engineering. These functional groups are subsequently utilized for tagging and visualizing biomolecules. Jennifer Prescher and Carolyn R. Bertozzi, the developers of bioorthogonal chemistry, defined bioorthogonal chemical reporters as "non-native, non-perturbing chemical handles that can be modified in living systems through highly selective reactions with exogenously delivered probes." It has been used to enrich proteins and to conduct proteomic analysis.
In the early development of the technique, chemical motifs have to fulfill criteria of biocompatibility and selective reactivity in order to qualify as bioorthogonal chemical reporters. Some combinations of proteinogenic amino acid side chains meet the criteria, as do ketone and aldehyde tags. Azides and alkynes are other examples of chemical reporters.
A bioorthogonal chemical reporter must be incorporated into a biomolecule. This occurs via metabolism. The chemical reporter is linked to a substrate, which a cell can metabolize.
References
Biochemistry methods
Chemical biology
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https://en.wikipedia.org/wiki/Aphex%20Systems
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Aphex is a brand of audio signal processing equipment. Aphex Systems was founded in 1975 in Massachusetts. The company changed its name to Aphex in 2010.
About Aphex
Formerly Aphex Systems, the company was acquired in mid-2015 by Freedman Electronics, parent company of Røde Microphones.
Aphex moved in 2011 to Burbank, California, and in 2014 moved its main offices to Salt Lake City, Utah. Aphex manufactures pro audio products, primarily in the Burbank and L.A. area, with a few products manufactured in Asia. Aphex has design and engineering facilities located in Salt Lake City and California.
Aphex builds products for the professional audio, broadcast, fixed installation, touring-sound and home-recording markets. It has developed a number of technologies and products, such as the Aural Exciter, Compellor, Dominator, Expander/Gate and Expressor, plus the Model 1100 Two-Channel and Model 1788 Eight-Channel Ultra-Precision Remotely Controllable Microphone Pre-Amplifiers, and the Model 2020 Mk III Broadcast Audio Processor. A key element of all the dynamics processing products is the voltage-controlled attenuator, the Aphex VCA 1001. Another key element is Aphex' input and output circuitry, using electronic balancing techniques instead of transformers. In late 2000, Aphex introduced a digital signal transport product, the Anaconda 64-Channel Bidirectional Digital Snake.
Today, Aphex is focused on its latest Exciter and Big Bottom processing and Compellor compression technologi
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https://en.wikipedia.org/wiki/Polymer%20science
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Polymer science or macromolecular science is a subfield of materials science concerned with polymers, primarily synthetic polymers such as plastics and elastomers. The field of polymer science includes researchers in multiple disciplines including chemistry, physics, and engineering.
Subdisciplines
This science comprises three main sub-disciplines:
Polymer chemistry or macromolecular chemistry is concerned with the chemical synthesis and chemical properties of polymers.
Polymer physics is concerned with the physical properties of polymer materials and engineering applications. Specifically, it seeks to present the mechanical, thermal, electronic and optical properties of polymers with respect to the underlying physics governing a polymer microstructure. Despite originating as an application of statistical physics to chain structures, polymer physics has now evolved into a discipline in its own right.
Polymer characterization is concerned with the analysis of chemical structure, morphology, and the determination of physical properties in relation to compositional and structural parameters.
History of polymer science
The first modern example of polymer science is Henri Braconnot's work in the 1830s. Henri, along with Christian Schönbein and others, developed derivatives of the natural polymer cellulose, producing new, semi-synthetic materials, such as celluloid and cellulose acetate. The term "polymer" was coined in 1833 by Jöns Jakob Berzelius, though Berzelius did li
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https://en.wikipedia.org/wiki/Gabriel%20Carroll
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Gabriel Drew Carroll (born December 24, 1982) is a Professor of Economics at the University of Toronto. He was born to tech industry worker parents in Oakland. He graduated from Harvard University with B.A. in mathematics and linguistics in 2005 and received his doctorate in economics from MIT in 2012. He was recognized as a child prodigy and received numerous awards in mathematics while a student.
Carroll won two gold medals (1998, 2001) and a silver medal (1999) at the International Mathematical Olympiad, earning a perfect score at the 2001 International Mathematical Olympiad held in Washington, D.C., shared only with American teammate Reid W. Barton and Chinese teammates Liang Xiao and Zhiqiang Zhang.
Gabriel earned a place among the top five ranked competitors (who are themselves not ranked against each other) in the William Lowell Putnam Competition all four years that he was eligible (2000–2003), a feat matched by only seven others (Don Coppersmith (1968–1971), Arthur Rubin (1970–1973), Bjorn Poonen (1985–1988), Ravi Vakil (1988–1991), Reid W. Barton (2001–2004), Daniel Kane (2003–2006), and Brian R. Lawrence (2007–08, 2010–11). His top-5 performance in 2000 was particularly notable, as he was officially taking the exam in spite of only being a high school senior, thus forfeiting one of his years of eligibility in college. He was on the first place Putnam team twice (2001–02) and the second place team once (2003).
He has earned awards in science and math, including t
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https://en.wikipedia.org/wiki/Aromatic%20sulfonation
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In organic chemistry, aromatic sulfonation is an organic reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid () functional group in an electrophilic aromatic substitution. Aryl sulfonic acids are used as detergents, dye, and drugs.
Stoichiometry and mechanism
Typical conditions involve heating the aromatic compound with sulfuric acid:
Sulfur trioxide or its protonated derivative is the actual electrophile in this electrophilic aromatic substitution.
To drive the equilibrium, dehydrating agents such as thionyl chloride can be added.
Chlorosulfuric acid is also an effective agent:
In contrast to aromatic nitration and most other electrophilic aromatic substitutions this reaction is reversible. Sulfonation takes place in concentrated acidic conditions and desulfonation is the mode of action in a dilute hot aqueous acid. The reaction is very useful in protecting the aromatic system because of this reversibility. Due to their electron withdrawing effects, sulfonate protecting groups can be used to prevent electrophilic aromatic substitution. They can also be installed as directing groups to affect the position where a substitution may take place.
Specialized sulfonation methods
Many method have been developed for introducing sulfonate groups aside from direction sulfonation.
Piria reaction
A classic named reaction is the Piria reaction (Raffaele Piria, 1851) in which nitrobenzene is reacted with a metal bisulfite forming an aminosulfonic acid as a
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https://en.wikipedia.org/wiki/Walter%20W.%20Marseille
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Walter William Marseille (born 1901) was a German-American psychoanalyst and graphologist. In 1948 he corresponded with Albert Einstein and Bertrand Russell, advocating world government.
Life
Walter Marseille was the son of Gustav Marseille, a leader in the progressive education movement. He studied psychology, mathematics, history, and philosophy at the Universities of Heidelberg, Freiburg, and Munich. In 1926 he took a doctorate under Martin Heidegger at Marburg University. Further information is given by his friend Karl Löwith. From 1928 to 1933 Marseille followed the workshops (Arbeitsgemeinschaft) of Heinrich Jacoby in Berlin; his address was Dernburgstr. 34, Charlottenburg (Berlin). He later claimed to have broken with Heidegger in 1932 over Heidegger's refusal to condemn Nazism. Löwith tells us that Marseille left Germany in 1933, went to Vienna where he married a woman of Jewish origin, and then emigrated to the United States. He trained as a psychoanalyst at the Berlin Psychoanalytic Institute and the Vienna Psychoanalytic Society, and took Ruth Mack Brunswick as his training analyst.
Marseille was hired by Paul Lazarsfeld in 1940 to analyse the handwriting of mail received by US Senators during the debate on the conscription bill, and developed an index for the cultural rating of handwriting.
In April 1948 Marseille sent a paper, "A Method to Enforce World Peace", to both Bertrand Russell and Albert Einstein. A copy of the paper is in the Einstein archives along
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https://en.wikipedia.org/wiki/Abundance
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Abundance may refer to:
In science and technology
Abundance (economics), the opposite of scarcities
Abundance (ecology), the relative representation of a species in a community
Abundance (programming language), a Forth-like computer programming language
Abundance and abundancy index are related but distinct notions in mathematics, see abundant number
In chemistry:
Abundance (chemistry), when a substance in a reaction is present in high quantities
Abundance of the chemical elements, a measure of how common elements are
Natural abundance, the natural prevalence of different isotopes of an element on Earth
Abundance of elements in Earth's crust
In literature
Abundance (novel), a 2021 novel by Jakob Guanzon
Abundance (play), a 1990 stage play written by Beth Henley
Al-Kawthar ("Abundance"), the 108th sura of the Qur'an
Abundance: The Future Is Better Than You Think, a 2012 book by Peter Diamandis and Steven Kotler
Other uses
Abundance Generation, a renewable energy investment platform
Fountain de la Abundancia, a former fountain in Madrid
Abundance, Royal Abundance and Abundance Declared, bids in the card game Solo whist; sometimes spelled "abondance"
See also
Abondance (disambiguation)
Abundant life (disambiguation)
Abundantia, a Roman goddess
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https://en.wikipedia.org/wiki/List%20of%20things%20named%20after%20Leonhard%20Euler
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In mathematics and physics, many topics are named in honor of Swiss mathematician Leonhard Euler (1707–1783), who made many important discoveries and innovations. Many of these items named after Euler include their own unique function, equation, formula, identity, number (single or sequence), or other mathematical entity. Many of these entities have been given simple and ambiguous names such as Euler's function, Euler's equation, and Euler's formula.
Euler's work touched upon so many fields that he is often the earliest written reference on a given matter. In an effort to avoid naming everything after Euler, some discoveries and theorems are attributed to the first person to have proved them after Euler.
Conjectures
Euler's conjecture (Waring's problem)
Euler's sum of powers conjecture
Euler's Graeco-Latin square conjecture
Equations
Usually, Euler's equation refers to one of (or a set of) differential equations (DEs). It is customary to classify them into ODEs and PDEs.
Otherwise, Euler's equation may refer to a non-differential equation, as in these three cases:
Euler–Lotka equation, a characteristic equation employed in mathematical demography
Euler's pump and turbine equation
Euler transform used to accelerate the convergence of an alternating series and is also frequently applied to the hypergeometric series
Ordinary differential equations
Euler rotation equations, a set of first-order ODEs concerning the rotations of a rigid body.
