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Von Neumann
Von Neumann may refer to: * John von Neumann (1903–1957), a Hungarian American mathematician * Von Neumann family * Von Neumann (surname), a German surname * Von Neumann (crater), a lunar impact crater See also * Von Neumann algebra * Von Neumann architecture * Von Neumann conjecture * Von Neumann entropy * Von Neumann machine (other) * Von Neumann neighborhood * Von Neumann universe {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Von Neumann
John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest coverage of any mathematician of his time and was said to have been "the last representative of the great mathematicians who were equally at home in both pure and applied mathematics". He integrated pure and applied sciences. Von Neumann made major contributions to many fields, including mathematics (foundations of mathematics, measure theory, functional analysis, ergodic theory, group theory, lattice theory, representation theory, operator algebras, matrix theory, geometry, and numerical analysis), physics (quantum mechanics, hydrodynamics, ballistics, nuclear physics and quantum statistical mechanics), economics ( game theory and general equilibrium theory), computing ( Von Neumann architecture, linear programming, numerical meteo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Family
{{lowercase title The von Neumann family (also spelled de Neuman) is a Jewish family that was elevated to the ranks of nobility in Austria-Hungary. History In 1830 Francis II, Holy Roman Emperor created the title Baron of Neumann for Philipp von Neumann. In 1913 Franz Joseph I of Austria elevated three branches of the family to noble rank. One branch of the family, von Neumann de Végvár, were elevated to the rank of baron. The first three members of the family to be created Barons of Végvár were Adolf and Dániel Neumann. Later that year Franz Joseph I elevated Miksa von Neumann to the landed nobility. This branch was given the nobiliary particle and style von Neymann de Margitta. Another branch of the family Neumann von Héthárs were granted the rank of hereditary knight by the emperor. Notable family members * Baron Philipp von Neumann (1781–1851), diplomat * Heinrich Neumann Ritter von Héthárs (1873–1939), otorhinolaryngologist * John von Neumann (1903–1957), ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann (surname)
Neumann is German and Yiddish for "new man", and one of the 20 most common German surnames. People * Von Neumann family, a Jewish Hungarian noble family A–G *Adam Neumann (born 1979), Israeli-born entrepreneur and founder of WeWork *Alfred Neumann (writer), German writer *Alfred Neumann (East Germany), East German politician * Angela von Neumann, American artist *Arthur Henry Neumann, British born hunter and explorer *Bernd Neumann, German politician *Balthasar Neumann (1687–1753), Bohemian German architect *Bernhard Neumann, German-born mathematician *Bernard de Neumann (also Bernhard von Neumann), English mathematician, computer scientist, naval historian *Birthe Neumann, Danish actress *Carl Neumann, German mathematician ** Neumann boundary condition *Caspar Neumann, Prussian clergyman and statistician *Caspar Neumann (chemist), German/Polish chemist and apothecary *Christoph Neumann (born 1964), German politician *Dave Neumann, Canadian politician *Elsa Neumann, Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann (crater)
Von Neumann is a lunar impact crater that lies on the far side of the Moon, in the northern hemisphere, named after polymath John von Neumann. It is nearly attached to the south-southeastern rim of the walled plain Campbell. The crater Ley is attached to the northeastern rim of Von Neumann, and is somewhat overlain by the outer rampart. To the west is the prominent Wiener, and to the south-southwest is Nikolayev. This crater has a wide inner wall with multiple terraces. The width of the inner wall varies around the perimeter, with the widest section to the south. There is some slumping along the inner wall to the northwest where the rim makes its closest approach to Campbell, and the narrow terrain between these two craters is rugged and irregular. But the remaining terrain that surrounds the crater is almost equally rugged. The rim appears somewhat straighter along the southwest side, but is roughly circular elsewhere. The interior floor is nearly flat and level along the wes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Algebra
In mathematics, a von Neumann algebra or W*-algebra is a *-algebra of bounded operators on a Hilbert space that is closed in the weak operator topology and contains the identity operator. It is a special type of C*-algebra. Von Neumann algebras were originally introduced by John von Neumann, motivated by his study of single operators, group representations, ergodic theory and quantum mechanics. His double commutant theorem shows that the analytic definition is equivalent to a purely algebraic definition as an algebra of symmetries. Two basic examples of von Neumann algebras are as follows: *The ring L^\infty(\mathbb R) of essentially bounded measurable functions on the real line is a commutative von Neumann algebra, whose elements act as multiplication operators by pointwise multiplication on the Hilbert space L^2(\mathbb R) of square-integrable functions. *The algebra \mathcal B(\mathcal H) of all bounded operators on a Hilbert space \mathcal H is a von Neumann algebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Architecture
