In the mathematical field of order theory, an ultrafilter on a given partially ordered set (poset) P is a certain subset of P, namely a maximal filter on P, that is, a proper filter on P that cannot be enlarged to a bigger proper filter on P.
In geometry, the convex hull or convex envelope or convex closure of a shape is the smallest convex set that contains it. The convex hull may be defined either as the intersection of all convex sets containing a given subset of a Euclidean space, or equivalently as the set of all convex combinations of points in the subset. For a bounded subset of the plane, the convex hull may be visualized as the shape enclosed by a rubber band stretched around the subset.
In mathematics, G2 is the name of three simple Lie groups (a complex form, a compact real form and a split real form), their Lie algebras as well as some algebraic groups. They are the smallest of the five exceptional simple Lie groups. G2 has rank 2 and dimension 14. It has two fundamental representations, with dimension 7 and 14.
In functional analysis, a discipline within mathematics, given a C*-algebra A, the Gelfand–Naimark–Segal construction establishes a correspondence between cyclic *-representations of A and certain linear functionals on A. The correspondence is shown by an explicit construction of the *-representation from the state. It is named for Israel Gelfand, Mark Naimark, and Irving Segal.
Paul Richard Halmos was a Hungarian-born American mathematician and statistician who made fundamental advances in the areas of mathematical logic, probability theory, statistics, operator theory, ergodic theory, and functional analysis. He was also recognized as a great mathematical expositor. He has been described as one of The Martians.
In differential geometry, the Atiyah–Singer index theorem, proved by Michael Atiyah and Isadore Singer (1963), states that for an elliptic differential operator on a compact manifold, the analytical index is equal to the topological index. It includes many other theorems, such as the Chern–Gauss–Bonnet theorem and Riemann–Roch theorem, as special cases, and has applications to theoretical physics.
In mathematics, a duality translates concepts, theorems or mathematical structures into other concepts, theorems or structures, in a one-to-one fashion, often by means of an involution operation: if the dual of A is B, then the dual of B is A. Such involutions sometimes have fixed points, so that the dual of A is A itself. For example, Desargues' theorem is self-dual in this sense under the standard duality in projective geometry.
George Whitelaw Mackey was an American mathematician known for his contributions to quantum logic, representation theory, and noncommutative geometry.
Professor Harry Dym is a mathematician at the Weizmann Institute of Science, Israel. Dym's research interests include operator theory, interpolation theory, and inverse problems.
Jacob Theodore "Jack" Schwartz was an American mathematician, computer scientist, and professor of computer science at the New York University Courant Institute of Mathematical Sciences. He was the designer of the SETL programming language and started the NYU Ultracomputer project. He founded the New York University Department of Computer Science, chairing it from 1964 to 1980.
Walter Rudin was an Austrian-American mathematician and professor of Mathematics at the University of Wisconsin–Madison.
Charles Loewner was an American mathematician. His name was Karel Löwner in Czech and Karl Löwner in German.
In the mathematical field of linear algebra and convex analysis, the numerical range or field of values of a complex matrix A is the set
Sigurdur Helgason is an Icelandic mathematician whose research has been devoted to the geometry and analysis on symmetric spaces. In particular he has used new integral geometric methods to establish fundamental existence theorems for differential equations on symmetric spaces as well as some new results on the representations of their isometry groups. He also introduced a Fourier transform on these spaces and proved the principal theorems for this transform, the inversion formula, the Plancherel theorem and the analog of the Paley–Wiener theorem.
In mathematical representation theory, the Eisenstein integral is an integral introduced by Harish-Chandra in the representation theory of semisimple Lie groups, analogous to Eisenstein series in the theory of automorphic forms. Harish-Chandra used Eisenstein integrals to decompose the regular representation of a semisimple Lie group into representations induced from parabolic subgroups. Trombi gave a survey of Harish-Chandra's work on this.
Felix Klein's Encyclopedia of Mathematical Sciences is a German mathematical encyclopedia published in six volumes from 1898 to 1933. Klein and Wilhelm Franz Meyer were organizers of the encyclopedia. Its full title in English is Encyclopedia of Mathematical Sciences Including Their Applications, which is Encyklopädie der mathematischen Wissenschaften mit Einschluss ihrer Anwendungen (EMW). It is 20,000 pages in length and was published by B.G. Teubner Verlag, publisher of Mathematische Annalen.
Bertram John Walsh is an American mathematician, specializing in locally convex spaces, harmonic analysis, and partial differential equations.
Roger David Nussbaum is an American mathematician, specializing in nonlinear functional analysis and differential equations.
Albert "Tommy" Wilansky was a Canadian-American mathematician, known for introducing Smith numbers.
George James Minty Jr. was an American mathematician, specializing in mathematical analysis and discrete mathematics. He is known for the Klee-Minty cube and the Browder-Minty theorem.