Euler–Cauchy equation, a linear e
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https://en.wikipedia.org/wiki/Tangle
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Tangle may refer to:
Science, Technology, Engineering & Mathematics
The Tangle is the name of the ledger, a directed acyclic graph, used for the cryptocurrency IOTA
Tangle (mathematics), a topological object
Natural sciences & medicine
Sea tangle, another name for kelp
Neurofibrillary tangles, which occur in Alzheimer's disease
Music
Tangle (album), a 1989 album by Thinking Fellers Union Local 282
Tangle (EP), a 2016 extended play by Trash Talk
Tangles (album), a 2005 album by S. J. Tucker
Social media
tangle.com, a Christian social networking site
Fiction
Tangle (TV series), an Australian television series
Tangle, a character in The Golden Key by George MacDonald
The Tangle is a 2019 sci-fi film by Christopher Soren Kelly.
Tangle the Lemur, a character from IDW Publishing comic series Sonic the Hedgehog
"Tangles", a Hugo Award-nominated story by Seanan McGuire
See also
Tangled (disambiguation)
Knot
Rectangle
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https://en.wikipedia.org/wiki/Lead%20dioxide
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Lead(IV) oxide, commonly known as lead dioxide, is an inorganic compound with the chemical formula . It is an oxide where lead is in an oxidation state of +4. It is a dark-brown solid which is insoluble in water. It exists in two crystalline forms. It has several important applications in electrochemistry, in particular as the positive plate of lead acid batteries.
Properties
Physical
Lead dioxide has two major polymorphs, alpha and beta, which occur naturally as rare minerals scrutinyite and plattnerite, respectively. Whereas the beta form had been identified in 1845, α- was first identified in 1946 and found as a naturally occurring mineral 1988.
The alpha form has orthorhombic symmetry, space group Pbcn (No. 60), Pearson symbol oP12, lattice constants a = 0.497 nm, b = 0.596 nm, c = 0.544 nm, Z = 4 (four formula units per unit cell). The lead atoms are six-coordinate.
The symmetry of the beta form is tetragonal, space group P42/mnm (No. 136), Pearson symbol tP6, lattice constants a = 0.491 nm, c = 0.3385 nm, Z = 2 and related to the rutile structure and can be envisaged as containing columns of octahedra sharing opposite edges and joined to other chains by corners. This contrasts with the alpha form where the octahedra are linked by adjacent edges to give zigzag chains.
Chemical
Lead dioxide decomposes upon heating in air as follows:
The stoichiometry of the end product can be controlled by changing the temperature – for example, in the above reaction, the first st
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https://en.wikipedia.org/wiki/Dihedral%20group%20of%20order%206
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In mathematics, D3 (sometimes alternatively denoted by D6) is the dihedral group of degree 3 and order 6. It equals the symmetric group S3. It is also the smallest non-abelian group.
This page illustrates many group concepts using this group as example.
Symmetry groups
The dihedral group D3 is the symmetry group of an equilateral triangle, that is, it is the set of all transformations such as reflection, rotation, and combinations of these, that leave the shape and position of this triangle fixed. In the case of D3, every possible permutation of the triangle's vertices constitutes such a transformation, so that the group of these symmetries is isomorphic to the symmetric group S3 of all permutations of three distinct elements. This is not the case for dihedral groups of higher orders.
The dihedral group D3 is isomorphic to two other symmetry groups in three dimensions:
one with a 3-fold rotation axis and a perpendicular 2-fold rotation axis (hence three of these): D3
one with a 3-fold rotation axis in a plane of reflection (and hence also in two other planes of reflection): C3v
Permutations of a set of three objects
Consider three colored blocks (red, green, and blue), initially placed in the order RGB. The symmetric group S3 is then the group of all possible rearrangements of these blocks.
If we denote by a the action "swap the first two blocks", and by b the action "swap the last two blocks", we can write all possible permutations in terms of these two actions.
In mult
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https://en.wikipedia.org/wiki/Basic%20fighter%20maneuvers
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Basic fighter maneuvers (BFM) are tactical movements performed by fighter aircraft during air combat maneuvering (ACM, also called dogfighting), to gain a positional advantage over the opponent. BFM combines the fundamentals of aerodynamic flight and the geometry of pursuit, with the physics of managing the aircraft's energy-to-mass ratio, called its specific energy.
Maneuvers are used to gain a better angular position in relation to the opponent. They can be offensive, to help an attacker gain an advantage on an enemy; or defensive, to help the defender evade an attacker's weapons. They can also be neutral, where both opponents strive for an offensive position or disengagement maneuvers, to help an escape.
Classic maneuvers include the lag pursuit or yo-yo, which add distance when the attacker may overshoot the target due to higher airspeed, the low yo-yo, which does the opposite when the attacker is flying too slow, the scissors, which attempts to drive the attacker in front of the defender, and the defensive spiral, which allows a defender to disengage from an attacker.
Situational awareness is often taught as the best tactical defense, removing the possibility of an attacker getting or remaining behind the pilot; even with speed, a fighter is open to attack from the rear.
Introduction
Basic fighter maneuvers (BFM) are actions that a fighter aircraft makes during air combat maneuvering, historically known as dogfighting. The development of BFM began with the first figh
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https://en.wikipedia.org/wiki/Rupert%20Riedl
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Rupert Riedl (22 February 1925 – 18 September 2005) was an Austrian zoologist.
Biography
Riedl was a scientist with broad interests, whose influence in epistemology grounded in evolutionary theory was notable, although less in English-speaking circles than in German or even Spanish speaking ones. His 1984 work, Biology of Knowledge: The evolutionary basis of reason examined cognitive abilities and the increasing complexity of biological diversification over the immense periods of evolutionary time.
Riedl built upon the work of the Viennese school of thought initially typified by Konrad Lorenz, and continued in Vienna by Gerhard Vollmer, Franz Wuketits, and in Spain by Nicanor Ursura. Riedl was skeptical of German idealism, and nourished by the tradition that produced the scientists and philosophers of science Ernst Mach, Ludwig Boltzmann, Erwin Schrödinger, Karl Popper, Hans Reichenbach and Sigmund Freud.
Lorenz believed that the Kantian framework of cognitive concepts such as three-dimensional space and time were not fixed but built up over phylogenetic history, potentially subject to further developments. Lorenz’s position, as expanded by Riedl, attempted to make it easier to assimilate non-common sense areas of physics such as quantum field theory and string theory.
Riedl drew clear distinctions between the deductive and inductive (non conscious) cognitive processes characteristic of the left and right cerebral hemispheres. His analysis of what he called "the pitfalls
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https://en.wikipedia.org/wiki/John%20Henry%20Michell
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John Henry Michell, FRS (26 October 1863 – 3 February 1940) was an Australian mathematician and Professor of Mathematics at the University of Melbourne.
Early life
Michell was the son of John Michell (pronounced Mitchell), a miner, and his wife Grace, née Rowse, and was born in Maldon, Victoria. His parents had migrated from Devonshire in 1854. Educated first at Maldon, he went to Wesley College, Melbourne, in 1877, where he won the Draper and Walter Powell scholarships. In 1881 he began the arts course at the University of Melbourne, and qualified for the B.A. degree at the end of 1883. He had an outstanding course, heading the list with first-class honours each year, and winning the final honour scholarship in mathematics and physics.
Michell then went to the University of Cambridge, obtained a major scholarship at Trinity College, and was bracketed senior wrangler with three others in the first part of the mathematical tripos in 1887. In the second part of the tripos in 1888, Michell was placed in division one of the first class.
University of Melbourne
Michell was elected a fellow of Trinity in 1890, but returned to Melbourne later the same year, and was appointed lecturer in mathematics at Melbourne University. He held this position for over 30 years. His academic work occupied so much of his time that it was difficult to do original research. The first of his papers, "On the theory of free streamlines", which appeared in Transactions of the Royal Society in 1890, ha
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https://en.wikipedia.org/wiki/Vikrant%20Bhargava
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Vikrant Bhargava (विक्रान्त भार्गव; born 14 December 1972) is an Indian-born British businessman, and the co-founder and former marketing director of online casino operator PartyGaming.
Early life
Bhargava is an alumnus of the Indian Institute of Management Calcutta, and also holds a bachelor's degree in Technology in electrical engineering from IIT Delhi.
Career
Prior to joining PartyGaming, Bhargava was a credit officer at Bank of America, responsible for managing credit exposure and revenue for corporate clients, and a business analyst in the business development division of British Gas.
Bhargava joined PartyGaming (formerly iGlobalMedia) as marketing director in early 2000. In July 2001, he oversaw the marketing for the launch of PartyPoker, and was the face of Partygaming when it went public in 2005, at the time the London Stock Exchange's largest IPO of an internet company, valued at over $8 Billion.
In May 2006, Bhargava announced he would leave the company's board of directors at the end of the year. He also stepped down from his executive role in the company. Quoted in eGaming Review, John Shepherd, director of PartyGaming corporate communications, credited Bhargava with transforming PartyGaming into a multi-billion pound company. At the time of leaving PartyGaming, Bhargava's fortune was estimated to be £850 million. ($1.6 billion at that time)
Bhargava later became the head of a private investment company, Veddis Ventures, registered in Gibraltar. According to
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https://en.wikipedia.org/wiki/Matmatah
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Matmatah is a French rock band, established in 1995 in Brest, Brittany.
History
The band was established in 1995 when Tristan Nihouarn, who at the time was a student pursuing study of Advanced Mathematics in Brest (western Brittany, France), met Cédric Floc'h who was studying electric engineering in the same city, where they both come from. Both were guitarists and together formed a chanson and guitar duo called the Tricards Twins, playing in a number of bars and pubs in Brittany. They developed a repertoire for playing songs from the sixties and seventies, with the Beatles, Neil Young and Simon and Garfunkel figuring prominently among their influences.
In one of their shows, they met bassist Eric Digaire and drummer Jean-François Paillard. Together, they formed Matmatah, named after Matmata, the village in Tunisia in which Nihouarn had lived during his childhood. Their first single, including two songs, "Lambé An Dro" and "Les Moutons" (The Sheep), was released in 1997, and within a few months had sold 30,000 copies.
The following studio album, La Ouache, sold 300,000 copies within six months (800,000 in total).
In 2001, the band released their live album, Lust for a Live, and a DVD entitled Piste Off. After a short rest period during which the band changed drummer they resumed their touring, this time for a number of humanitarian causes.
Their third studio album, Archie Kramer, released in October 2004, featured the singles Casi El Silencio and Au Conditionnel.
At t
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https://en.wikipedia.org/wiki/Mathematics%20education%20in%20New%20York
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Mathematics education in New York in regard to both content and teaching method can vary depending on the type of school a person attends. Private school math education varies between schools whereas New York has statewide public school requirements where standardized tests are used to determine if the teaching method and educator are effective in transmitting content to the students. While an individual private school can choose the content and educational method to use, New York State mandates content and methods statewide. Some public schools have and continue to use established methods, such as Montessori for teaching such required content. New York State has used various foci of content and methods of teaching math including New Math (1960s), 'back to the basics' (1970s), Whole Math (1990s), Integrated Math, and Everyday Mathematics.