The von Neumann architecture — also known as the von Neumann model or Princeton architecture — is a computer architecture based on a 1945 description by John von Neumann, and by others, in the ''First Draft of a Report on the EDVAC''. The document describes a design architecture for an electronic digital computer with these components: * A processing unit with both an arithmetic logic unit and processor registers * A control unit that includes an instruction register and a program counter * Memory that stores data and instructions * External mass storage * Input and output mechanisms.. The term "von Neumann architecture" has evolved to refer to any stored-program computer in which an instruction fetch and a data operation cannot occur at the same time (since they share a common bus). This is referred to as the von Neumann bottleneck, which often limits the performance of the corresponding system. The design of a von Neumann architecture machine is simpler than in a Harva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Conjecture
In mathematics, the von Neumann conjecture stated that a group ''G'' is non- amenable if and only if ''G'' contains a subgroup that is a free group on two generators. The conjecture was disproved in 1980. In 1929, during his work on the Banach–Tarski paradox, John von Neumann defined the concept of amenable groups and showed that no amenable group contains a free subgroup of rank 2. The suggestion that the converse might hold, that is, that every non-amenable group contains a free subgroup on two generators, was made by a number of different authors in the 1950s and 1960s. Although von Neumann's name is popularly attached to the conjecture, its first written appearance seems to be due to Mahlon Marsh Day in 1957. The Tits alternative is a fundamental theorem which, in particular, establishes the conjecture within the class of linear groups. The historically first potential counterexample is Thompson group ''F''. While its amenability is a wide open problem, the general conjec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Entropy
In physics, the von Neumann entropy, named after John von Neumann, is an extension of the concept of Gibbs entropy from classical statistical mechanics to quantum statistical mechanics. For a quantum-mechanical system described by a density matrix , the von Neumann entropy is : S = - \operatorname(\rho \ln \rho), where \operatorname denotes the trace and ln denotes the (natural) matrix logarithm. If is written in terms of its eigenvectors , 1\rangle, , 2\rangle, , 3\rangle, \dots as : \rho = \sum_j \eta_j \left, j \right\rang \left\lang j \ , then the von Neumann entropy is merely : S = -\sum_j \eta_j \ln \eta_j . In this form, ''S'' can be seen as the information theoretic Shannon entropy. The von Neumann entropy is also used in different forms ( conditional entropies, relative entropies, etc.) in the framework of quantum information theory to characterize the entropy of entanglement. Background John von Neumann established a rigorous mathematical framework for quantum me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Machine (other)
{{disambiguation ...
Von Neumann machine may refer to: * Von Neumann architecture, a conceptual model of nearly all computer architecture * IAS machine, a computer designed in the 1940s based on von Neumann's design * Self-replicating machine, a class of machines that can replicate themselves ** Universal constructor (other) ** Von Neumann probes, hypothetical space probes capable of self-replication ** Nanorobots, capable of self-replication * The Von Neumann cellular automaton Von Neumann cellular automata are the original expression of cellular automata, the development of which was prompted by suggestions made to John von Neumann by his close friend and fellow mathematician Stanislaw Ulam. Their original purpose was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Neighborhood
In cellular automata, the von Neumann neighborhood (or 4-neighborhood) is classically defined on a two-dimensional square lattice and is composed of a central cell and its four adjacent cells. The neighborhood is named after John von Neumann, who used it to define the von Neumann cellular automaton and the von Neumann universal constructor within it. It is one of the two most commonly used neighborhood types for two-dimensional cellular automata, the other one being the Moore neighborhood. This neighbourhood can be used to define the notion of 4-connected pixels in computer graphics.. The von Neumann neighbourhood of a cell is the cell itself and the cells at a Manhattan distance of 1. The concept can be extended to higher dimensions, for example forming a 6-cell octahedral neighborhood for a cubic cellular automaton in three dimensions. Von Neumann neighborhood of range ''r'' An extension of the simple von Neumann neighborhood described above is to take the set of poin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