How to teach math, what to teach, and its effectiveness has been a topic of debate in New York State and nationally since the "Math Wars" started in the 1960s. Often, current political events influence how and what is taught. The politics in turn influence state legislation. California, New York, and several other states have influenced textbook content produced by publishers.
The state of New York has implemented a novel curriculum for high school mathematics.
The courses Algebra I, Geometry, and Algebra II/Trigonometry are required courses mandated by the New York State Department of Education for high school graduation.
2007-present
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https://en.wikipedia.org/wiki/Paul%20Kay
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Paul Kay (born 1934 in New York) is an emeritus professor of linguistics at the University of California, Berkeley, United States. He joined the University in 1966 as a member of the Department of Anthropology, transferring to the Department of Linguistics in 1982 and now working at the International Computer Science Institute (ICSI). He is best known for his work with anthropologist Brent Berlin on colour: Basic Color Terms: Their Universality and Evolution (1969) . More recently, he has worked in the area of Construction Grammar with Charles J. Fillmore, authoring the textbook Construction Grammar (1996 manuscript). He is currently working on an extension of Construction Grammar called Sign-Based Construction Grammar, authoring a book on this topic with Charles J. Fillmore, Ivan Sag and Laura Michaelis.
Since 2005 Kay has returned to experimental testing of the Sapir-Whorf hypothesis and his findings show that taking into account brain lateralization allows another perspective on the debate. More specifically he proposed that "Whorf hypothesis is supported in the right visual field but not the left".
See also
Lazarus Geiger
References
External links
Personal website
UC Berkeley faculty page
1934 births
Members of the United States National Academy of Sciences
Living people
Linguists from the United States
University of California, Berkeley College of Letters and Science faculty
Fellows of the Cognitive Science Society
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https://en.wikipedia.org/wiki/List%20of%20mesons
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This list is of all known and predicted scalar, pseudoscalar and vector mesons. See list of particles for a more detailed list of particles found in particle physics.
This article contains a list of mesons, unstable subatomic particles composed of one quark and one antiquark. They are part of the hadron particle family—particles made of quarks. The other members of the hadron family are the baryons—subatomic particles composed of three quarks. The main difference between mesons and baryons is that mesons have integer spin (thus are bosons) while baryons are fermions (half-integer spin). Because mesons are bosons, the Pauli exclusion principle does not apply to them. Because of this, they can act as force mediating particles on short distances, and thus play a part in processes such as the nuclear interaction.
Since mesons are composed of quarks, they participate in both the weak and strong interactions. Mesons with net electric charge also participate in the electromagnetic interaction. They are classified according to their quark content, total angular momentum, parity, and various other properties such as C-parity and G-parity. While no meson is stable, those of lower mass are nonetheless more stable than the most massive mesons, and are easier to observe and study in particle accelerators or in cosmic ray experiments. They are also typically less massive than baryons, meaning that they are more easily produced in experiments, and will exhibit higher-energy phenomena soon
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https://en.wikipedia.org/wiki/Liquid%20chromatography%E2%80%93mass%20spectrometry
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Liquid chromatography–mass spectrometry (LC–MS) is an analytical chemistry technique that combines the physical separation capabilities of liquid chromatography (or HPLC) with the mass analysis capabilities of mass spectrometry (MS). Coupled chromatography - MS systems are popular in chemical analysis because the individual capabilities of each technique are enhanced synergistically. While liquid chromatography separates mixtures with multiple components, mass spectrometry provides spectral information that may help to identify (or confirm the suspected identity of) each separated component. MS is not only sensitive, but provides selective detection, relieving the need for complete chromatographic separation. LC–MS is also appropriate for metabolomics because of its good coverage of a wide range of chemicals. This tandem technique can be used to analyze biochemical, organic, and inorganic compounds commonly found in complex samples of environmental and biological origin. Therefore, LC–MS may be applied in a wide range of sectors including biotechnology, environment monitoring, food processing, and pharmaceutical, agrochemical, and cosmetic industries. Since the early 2000s, LC–MS (or more specifically LC–MS–MS) has also begun to be used in clinical applications.
In addition to the liquid chromatography and mass spectrometry devices, an LC–MS system contains an interface that efficiently transfers the separated components from the LC column into the MS ion source. The interfa
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https://en.wikipedia.org/wiki/Pierre%20Berthelot
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Pierre Berthelot (; born 1943) is a mathematician at the University of Rennes. He developed crystalline cohomology and rigid cohomology.
Publications
Berthelot, Pierre Cohomologie cristalline des schémas de caractéristique p>0. Lecture Notes in Mathematics, Vol. 407. Springer-Verlag, Berlin-New York, 1974. 604 pp.
Berthelot, Pierre; Ogus, Arthur Notes on crystalline cohomology. Princeton University Press, Princeton, N.J.; University of Tokyo Press, Tokyo, 1978. vi+243 pp.
References
Home page of Pierre Berthelot
External links
Author profile in the database zbMATH
Living people
École Normale Supérieure alumni
Algebraic geometers
20th-century French mathematicians
University of Paris alumni
Academic staff of the University of Rennes
1943 births
21st-century French mathematicians
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https://en.wikipedia.org/wiki/HIV%20disease%20progression%20rates
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Following infection with HIV-1, the rate of clinical disease progression varies between individuals. Factors such as host susceptibility, genetics and immune function, health care and co-infections as well as viral genetic variability may affect the rate of progression to the point of needing to take medication in order not to develop AIDS.
Rapid progressors
A small percentage of HIV-infected individuals rapidly progress to AIDS if they fail to take the medication within four years after primary HIV-infection and are termed Rapid Progressors (RP). Indeed, some individuals have been known to progress to AIDS and death within a year after primo-infection. Rapid progression was originally thought to be continent specific, as some studies reported that disease progression is more rapid in Africa, but others have contested this view.
Long term non-progressors
Another subset of individuals who are persistently infected with HIV-1, but show no signs of disease progression for over 12 years and remain asymptomatic are classified as Long Term Non-Progressors (LTNP). In these individuals, it seems that HIV-infection has been halted with regard to disease progression over an extended period of time. However, the term LTNP is a misnomer as that progression towards AIDS can occur even after 15 years of stable infection. LTNP are not a homogeneous group regarding both viral load and specific immune responses against HIV-1. Some LTNPs are infected with HIV that inefficiently replicates w
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https://en.wikipedia.org/wiki/Glayde%20Whitney
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Glayde D. Whitney (1939 – 8 January 2002) was an American behavioral geneticist and psychologist. He was professor at Florida State University. Beyond his work into the genetics of sensory system function in mice, in his later life he supported David Duke as well as research into race and intelligence and eugenics.
Biography
Whitney was born in Montana and grew up in Minnesota. He earned his bachelor's degree from the University of Minnesota, as well as his doctorate from there in 1966. He then enlisted in the United States Air Force and served until 1969. He subsequently worked as a postdoctoral fellow at the Institute for Behavioral Genetics (University of Colorado at Boulder), under Gerald McClearn and John C. DeFries.
In 1970, Whitney was hired by Florida State University to represent behavioral genetics in the psychobiology program, where he stayed until his death at the age of 62 on January 8, 2002, after contracting a severe cold that aggravated emphysema. He considered himself to be a "Hubert Humphrey liberal."
Academic work
Whitney was the author of over 60 papers on the genetics of taste sensitivity in inbred mice. Support for some of this work came from a Claude Pepper Award for Research Excellence from the National Institute on Deafness and Other Communication Disorders and in 1994 he received the Manheimer Lectureship Award from the Monell Chemical Senses Center, which recognizes career achievements of individuals in the chemosensory sciences. He was the pres
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https://en.wikipedia.org/wiki/Devolution%20%28biology%29
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Devolution, de-evolution, or backward evolution (not to be confused with dysgenics) is the notion that species can revert to supposedly more primitive forms over time. The concept relates to the idea that evolution has a purpose (teleology) and is progressive (orthogenesis), for example that feet might be better than hooves or lungs than gills. However, evolutionary biology makes no such assumptions, and natural selection shapes adaptations with no foreknowledge of any kind. It is possible for small changes (such as in the frequency of a single gene) to be reversed by chance or selection, but this is no different from the normal course of evolution and as such de-evolution is not compatible with a proper understanding of evolution due to natural selection.
In the 19th century, when belief in orthogenesis was widespread, zoologists (such as Ray Lankester and Anton Dohrn) and the palaeontologists Alpheus Hyatt and Carl H. Eigenmann advocated the idea of devolution. The concept appears in Kurt Vonnegut's 1985 novel Galápagos, which portrays a society that has evolved backwards to have small brains.
Dollo's law of irreversibility, first stated in 1893 by the palaeontologist Louis Dollo, denies the possibility of devolution. The evolutionary biologist Richard Dawkins explains Dollo's law as being simply a statement about the improbability of evolution's following precisely the same path twice.
Context
The idea of devolution is based on the presumption of orthogenesis, the view
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https://en.wikipedia.org/wiki/Rational%20normal%20curve
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In mathematics, the rational normal curve is a smooth, rational curve of degree in projective n-space . It is a simple example of a projective variety; formally, it is the Veronese variety when the domain is the projective line. For it is the plane conic and for it is the twisted cubic. The term "normal" refers to projective normality, not normal schemes. The intersection of the rational normal curve with an affine space is called the moment curve.
Definition
The rational normal curve may be given parametrically as the image of the map
which assigns to the homogeneous coordinates the value
In the affine coordinates of the chart the map is simply
That is, the rational normal curve is the closure by a single point at infinity of the affine curve
Equivalently, rational normal curve may be understood to be a projective variety, defined as the common zero locus of the homogeneous polynomials
where are the homogeneous coordinates on . The full set of these polynomials is not needed; it is sufficient to pick of these to specify the curve.
Alternate parameterization
Let be distinct points in . Then the polynomial
is a homogeneous polynomial of degree with distinct roots. The polynomials
are then a basis for the space of homogeneous polynomials of degree . The map
or, equivalently, dividing by
is a rational normal curve. That this is a rational normal curve may be understood by noting that the monomials
are just one possible basis for the space of degree homo
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https://en.wikipedia.org/wiki/Rational%20surface
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In algebraic geometry, a branch of mathematics, a rational surface is a surface birationally equivalent to the projective plane, or in other words a rational variety of dimension two. Rational surfaces are the simplest of the 10 or so classes of surface in the Enriques–Kodaira classification of complex surfaces,
and were the first surfaces to be investigated.
Structure
Every non-singular rational surface can be obtained by repeatedly blowing up a minimal rational surface. The minimal rational surfaces are the projective plane and the Hirzebruch surfaces Σr for r = 0 or r ≥ 2.
Invariants: The plurigenera are all 0 and the fundamental group is trivial.
Hodge diamond:
where n is 0 for the projective plane, and 1 for Hirzebruch surfaces
and greater than 1 for other rational surfaces.
The Picard group is the odd unimodular lattice I1,n, except for the Hirzebruch surfaces Σ2m when it is the even unimodular lattice II1,1.
Castelnuovo's theorem
Guido Castelnuovo proved that any complex surface such that q and P2 (the irregularity and second plurigenus) both vanish is rational. This is used in the Enriques–Kodaira classification to identify the rational surfaces. proved that Castelnuovo's theorem also holds over fields of positive characteristic.
Castelnuovo's theorem also implies that any unirational complex surface is rational, because if a complex surface is unirational then its irregularity and plurigenera are bounded by those of a rational surface and are therefore all
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https://en.wikipedia.org/wiki/Sexual%20jealousy
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Sexual jealousy is a special form of jealousy in sexual relationships, based on suspected or imminent sexual infidelity. The concept is studied in the field of evolutionary psychology.
Basis
Evolutionary psychologists have suggested that there is a gender difference in sexual jealousy, driven by men and women's different reproductive biology. The theory proposes that a man perceives a threat to his relationship's future because he could be fooled into raising children that are not his own. In contrast, a woman risks losing to another the relationship and all the benefits that entails. Research has shown that men are impacted more by sexual infidelity, while women are more impacted by emotional infidelity.
An alternative explanation is from a social-cognitive perspective. Typically, men place importance on their masculinity and sexual dominance. When the male's partner commits sexual infidelity, these two components of his ego become severely threatened. Women are more emotionally invested in a relationship, and therefore experience a threat to their self-perception when a partner commits infidelity, more concerned with risk to the emotional content than the sexual.
Some research has suggested that there are no gender differences in sexual jealousy, concluding that males and females both equally experience distress over emotional and sexual infidelity. Sexual jealousy is cross-culturally universal but how it manifests itself may differ across cultures.
Gender-specific beh
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https://en.wikipedia.org/wiki/Matrix%20congruence
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In mathematics, two square matrices A and B over a field are called congruent if there exists an invertible matrix P over the same field such that
PTAP = B
where "T" denotes the matrix transpose. Matrix congruence is an equivalence relation.
Matrix congruence arises when considering the effect of change of basis on the Gram matrix attached to a bilinear form or quadratic form on a finite-dimensional vector space: two matrices are congruent if and only if they represent the same bilinear form with respect to different bases.
Note that Halmos defines congruence in terms of conjugate transpose (with respect to a complex inner product space) rather than transpose, but this definition has not been adopted by most other authors.
Congruence over the reals
Sylvester's law of inertia states that two congruent symmetric matrices with real entries have the same numbers of positive, negative, and zero eigenvalues. That is, the number of eigenvalues of each sign is an invariant of the associated quadratic form.
See also
Congruence relation
Matrix similarity
Matrix equivalence
References
Linear algebra
Matrices
Equivalence (mathematics)
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https://en.wikipedia.org/wiki/Gabriel%20Mouton
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Gabriel Mouton (1618 – 28 September 1694) was a French abbot and scientist. He was a doctor of theology from Lyon, but was also interested in mathematics and astronomy. His 1670 book, the Observationes diametrorum solis et lunae apparentium, proposed a natural standard of length based on the circumference of the Earth, divided decimally. It was influential in the adoption of the metric system in 1799.
The milliare
Based on the measurements of the size of the Earth conducted by Riccioli of Bologna (at 321,815 Bologna feet to the degree), Mouton proposed a decimal system of measurement based on the circumference of the Earth, explaining the advantages of a system based on nature.
His suggestion was a unit, the milliare, that was defined as a minute of arc along a meridian arc, and a system of sub-units, dividing successively by factors of ten into the centuria, decuria, virga, virgula, decima, centesima, and millesima. The virga, 1/1000 of a minute of arc, corresponding to 64.4 Bologna inches, or ~2.04 m, was reasonably close to the then current unit of length, the Parisian toise (~1.95 m) – a feature which was meant to make acceptance of the new unit easier.
As a practical implementation, Mouton suggested that the actual standard be based on pendulum movement, so that a pendulum located in Lyon of length one virgula (1/10 virga) would change direction 3959.2 times in half an hour. The resulting pendulum would have a length of ~20.54 cm.
His ideas attracted interest at t
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https://en.wikipedia.org/wiki/Bioconductor
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Bioconductor is a free, open source and open development software project for the analysis and comprehension of genomic data generated by wet lab experiments in molecular biology.
Bioconductor is based primarily on the statistical R programming language, but does contain contributions in other programming languages. It has two releases each year that follow the semiannual releases of R. At any one time there is a release version, which corresponds to the released version of R, and a development version, which corresponds to the development version of R. Most users will find the release version appropriate for their needs. In addition there are many genome annotation packages available that are mainly, but not solely, oriented towards different types of microarrays.
While computational methods continue to be developed to interpret biological data, the Bioconductor project is an open source software repository that hosts a wide range of statistical tools developed in the R programming environment. Utilizing a rich array of statistical and graphical features in R, many Bioconductor packages have been developed to meet various data analysis needs. The use of these packages provides a basic understanding of the R programming / command language. As a result, R and Bioconductor packages, which have a strong computing background, are used by most biologists who will benefit significantly from their ability to analyze datasets. All these results provide biologists with easy access t
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https://en.wikipedia.org/wiki/Input%20queue
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In computer science, an input queue is a collection of processes in storage that are waiting to be brought into memory to run a program. Input queues are mainly used in Operating System Scheduling which is a technique for distributing resources among processes. Input queues not only apply to operating systems (OS), but may also be applied to scheduling inside networking devices. The purpose of scheduling is to ensure resources are being distributed fairly and effectively; therefore, it improves the performance of the system.
Essentially, a queue is a collection which has data added in the rear position and removed from the front position. There are many different types of queues, and the ways they operate may be totally different.
Operating systems use First-Come, First-Served queues, Shortest remaining time, Fixed priority pre-emptive scheduling, round-robin scheduling and multilevel queue scheduling.
Network devices use First-In-First-Out queue, Weighted fair queue, Priority queue and Custom queue.
Operating system
In operating systems, processes are loaded into memory, and wait for their turn to be executed by the central processing unit (CPU). CPU scheduling manages process states and decides when a process will be executed next by using the input queue.
First-Come, First-out
First-Come, First-out processes are taken out from the queue in consecutive order that they are put into the queue. With this method, every process is treated equally. If there are two proces
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https://en.wikipedia.org/wiki/Potentiality%20and%20actuality
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In philosophy, potentiality and actuality are a pair of closely connected principles which Aristotle used to analyze motion, causality, ethics, and physiology in his Physics, Metaphysics, Nicomachean Ethics, and De Anima.
The concept of potentiality, in this context, generally refers to any "possibility" that a thing can be said to have. Aristotle did not consider all possibilities the same, and emphasized the importance of those that become real of their own accord when conditions are right and nothing stops them.
Actuality, in contrast to potentiality, is the motion, change or activity that represents an exercise or fulfillment of a possibility, when a possibility becomes real in the fullest sense.
These concepts, in modified forms, remained very important into the Middle Ages, influencing the development of medieval theology in several ways. In modern times the dichotomy has gradually lost importance, as understandings of nature and deity have changed. However the terminology has also been adapted to new uses, as is most obvious in words like energy and dynamic. These were words first used in modern physics by the German scientist and philosopher, Gottfried Wilhelm Leibniz. Aristotle's concept of entelechy retains influence on recent concepts of biological "entelechy".
Potentiality
"Potentiality" and "potency" are translations of the Ancient Greek word (δύναμις). They refer especially to the way the word is used by Aristotle, as a concept contrasting with "actuality
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https://en.wikipedia.org/wiki/Engineering%20cybernetics
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Engineering cybernetics also known as technical cybernetics or cybernetic engineering, is the branch of cybernetics concerned with applications in engineering, in fields such as control engineering and robotics.
History
Qian Xuesen (Hsue-Shen Tsien) defined engineering cybernetics as a theoretical field of "engineering science", the purpose of which is to "study those parts of the broad science of cybernetics which have direct engineering applications in designing controlled or guided systems". Published in 1954, Qian's published work "Engineering Cybernetics" describes the mathematical and engineering concepts of cybernetic ideas as understood at the time, breaking them down into granular scientific concepts for application. Qian's work is notable for going beyond model-based theories and arguing for the necessity of a new design principle for types of system the properties
and characteristics of which are largely unknown.
In the 2020s, concerns with the social consequences of cyber-physical systems, have led to calls to develop "a new branch of engineering", "drawing on the history of cybernetics and reimagining it for our 21st century challenges".
Popular usage
1960's - An example of engineering cybernetics is a device designed in the mid-1960s by General Electric Company. Referred to as a CAM (cybernetic anthropomorphous machine), this machine was designed for use by the US Army ground troops. Operated by one man in a "cockpit" at the front end, the machine's "legs" s
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https://en.wikipedia.org/wiki/Bernhard%20Preim
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Bernhard Preim (born 1969) is a specialist in human–computer interface design as well as in visual computing for medicine.
He is currently professor of visualization at University of Magdeburg, Germany.
Preim received the diploma in computer science in 1994 (minor in mathematics) and a PhD in 1998 from the Otto-von-Guericke University Magdeburg (PhD thesis "Interactive Illustrations and Animations for the Exploration of Spatial Relations", supervised by Thomas Strothotte). In 1999, he joined the staff of MeVis (Center for Medical Diagnosis System and Visualization, headed by Heinz-Otto Peitgen). In close collaboration with radiologists and surgeons, he directed the work on "computer-aided planning in liver surgery" and initiated several projects funded by the German Research Council in the area of computer-aided surgery. In June 2002, he received the Habilitation degree (venia legendi) for computer science from the University of Bremen. Since Mars 2003 he is full professor for "Visualization" at the computer science department at the Otto-von-Guericke-University of Magdeburg, heading a research group which is focussed on medical visualization and applications in surgical education and surgery planning. These developments are summarized in a comprehensive textbook Visualization in Medicine (Co-author Dirk Bartz), which appeared at Morgan Kaufmann in June 2007.
Bernhard Preim was founding speaker of the working group Medical Visualization in the German Society for Computer Sc
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https://en.wikipedia.org/wiki/The%20Lives%20of%20a%20Cell%3A%20Notes%20of%20a%20Biology%20Watcher
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The Lives of a Cell: Notes of a Biology Watcher (1974) is collection of 29 essays written by Lewis Thomas for The New England Journal of Medicine between 1971 and 1973. Throughout his essays, Thomas touches on subjects as various as biology, anthropology, medicine, music (showing a particular affinity for Bach), etymology, mass communication, and computers. The pieces resonate with the underlying theme of the interconnected nature of Earth and all living things.
Background
Lewis Thomas was a physician, immunology researcher, dean, poet, etymologist, and essayist. He attended Princeton University followed by Harvard Medical School. He was a research fellow at the Thorndyke Memorial laboratories, and a researcher at Tulane University and University of Minnesota. He was the head of the pathology department at New York University Medical School for fifteen years as well as the chair for the Department of Medicine at Bellevue Hospital. He became the dean of the New York University Medical School and later of Yale School of Medicine. Thomas began writing a monthly essay “Notes of a Biology Watcher” in the New England Journal of Medicine in 1971 while he was at Yale. In 1973 he became the president of the Sloan-Kettering Institute in New York.
Lewis Thomas published multiple books throughout his career, the first being The Lives of a Cell: Notes of a Biology Watcher. In 1979 he published The Medusa and the Snail: More Notes of a Biology Watcher. He wrote an autobiographical book i
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https://en.wikipedia.org/wiki/Bootstrapping%20%28compilers%29
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In computer science, bootstrapping is the technique for producing a self-compiling compiler – that is, a compiler (or assembler) written in the source programming language that it intends to compile. An initial core version of the compiler (the bootstrap compiler) is generated in a different language (which could be assembly language); successive expanded versions of the compiler are developed using this minimal subset of the language. The problem of compiling a self-compiling compiler has been called the chicken-or-egg problem in compiler design, and bootstrapping is a solution to this problem.
Bootstrapping is a fairly common practice when creating a programming language. Many compilers for many programming languages are bootstrapped, including compilers for BASIC, ALGOL, C, C#, D, Pascal, PL/I, Haskell, Modula-2, Oberon, OCaml, Common Lisp, Scheme, Go, Java, Elixir, Rust, Python, Scala, Nim, Eiffel, TypeScript, Vala, Zig and more.
Process
A typical bootstrap process works in three or four stages:
Stage 0: preparing an environment for the bootstrap compiler to work with. This is where the source language and output language of the bootstrap compiler are chosen. In the case of a "bare machine" (one where no compiler for any language exist) the source and output are written as binary machine code, or may be created by cross compiling on some other machine than the target. Otherwise, the bootstrap compiler is to be written in one of the programming languages which does exis
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https://en.wikipedia.org/wiki/Bulletin%20of%20the%20Irish%20Biogeographical%20Society
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The Bulletin of the Irish Biogeographical Society (, ) publishes many scientific papers on entomology and also entomological catalogues as Occasional Supplements. A full indexed list is provided on the website.
External links
Website of The Irish Biogeographical Society
Biology journals
Entomology journals and magazines
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https://en.wikipedia.org/wiki/Christos%20V.%20Massalas
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Christos V. Massalas is a Greek academic working in the field of mathematics and materials science. He is widely published and has held senior positions at the University of Ioannina and the University of Western Macedonia.
Biography
Massalas was born in Ioannina, Greece. After graduating as a civil engineer, Massalas continued his education with a diploma degree in mathematics (MSc, PhD, habilitation in mechanics). During his education he obtained scholarships from the Polytechnic Institute of Brooklyn, the Fulbright Foundation and UNESCO. He worked as a professor in the Department of Mathematics until 2000 when he was appointed professor of mechanics of materials at the Department of Materials Science in the University of Ioannina. Massalas has worked as a visiting professor at Trinity College, Dublin (1989–1990). He is a vice-director of the Institute B.R.I. and is a member of the scientific committee of Onassis Foundation Science Lectures. He is the author of several books, monographs and more than 100 research papers. His administrative course started in 1992 as chairman of the Department of Mathematics and was followed as vice-rector (1994–1997) at the University of Ioannina, rector (1997–2003) and the following three years (2003–2006) vice-rector of the university as well as the president of the University of Western Macedonia, Greece (2003-). In addition, he is the chairman of the Board of Higher Education (SAPE).
References
Year of birth missing (living people)
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https://en.wikipedia.org/wiki/Alston%20Scott%20Householder
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Alston Scott Householder (5 May 1904 – 4 July 1993) was an American mathematician who specialized in mathematical biology and numerical analysis.
He is the inventor of the Householder transformation and of Householder's method.
Career
Householder was born in Rockford, Illinois, USA. He received a BA in philosophy from the Northwestern University of Evanston, Illinois in 1925, and an MA, also in philosophy, from Cornell University in 1927. He taught mathematics while preparing for his PhD, which was awarded at the University of Chicago in 1937. His thesis dealt with the topic of the calculus of variations.
After receiving his doctorate, Householder concentrated on the field of mathematical biology, working with several other researchers with Nicolas Rashevsky at the University of Chicago.
In 1946, Householder joined the Mathematics Division of the Oak Ridge National Laboratory, where he was appointed chair in 1948; it is during this period that his interests shift toward numerical analysis. In 1969 he left ORNL to become Professor of Mathematics at the University of Tennessee, where he eventually became chairman. In 1974 he retired and went to live in Malibu, California.
Householder contributed in different ways to the organisation of research. He was president of the Society for Industrial and Applied Mathematics (SIAM) and of the Association for Computing Machinery (ACM). He was a member of the redactional committees for Psychometrika, Numerische Mathematik, Linear A
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https://en.wikipedia.org/wiki/Byron%20Halsted
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Byron David Halsted (June 7, 1852 – August 28, 1918) was an American botanist and plant pathologist.
Halsted was born at Venice, New York. He studied at Michigan State University and at Harvard (D.Sc., 1879).
In 1885, he began teaching botany at Iowa State and in 1889, he moved on to Rutgers in New Jersey.
In addition to his writings on biology and agriculture, Halsted was known for his book, Barn Plans and Outbuildings (New York: Orange Judd Co., 1894).
Halsted was an uncle of plant explorer David Fairchild who studied with him in Iowa and New Jersey.
'
References
External links
1852 births
1918 deaths
Michigan State University alumni
Harvard University alumni
Iowa State University faculty
Rutgers University faculty
American botanists
American phytopathologists
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https://en.wikipedia.org/wiki/Taylor%20number
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In fluid dynamics, the Taylor number (Ta) is a dimensionless quantity that characterizes the importance of centrifugal "forces" or so-called inertial forces due to rotation of a fluid about an axis, relative to viscous forces.
In 1923 Geoffrey Ingram Taylor introduced this quantity in his article on the stability of flow.
The typical context of the Taylor number is in characterization of the Couette flow between rotating colinear cylinders or rotating concentric spheres. In the case of a system which is not rotating uniformly, such as the case of cylindrical Couette flow, where the outer cylinder is stationary and the inner cylinder is rotating, inertial forces will often tend to destabilize a system, whereas viscous forces tend to stabilize a system and damp out perturbations and turbulence.
On the other hand, in other cases the effect of rotation can be stabilizing. For example, in the case of cylindrical Couette flow with positive Rayleigh discriminant, there are no axisymmetric instabilities. Another example is a bucket of water that is rotating uniformly (i.e. undergoing solid body rotation). Here the fluid is subject to the Taylor-Proudman theorem which says that small motions will tend to produce purely two-dimensional perturbations to the overall rotational flow. However, in this case the effects of rotation and viscosity are usually characterized by the Ekman number and the Rossby number rather than by the Taylor number.
There are various definitions of the Tay
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https://en.wikipedia.org/wiki/Taylor%E2%80%93Couette%20flow
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In fluid dynamics, the Taylor–Couette flow consists of a viscous fluid confined in the gap between two rotating cylinders. For low angular velocities, measured by the Reynolds number Re, the flow is steady and purely azimuthal. This basic state is known as circular Couette flow, after Maurice Marie Alfred Couette, who used this experimental device as a means to measure viscosity. Sir Geoffrey Ingram Taylor investigated the stability of Couette flow in a ground-breaking paper. Taylor's paper became a cornerstone in the development of hydrodynamic stability theory and demonstrated that the no-slip condition, which was in dispute by the scientific community at the time, was the correct boundary condition for viscous flows at a solid boundary.
Taylor showed that when the angular velocity of the inner cylinder is increased above a certain threshold, Couette flow becomes unstable and a secondary steady state characterized by axisymmetric toroidal vortices, known as Taylor vortex flow, emerges. Subsequently, upon increasing the angular speed of the cylinder the system undergoes a progression of instabilities which lead to states with greater spatio-temporal complexity, with the next state being called wavy vortex flow. If the two cylinders rotate in opposite sense then spiral vortex flow arises. Beyond a certain Reynolds number there is the onset of turbulence.
Circular Couette flow has wide applications ranging from desalination to magnetohydrodynamics and also in viscosimetr
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https://en.wikipedia.org/wiki/Nancy%20Lynch
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Nancy Ann Lynch (born January 19, 1948) is a computer scientist affiliated with the Massachusetts Institute of Technology. She is the NEC Professor of Software Science and Engineering in the EECS department and heads the "Theory of Distributed Systems" research group at MIT's Computer Science and Artificial Intelligence Laboratory.
Education and early life
Lynch was born in Brooklyn, and her academic training was in mathematics. She attended Brooklyn College and MIT, where she received her Ph.D. in 1972 under the supervision of Albert R. Meyer.
Work
She served on the math and computer science faculty at several other universities, including Tufts University, the University of Southern California, Florida International University, and the Georgia Institute of Technology (Georgia Tech), prior to joining the MIT faculty in 1982. Since then, she has been working on applying mathematics to the tasks of understanding and constructing complex distributed systems.
Her 1985 work with Michael J. Fischer and Mike Paterson on consensus problems received the PODC Influential-Paper Award in 2001. Their work showed that in an asynchronous distributed system, consensus is impossible if there is one processor that crashes. On their contribution, Jennifer Welch wrote that "this result has had a monumental impact in distributed computing, both theory and practice. Systems designers were motivated to clarify their claims concerning under what circumstances the systems work."
She is the autho
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https://en.wikipedia.org/wiki/Hollow-cathode%20lamp
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A hollow-cathode lamp (HCL) is type of cold cathode lamp used in physics and chemistry as a spectral line source (e.g. for atomic absorption spectrometers) and as a frequency tuner for light sources such as lasers. An HCL takes advantage of the hollow cathode effect, which causes conduction at a lower voltage and with more current than a cold cathode lamp that does not have a hollow cathode.
An HCL usually consists of a glass tube containing a cathode, an anode, and a buffer gas (usually a noble gas). A large voltage across the anode and cathode will cause the buffer gas to ionize, creating a plasma. The buffer gas ions will then be accelerated into the cathode, sputtering off atoms from the cathode. Both the buffer gas and the sputtered cathode atoms will in turn be excited by collisions with other atoms/particles in the plasma. As these excited atoms decay to lower states, they will emit photons. These photons will then excite the atoms in the sample, which will release their own photons and be used to generate data.
An HCL can also be used to tune light sources to a specific atomic transition by making use of the optogalvanic effect, which is a result of direct or indirect photoionization. By shining the light source into the HCL, one can excite or even eject electrons (directly photoionize) from the atoms inside the lamp, so long as the light source includes frequencies corresponding to the right atomic transitions. Indirect photoionization can then occur when el
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https://en.wikipedia.org/wiki/Pierre%20Dusart
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Pierre Dusart is a French mathematician at the Université de Limoges who specializes in number theory.
He has published in several countries, specially in South Korea, with his colleague Damien Sauveron who is associate professor in Computer Sciences at the Université de Limoges.
External links
Résumé and thesis: (French)
"The kth prime is greater than k(ln k + ln ln k-1) for k>=2". Mathematics of Computation 68 (1999), pp. 411–415.
"ESTIMATES OF SOME FUNCTIONS OVER PRIMES".
Notes and references
French mathematicians
Living people
Year of birth missing (living people)
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https://en.wikipedia.org/wiki/Ronald%20Rivlin
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Ronald Samuel Rivlin (6 May 1915 in London – 4 October 2005) was a British-American physicist, mathematician, rheologist and a noted expert on rubber.
Life
Rivlin was born in London in 1915. He studied physics and mathematics at St John's College, Cambridge, being awarded a BA in 1937 and a ScD in 1952. He worked for the General Electric Company, then the UK Ministry of Aircraft Production, then the British Rubber Producers Research Association, to which he was recruited to at the suggestion of L. R. G. Treloar by John Wilson, over a “lavish meal” and game of pool. This included one sabbatical year at the National Bureau of Standards, USA. His post at the BRPRA was the start of his interest in rubber.
In 1953 he took up the post of Professor of Applied Mathematics at Brown University, moving to Lehigh University in 1967 to become director of the Center for the Application of Mathematics until his retirement in 1980. He married Violet LoRusso in 1948 (they had a son, John) and became an American citizen in 1955.
Work
His work began with his 1944 observation that "although very little force is required to detach Scotch tape from an adherend, the work expended in doing so is very large". This is from the elastic effects of the adhesive, on which he commented even if "one idealized the adhesive as a perfectly elastic material there appeared to be no body of mathematical theory which would provide a basis for calculations". Existing theories were only on very small deformat
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https://en.wikipedia.org/wiki/Long%20branch%20attraction
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In phylogenetics, long branch attraction (LBA) is a form of systematic error whereby distantly related lineages are incorrectly inferred to be closely related. LBA arises when the amount of molecular or morphological change accumulated within a lineage is sufficient to cause that lineage to appear similar (thus closely related) to another long-branched lineage, solely because they have both undergone a large amount of change, rather than because they are related by descent. Such bias is more common when the overall divergence of some taxa results in long branches within a phylogeny. Long branches are often attracted to the base of a phylogenetic tree, because the lineage included to represent an outgroup is often also long-branched. The frequency of true LBA is unclear and often debated, and some authors view it as untestable and therefore irrelevant to empirical phylogenetic inference. Although often viewed as a failing of parsimony-based methodology, LBA could in principle result from a variety of scenarios and be inferred under multiple analytical paradigms.
Causes
LBA was first recognized as problematic when analyzing discrete morphological character sets under parsimony criteria, however Maximum Likelihood analyses of DNA or protein sequences are also susceptible. A simple hypothetical example can be found in Felsenstein 1978 where it is demonstrated that for certain unknown "true" trees, some methods can show bias for grouping long branches, ultimately resulting in th
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https://en.wikipedia.org/wiki/William%20L.%20Burke
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William Lionel Burke (July 1941 – July 1996) was an astronomy, astrophysics, and physics professor at UC Santa Cruz. He is also the author of Spacetime, Geometry, Cosmology (), and of Applied differential geometry (), a text expounding the virtues of differential forms over vector calculus for theoretical physics.
Born in Bennington, Vermont, Burke obtained his Bachelor of Science degree from Caltech in 1963. His 1969 doctoral thesis, also at Caltech and supervised by Kip Thorne, Richard Feynman, and John Wheeler, was entitled The Coupling of Gravitational Radiation to Nonrelativistic Sources. His discovery of the Burke Potential, an aspect of gravitation overlooked by Einstein himself, dates from this period. He became a full professor at UCSC in 1988.
Burke is also known as the godfather of the Santa Cruz "Chaos Cabal" also known as the dynamical systems collective, that nurtured the seminal work of MacArthur Fellow Robert Shaw, Norman Packard, Doyne Farmer and James P. Crutchfield. In Tom Bass' book The Eudaemonic Pie, Burke prided himself for his Rubik's Cube costume at the end of the book which kept his identity concealed from his students.
An avid hiker, climber, skier, sailor, wind surfer, and Go player, Bill Burke died from complications due to a cervical fracture sustained in an automobile accident. Bill's understanding of science is paraphrased by his thinking: "Never descend the Grand Canyon with less than two geologists."
Bill was married and then divorced fro
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https://en.wikipedia.org/wiki/Artin%20approximation%20theorem
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In mathematics, the Artin approximation theorem is a fundamental result of in deformation theory which implies that formal power series with coefficients in a field k are well-approximated by the algebraic functions on k.
More precisely, Artin proved two such theorems: one, in 1968, on approximation of complex analytic solutions by formal solutions (in the case ); and an algebraic version of this theorem in 1969.
Statement of the theorem
Let denote a collection of n indeterminates, the ring of formal power series with indeterminates over a field k, and a different set of indeterminates. Let
be a system of polynomial equations in , and c a positive integer. Then given a formal power series solution , there is an algebraic solution consisting of algebraic functions (more precisely, algebraic power series) such that
Discussion
Given any desired positive integer c, this theorem shows that one can find an algebraic solution approximating a formal power series solution up to the degree specified by c. This leads to theorems that deduce the existence of certain formal moduli spaces of deformations as schemes. See also: Artin's criterion.
Alternative statement
The following alternative statement is given in Theorem 1.12 of .
Let be a field or an excellent discrete valuation ring, let be the henselization at a prime ideal of an -algebra of finite type, let m be a proper ideal of , let be the m-adic completion of , and let
be a functor sending filtered colimits to fi
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https://en.wikipedia.org/wiki/Potential%20%28disambiguation%29
|
Potential generally refers to a currently unrealized ability, in a wide variety of fields from physics to the social sciences.
Mathematics and physics
Scalar potential, a scalar field whose gradient is a given vector field
Vector potential, a vector field whose curl is a given vector field
Potential function (disambiguation)
Potential variable (Boolean differential calculus)
Potential energy, the energy possessed by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors
Magnetic vector potential
Magnetic scalar potential (ψ)
Electric potential, the amount of work needed to move a unit positive charge from a reference point to a specific point inside the field without producing any acceleration
Electromagnetic four-potential, a relativistic vector function from which the electromagnetic field can be derived
Coulomb potential
Van der Waals force, distance-dependent interactions between atoms or molecules
Lennard-Jones potential, a mathematical model that approximates the interaction between a pair of neutral atoms or molecules.
Yukawa potential, a potential in particle physics which may arise from the exchange of a massive scalar field
Gravitational potential
Biology
Action potential, occurs when the membrane potential of a specific axon location rapidly rises and falls: this depolarisation then causes adjacent locations to similarly depolarise
Membrane potential, the difference in electric
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https://en.wikipedia.org/wiki/Peter%20Moore%20%28chemist%29
|
Peter B. Moore (born October 15, 1939) is Sterling Professor emeritus of Chemistry, Professor of Molecular Biophysics and Biochemistry at Yale University. He has dedicated his entire career to understanding the structure, function, and mechanism of the ribosome.
Moore was born in Boston, Massachusetts, in 1939 to Laura Bartlett Moore and Francis Daniels Moore. He received his B.S. degree in biophysics from Yale University in 1961, and his Ph.D. in biophysics from Harvard University in 1966, where he worked in the laboratory of James D. Watson. Prior to attending Yale, Moore graduated from Milton Academy, a prestigious college preparatory school in Milton, Massachusetts, where he was elected to the Cum Laude Society. As a postdoctoral fellow and a sabbatical visitor, he has done research at the University of Geneva, Switzerland (with A. Tissieres), at the Medical Research Council Laboratory of Molecular Biology, Cambridge, England (with Hugh E. Huxley), and at the University of Oxford, England.
He is a fellow of the American Association for the Advancement of Science and of the Biophysical Society, and was elected to the National Academy of Sciences in 1997. He is a member of the American Society of Biochemistry and Molecular Biology, Sigma Xi, American Chemical Society, New York Academy of Sciences, RNA Society and the Connecticut Academy of Science and Engineering. He has served on numerous advisory committees for the Department of Energy, Brookhaven National Laboratory, a
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https://en.wikipedia.org/wiki/Glossary%20of%20category%20theory
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This is a glossary of properties and concepts in category theory in mathematics. (see also Outline of category theory.)
Notes on foundations: In many expositions (e.g., Vistoli), the set-theoretic issues are ignored; this means, for instance, that one does not distinguish between small and large categories and that one can arbitrarily form a localization of a category. Like those expositions, this glossary also generally ignores the set-theoretic issues, except when they are relevant (e.g., the discussion on accessibility.)
Especially for higher categories, the concepts from algebraic topology are also used in the category theory. For that see also glossary of algebraic topology.
The notations and the conventions used throughout the article are:
[n] = {0, 1, 2, …, n}, which is viewed as a category (by writing .)
Cat, the category of (small) categories, where the objects are categories (which are small with respect to some universe) and the morphisms functors.
Fct(C, D), the functor category: the category of functors from a category C to a category D.
Set, the category of (small) sets.
sSet, the category of simplicial sets.
"weak" instead of "strict" is given the default status; e.g., "n-category" means "weak n-category", not the strict one, by default.
By an ∞-category, we mean a quasi-category, the most popular model, unless other models are being discussed.
The number zero 0 is a natural number.
A
B
C
D
E
F
G
H
I
K
L
M
N
O
P
Q
R
S
T
U
W
Y
Z
Notes
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https://en.wikipedia.org/wiki/Vec
|
Vec may mean:
Mathematics:
vec(A), the vectorization of a matrix A.
Vec denotes the category of vector spaces over the reals.
Other:
Venetian language (Vèneto), language code.
Vecuronium, a muscle relaxant.
vec, a sentient moravec robot from the Orion's Arm Universe Project (see also Moravec_(robot))
See also
VEC (disambiguation)
|
https://en.wikipedia.org/wiki/Isochore
|
Isochore may refer to:
Isochoric process, in thermodynamics
Isochore (genetics)
Isochore map, in geology
Isochore, in chemistry as a line representing the variation of pressure with temperature when the volume of the substance operated on is constant. See Isochoric process
|
https://en.wikipedia.org/wiki/Titus%20Burckhardt
|
Titus Burckhardt (24 October 1908 – 15 January 1984) was a Swiss writer and a leading member of the Perennialist or Traditionalist School. He was the author of numerous works on metaphysics, cosmology, anthropology, esoterism, alchemy, Sufism, symbolism and sacred art.
Life
Scion of a patrician family of Basel, Switzerland, Titus Burckhardt was the son of the sculptor Carl Burckhardt (1878–1923) and the grand-nephew of Jacob Burckhardt (1818–1897), an art historian and Renaissance specialist. His genealogical tree also includes John Lewis Burckhardt (1784–1817), the explorer who discovered the Nabatean city of Petra and the Egyptian temples of Abu Simbel. He was born in Florence, Italy, on October 24, 1908. The following year his family settled in Basel. He attended the same primary school as Frithjof Schuon, who became a lifelong friend. In 1920, his family left Basel for Ligornetto in the Swiss canton of Ticino, where his father died three years later.
Around 1927, Burckhardt began studying painting, sculpture and art history in Munich and Paris. Drawn to a traditional lifestyle that the West could not offer him, he took advantage of a break in his studies to visit Morocco (1928 or 1929), where he dedicated himself to drawing and painting. He was captivated by this sojourn, which marked the beginning of his spiritual quest. On his return, he discovered the works of the French metaphysician René Guénon, in whom "he found the key to the world that had entranced him".
In ea
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https://en.wikipedia.org/wiki/Reversion
|
Reversion may refer to:
Reversion (2012 film), a computer-animated short film
Reversion (2015 film), an American science fiction thriller film
Reversion (genetics), a back mutation
Reversion (law)
Reversion (software development)
Series reversion, in mathematics
See also
Reversal (disambiguation)
Reverse (disambiguation)
Reversis, a card-game
Reverted (film), a 1994 film
|
https://en.wikipedia.org/wiki/Rye%20Neck%20High%20School
|
Rye Neck High School is a public secondary school located in the Village of Mamaroneck, New York and the Town of Rye, New York. It is part of the Rye Neck Union Free School District and is connected to Rye Neck Middle School. Rye Neck High School offers 25 Advanced Placement classes as well as many electives such as robotics, journalism, and video production.
It serves the part of the Village of Mamaroneck that is within the Town of Rye and part of the City of Rye.
Sports
In 2017 the Rye Neck Boys Varsity Soccer team won the Section 1 Class B championship. The team advanced to the regional final, falling to Center Moriches.
Rye Neck High School was ranked #140 on Newsweeks 2015 list of the Best High Schools in America
Rye Neck High School was second runner-up for USA Weekends 2007 "Showstopper Contest" for best high school musical, with their performance of Thoroughly Modern Millie. This beat out over 700 other entries.
Four students from Rye Neck High School competed on The Challenge on News12 Westchester.
Rye Neck Varsity Boys Soccer '09-'10 have won the Section 1 Class B Championship with a 3 to 1 victory over Edgemont but fell to 2–1 loss in their Regional Final, which was the farthest they have been in over a decade.
Rye Neck Varsity Boys Soccer '10-'11 made it to the sectional finals (class B) for the 3rd year in a row.
Rye Neck's High School Mock trial team has won numerous state championships and regional championships in recent years.
In 2020, it was announced that
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https://en.wikipedia.org/wiki/Nils%20L%C3%B6fgren
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Nils Löfgren (18 August 1913 – 21 January 1967) was a Swedish chemist who developed the anaesthetic Lidocaine (under the name Xylocaine) in 1943. At this time, he had recently finished his licentiate degree, and was teaching organic chemistry at the University of Stockholm. He and his co-worker Bengt Lundqvist sold the rights to Xylocaine to the Swedish pharmaceutical company Astra AB.
In 1948, Löfgren completed his doctorate, and the title of his dissertation was Studies on local anesthetics: Xylocaine: a new synthetic drug. He later became professor of organic chemistry at the University of Stockholm.
References
Swedish chemists
20th-century Swedish inventors
1913 births
1967 deaths
20th-century chemists
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https://en.wikipedia.org/wiki/Peek%27s%20law
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In physics, Peek's law defines the electric potential gap necessary for triggering a corona discharge between two wires:
ev is the "visual critical corona voltage" or "corona inception voltage" (CIV), the voltage required to initiate a visible corona discharge between the wires. It is named after Frank William Peek (1881–1933).
mv is an irregularity factor to account for the condition of the wires. For smooth, polished wires, mv = 1. For roughened, dirty or weathered wires, 0.98 to 0.93, and for cables, 0.87 to 0.83, namely the surface irregularities result in diminishing the corona threshold voltage.
r is the radius of the wires in cm.
S is the distance between the center of the wires.
gv is the "visual critical" electric field, and is given by:
δ is the air density factor with respect to SATP (25°C and 76 cmHg):
g0 is the "disruptive electric field."
c is an empirical dimensional constant.
The values for the last two parameters are usually considered to be about 30-32 kV/cm (in air) and 0.301 cm½ respectively. This latter law can be considered to hold also in different setups, where the corresponding voltage is different due to geometric reasons.
References
High Voltage Engineering Fundamentals, E.Kuffel and WS Zaengl, Pergamon Press, p366
Plasma physics equations
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https://en.wikipedia.org/wiki/Indian%20Institute%20of%20Astrophysics
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The Indian Institute of Astrophysics (IIA), with its headquarters in Bengaluru, is an autonomous research institute wholly funded by the Department of Science and Technology, Government of India. IIA conducts research primarily in the areas of astronomy, astrophysics and related fields.
The institute has a network of laboratories and observatories in India, including Kodaikanal (the Kodaikanal Solar Observatory), Kavalur (the Vainu Bappu Observatory), Gauribidanur (the Gauribidanur Radio Observatory), Hanle (the Indian Astronomical Observatory) and Hosakote.
IIA contributed to Astrosat, India's first dedicated multi-wavelength space observatory. The Astrosat project is a collaborative effort of many different research institutions from India. The institute led the development of Ultra-Violet Imaging Telescope (UVIT).
Areas of research
Researchers at IIA work on a diverse set of topics related to Astronomy and Astrophysics. However, the research can be broadly classified under the following areas:
Sun & Solar System
Stellar Astronomy
Galactic Astronomy
Extragalactic Astronomy & Cosmology
Theoretical Astrophysics & Physics
Techniques & Instrumentation
Space Astronomy
History
William Petrie (died: 1816), an officer of the East India Company set up private observatory in his residence located in Egmore, Chennai (formerly Madras), India. The main aim of the observatory, according to Petrie, was
"to provide navigational assistance to the company ships and help determine the
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https://en.wikipedia.org/wiki/Regenesis
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Regenesis or ReGenesis may refer to:
Regeneration (biology), the resenesis of amputated or damaged cells, tissues or even organs.
ReGenesis, a Canadian television series
Regenesis (non-profit organization), an environmental group
Regenesis (novel), by C. J. Cherryh
ReGenesis (band), a Genesis tribute band
X-Men: Regenesis, a Marvel Comics storyline
Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves, a book by George M. Church
Regenesis: Feeding the World Without Devouring the Planet, a 2022 book by George Monbiot
|
https://en.wikipedia.org/wiki/Daniel%20Goldston
|
Daniel Alan Goldston (born January 4, 1954, in Oakland, California) is an American mathematician who specializes in number theory. He is currently a professor of mathematics at San Jose State University.
Early life and education
Daniel Alan Goldston was born on January 4, 1954, in Oakland, California. In 1972, he matriculated to the University of California, Berkeley, where he earned his bachelor's degree and, in 1981, a Ph.D. in mathematics. His doctoral advisor at Berkeley was Russell Sherman Lehman; his dissertation was entitled "Large Differences between Consecutive Prime Numbers".
Career
After earning his doctorate, Goldston worked at the University of Minnesota Duluth and then spent the next academic year (1982–83) at the Institute for Advanced Study (IAS) in Princeton. He has worked at San Jose State University since 1983, save for stints at the IAS (1990), the University of Toronto (1994), and the Mathematical Sciences Research Institute in Berkeley (1999).
Research
In 2009, Goldston, János Pintz, and Cem Yıldırım proved:
where denotes the nth prime number. In other words, for every , there exist infinitely many pairs of consecutive primes and which are closer to each other than the average distance between consecutive primes by a factor of , i.e., . This result was originally reported in 2003 by Goldston and Yıldırım but was later retracted. Then Pintz joined the team and they completed the proof with the GPY sieve.
Recognition
In 2014, Goldston won the Co
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https://en.wikipedia.org/wiki/Yang%E2%80%93Mills%20existence%20and%20mass%20gap
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The Yang–Mills existence and mass gap problem is an unsolved problem in mathematical physics and mathematics, and one of the seven Millennium Prize Problems defined by the Clay Mathematics Institute, which has offered a prize of US$1,000,000 for its solution.
The problem is phrased as follows:
Yang–Mills Existence and Mass Gap. Prove that for any compact simple gauge group G, a non-trivial quantum Yang–Mills theory exists on and has a mass gap Δ > 0. Existence includes establishing axiomatic properties at least as strong as those cited in , and .
In this statement, a quantum Yang–Mills theory is a non-abelian quantum field theory similar to that underlying the Standard Model of particle physics; is Euclidean 4-space; the mass gap Δ is the mass of the least massive particle predicted by the theory.
Therefore, the winner must prove that:
Yang–Mills theory exists and satisfies the standard of rigor that characterizes contemporary mathematical physics, in particular constructive quantum field theory, and
The mass of all particles of the force field predicted by the theory are strictly positive.
For example, in the case of G=SU(3)—the strong nuclear interaction—the winner must prove that glueballs have a lower mass bound, and thus cannot be arbitrarily light.
The general problem of determining the presence of a spectral gap in a system is known to be undecidable.
Background
The problem requires the construction of a QFT satisfying the Wightman axioms and showing the
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https://en.wikipedia.org/wiki/Algebraic%20space
|
In mathematics, algebraic spaces form a generalization of the schemes of algebraic geometry, introduced by Michael Artin for use in deformation theory. Intuitively,
schemes are given by gluing together affine schemes using the Zariski topology, while algebraic spaces are given by gluing together affine schemes using the finer étale topology. Alternatively one can think of schemes as being locally isomorphic to affine schemes in the Zariski topology, while algebraic spaces are locally isomorphic to affine schemes in the étale topology.
The resulting category of algebraic spaces extends the category of schemes and allows one to carry out several natural constructions that are used in the construction of moduli spaces but are not always possible in the smaller category of schemes, such as taking the quotient of a free action by a finite group (cf. the Keel–Mori theorem).
Definition
There are two common ways to define algebraic spaces: they can be defined as either quotients of schemes by etale equivalence relations, or as sheaves on a big etale site that are locally isomorphic to schemes. These two definitions are essentially equivalent.
Algebraic spaces as quotients of schemes
An algebraic space X comprises a scheme U and a closed subscheme R ⊂ U × U satisfying the following two conditions:
1. R is an equivalence relation as a subset of U × U
2. The projections pi: R → U onto each factor are étale maps.
Some authors, such as Knutson, add an extra condition that an algeb
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https://en.wikipedia.org/wiki/James%20Gilbert%20Baker
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James Gilbert Baker (November 11, 1914 – June 29, 2005) was an American astronomer and designer of optics systems.
Biography
He was born in Louisville, Kentucky to Jesse B. Baker and Hattie M. Stallard, the fourth child of that couple. He attended Louisville duPont Manual High School then majored in mathematics at the University of Louisville. During his time at the university, he became interested in astronomy and grinding his own mirrors. In 1931 he helped to form the Louisville Astronomical Society. He graduated with a B.A. in 1935.
He met his future wife, Elizabeth Katherine Breitenstein, while at the university.
Pursuing his interest in astronomy, he studied at the Harvard College Observatory. He earned his M.A. in 1936, gained an appointment as a Junior Fellow of the Harvard Society from 1937 until 1943. It was in 1940 that he developed the Baker-Schmidt telescope, a modification of the schmidt camera. In 1942 he was awarded his PhD in astronomy and astrophysics from Harvard University.
After the start of World War II, he was recruited to be a civilian optical designer for the Army's newly formed aerial reconnaissance branch under Colonel George William Goddard. He would design wide-angle camera systems and test them in unpressurized compartments during test flights. He also became a consultant for the Perkin Elmer Corporation. Following the war he then became an advisor for the Air Force Photographic Laboratory.
Living in Cambridge, Massachusetts, from 1946 until
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https://en.wikipedia.org/wiki/Inseparable
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Inseparable may refer to:
Mathematics
Inseparable differential equation, an ordinary differential equation that cannot be solved by using separation of variables
Inseparable extension, a field extension by elements that do not all satisfy a separable polynomial
Inseparable polynomial, a polynomial that does not have distinct roots in a splitting field
Music
Inseparable (album), by Natalie Cole, 1975
"Inseparable" (song), the title song
Inseparable (EP), by Veridia, 2014
Les inséparables, an album by Corneille, 2011
"Inseperable", a song by Jonas Brothers from Jonas Brothers, 2007
"Inseperable", a song by Mariah Carey from Memoirs of an Imperfect Angel, 2009
Other uses
Inseparable (book), a 2019 sports autobiography by Shaquem Griffin and Shaquill Griffin, with Mark Schlabach
Inseparable (film), a 2011 Chinese film by Dayyan Eng
The Inseparables, a 1929 British film by Adelqui Migliar and John Stafford
Inseparability, in marketing, a quality of services as distinct from goods
|
https://en.wikipedia.org/wiki/Mex%20%28mathematics%29
|
In mathematics, the mex ("minimum excluded value") of a subset of a well-ordered set is the smallest value from the whole set that does not belong to the subset. That is, it is the minimum value of the complement set.
Beyond sets, subclasses of well-ordered classes have minimum excluded values. Minimum excluded values of subclasses of the ordinal numbers are used in combinatorial game theory to assign nim-values to impartial games.
According to the Sprague–Grundy theorem, the nim-value of a game position is the minimum excluded value of the class of values of the positions that can be reached in a single move from the given position.
Minimum excluded values are also used in graph theory, in greedy coloring algorithms. These algorithms typically choose an ordering of the vertices of a graph and choose a numbering of the available vertex colors. They then consider the vertices in order, for each vertex choosing its color to be the minimum excluded value of the set of colors already assigned to its neighbors.
Examples
The following examples all assume that the given set is a subset of the class of ordinal numbers:
where is the limit ordinal for the natural numbers.
Game theory
In the Sprague–Grundy theory the minimum excluded ordinal is used to determine the nimber of a normal-play impartial game. In such a game, either player has the same moves in each position and the last player to move wins. The nimber is equal to 0 for a game that is lost immediately by the first
|
https://en.wikipedia.org/wiki/Robert%20E.%20Horton
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Robert Elmer Horton (May 18, 1875 – April 22, 1945) was an American hydrologist, geomorphologist, civil engineer, and soil scientist, considered by many to be the father of modern American hydrology. An eponymous medal is awarded by the American Geophysical Union (AGU) to recognize outstanding contributions to the field of hydrological geophysics. The AGU Hydrology section (representing about a 3rd of AGU's membership) was formed largely due to his personal property (near New York) that was bequeathed to AGU.
Personal History
Born in Parma, Michigan, he earned his B.S. from Albion College in 1897. After his graduation, he went to work for his uncle, George Rafter, a prominent civil engineer. Rafter had commissioned a weir study, the results of which Horton analyzed and summarized. In 1900, he was appointed New York District Engineer of the United States Geological Survey. In the later part of his career, he went on to be a private consultant in hydrologic science. His consulting practice included scholarly works (printing of technical books translated from other languages, French, German, Italian, Ukrainian) and conducting theoretical and experimental research with an outdoor lab (Horton Hydrological Laboratory) modeled after Cornell's Hydraulic Lab.
Broader Contributions in Hydrology
During his studies of New York streams, Horton determined that the degree to which rainfall could reach the aquifer depended on a certain property of the soil, which he called infiltration c
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https://en.wikipedia.org/wiki/Antimonate
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In chemistry an antimonate is a compound which contains a metallic element, oxygen, and antimony in an oxidation state of +5. These compounds adopt polymeric structures with M-O-Sb linkages. They can be considered to be derivatives of the hypothetical antimonic acid H3SbO4, or combinations of metal oxides and antimony pentoxide, Sb2O5.
Historically these compounds were assumed to be analogous to the phosphates and formulas such as LiSbO3·3H2O and Na2H2Sb2O7·5H2O were used and the compounds described as hydrated meta-antimonates and pyro-antimonates. LiSbO3·3H2O is now known to be LiSb(OH)6 and contain the anion and that Na2H2Sb2O7·5H2O is actually NaSb(OH)6.
Some examples of antimonates and their structures are shown below:
Li3SbO4 has a NaCl superstructure with isolated units.
Sodium antimonate, NaSbO3, has the ilmenite structure, with hexagonal close packed oxide ions with each ion, Na+ and Sb5+ occupying a third of the octahedral sites.
MgSb2O6 has the trirutile structure, which is similar to the rutile structure except that there are two different cations in the lattice.
AlSbO4 has the rutile structure with random occupancy.
Lead antimonate, Pb2Sb2O7, Naples yellow, has the pyrochlore structure.
Calcium antimonate, Ca2Sb2O7, has the weberite structure.
Ferric ortho-antimonate, Fe2O3·Sb2O5 or FeSbO4, has the rutile structure with random occupancy.
Antimonate in chemical nomenclature
IUPAC recommendations are that compounds with anions containing antimony(V) have the a
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https://en.wikipedia.org/wiki/List%20of%20experimental%20errors%20and%20frauds%20in%20physics
|
Experimental science demands repeatability of results but many experiments are not due to fraud or error. The list of papers whose results were later retracted or discredited, thus leading to invalid science is growing. Some errors are introduced when the experimenter's desire for a certain result unconsciously influences selection of data (a problem which is possible to avoid in some cases with double-blind protocols). There have also been cases of deliberate scientific misconduct.
Famous experimental errors
N-rays (1903)
A reported faint visual effect that experimenters could still "see" even when the supposed causative element in their apparatus had been secretly disconnected.
Claimed experimental disproof of special relativity (1906)
Published in Annalen der Physik and said to be the first journal paper to cite Einstein's 1905 electrodynamics paper. Walter Kaufmann – stated that his results were not compatible with special relativity. According to Gerald Holton, it took a decade for the shortcomings of Kaufmann's test to be realised: during this time, critics of special relativity were able to claim that the theory was invalidated by the available experimental evidence.
Premature verification of the gravitational redshift effect (1924)
A number of earlier experimenters claimed to have found the presence or lack of gravitational redshift, but Walter Sydney Adams's result was supposed to have settled the issue. Unfortunately the measurement and the prediction were both
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https://en.wikipedia.org/wiki/Bumping
|
Bumping may refer to:
Processes
Bumping (chemistry), the irregular boiling of a liquid
Lock bumping, a lock picking technique
Thread bumping on an Internet forum
Places
Bumping Lake, Washington state, United States
Bumping River, which flows into Bumping Lake
See also
Bump (disambiguation)
|
https://en.wikipedia.org/wiki/Nicholas%20C.%20Handy
|
Nicholas Charles Handy (17 June 1941 – 2 October 2012) was a British theoretical chemist. He retired as Professor of quantum chemistry at the University of Cambridge in September 2004.
Education and early life
Handy was born in Wiltshire, England and educated at Clayesmore School. He studied the Mathematical Tripos at the University of Cambridge and completed his PhD on theoretical chemistry supervised by Samuel Francis Boys.
Research
Handy wrote 320 scientific papers published in physical and theoretical chemistry journals.
Handy developed several methods in quantum chemistry and theoretical spectroscopy. His contributions have helped greatly to the understanding of:
the transcorrelated method
the long range behaviour of Hartree–Fock orbitals
semiclassical methods for vibrational energies
the variational method for rovibrational wave-functions (in normal mode and internal coordinates)
Full configuration interaction with Slater determinants (benchmark studies)
convergence of the Møller–Plesset series
the reaction path Hamiltonian
Anharmonic spectroscopic and thermodynamic properties using higher derivative methods
Brueckner-doubles theory
Open shell Møller–Plesset theory
frequency-dependent properties
Density functional theory : quadrature, new functionals and molecular properties.
Awards and honours
Handy was elected a Fellow of the Royal Society (FRS) in 1990. He was awarded the Leverhulme Medal in 2002 and was a member of the International Academy of Quan
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