• "Witt's theorem" or "the Witt theorem" may also refer to the Bourbaki–Witt fixed point theorem of order theory. In mathematics, Witt's theorem, named...
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  • mathematics, the Bourbaki–Witt theorem in order theory, named after Nicolas Bourbaki and Ernst Witt, is a basic fixed-point theorem for partially ordered...
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  • specifically in the theory of Lie algebras, the Poincaré–Birkhoff–Witt theorem (or PBW theorem) is a result giving an explicit description of the universal...
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  • Thumbnail for Ernst Witt
    in 1991, shortly after his 80th birthday. Witt's work has been highly influential. His invention of the Witt vectors clarifies and generalizes the structure...
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  • (quadratic forms) Witt's theorem (quadratic forms) Artin–Wedderburn theorem (abstract algebra) Artin–Zorn theorem (algebra) Brauer–Cartan–Hua theorem (ring theory)...
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  • the free associative algebra generated by X. By the Poincaré–Birkhoff–Witt theorem it is the "same size" as the symmetric algebra of the free Lie algebra...
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  • fixed-point theorem Banach fixed-point theorem Bekić's theorem Borel fixed-point theorem Bourbaki–Witt theorem Browder fixed-point theorem Brouwer fixed-point...
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  • Poincaré-Bendixson theorem, on the existence of attractors for two-dimensional dynamical systems; Poincaré–Birkhoff–Witt theorem, concerning Lie algebras...
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  • the enveloping algebra. Indeed, it follows from the Poincaré–Birkhoff–Witt theorem (discussed § below) that the elements 1 , e , e 2 , e 3 , … {\displaystyle...
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    the proofs of several theorems of crucial importance, for instance the Hahn–Banach theorem in functional analysis, the theorem that every vector space...
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  • quadratic form Hasse–Minkowski theorem Quadric Ramanujan's ternary quadratic form Square class Witt group Witt's theorem A tradition going back to Gauss...
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  • (Witt geometry) Witt group Witt index Witt polynomial Witt ring Grothendieck-Witt ring Witt scheme Witt's theorem Witt vector Witt vector cohomology...
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  • {\displaystyle {\mathfrak {g}}} , then by the easy part of the Poincaré–Birkhoff–Witt theorem, we can rewrite Z Y α i 1 ⋯ Y α i M {\displaystyle ZY_{\alpha _{i_{1}}}\cdots...
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  • {\displaystyle {\widetilde {C}}=C} . ◻ {\displaystyle \square } The Bourbaki–Witt theorem, together with the Axiom of choice, can be used to prove the Hausdorff...
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  • Poincaré–Birkhoff–Witt theorem states that every Lie algebra embeds into the commutator Lie algebra of its universal enveloping algebra. Ado's theorem states that...
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  • …) of ⊥ (see also the Kleene fixed-point theorem). Another fixed point theorem is the Bourbaki–Witt theorem, stating that if f {\displaystyle f} is a...
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  • Séminaire Nicolas Bourbaki (1960–1969) Bourbaki–Witt theorem Bourbaki–Alaoglu theorem Jacobson–Bourbaki theorem Nikolaos Bourbakis, computer scientist A place...
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  • described above, (1), as a Lie algebra of matrices. The Poincaré–Birkhoff–Witt theorem applies to determine the universal enveloping algebra U ( h n ) {\displaystyle...
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  • Thumbnail for Henri Poincaré
    Poincaré–Birkhoff–Witt theorem: an explicit description of the universal enveloping algebra of a Lie algebra. Poincaré–Bjerknes circulation theorem: theorem about...
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  • filtration on the universal enveloping algebra and the Poincaré–Birkhoff–Witt theorem. Suppose that G is a group and K is a field. Is the group ring R = K[G]...
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    enveloping algebra of a Lie algebra is established by the Poincaré–Birkhoff–Witt theorem. Gröbner bases are also sometimes called standard bases. In physics,...
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  • that it would also follow from the Schreier conjecture (see Witt (1998, p.277) for Witt's unpublished 1937 note about this), but the Schreier conjecture...
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  • later given by Ernst Witt. Witt's proof is sketched below. Alternatively, the theorem is a consequence of the Skolem–Noether theorem by the following argument...
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  • representation theorem Birkhoff's HSP theorem Birkhoff's theorem Birkhoff–Kakutani theorem Pierce–Birkhoff conjecture Pierce–Birkhoff ring Poincaré–Birkhoff–Witt theorem...
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  • be used to perform the commutations required by the Poincaré–Birkhoff–Witt theorem used in the construction of a universal enveloping algebra. As such,...
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  • F^{i+1}} using ⊆ as the ordering. So by a fixed-point theorem (specifically Bourbaki–Witt theorem), there exists a fixed point for this iterative process...
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    U({\mathfrak {g}})=T({\mathfrak {g}})/I} . It satisfies the Poincaré–Birkhoff–Witt theorem: if e 1 , … , e n {\displaystyle e_{1},\ldots ,e_{n}} is a basis for...
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  • Birkhoff's theorem (disambiguation), multiple theorems Birkhoff decomposition, two different decompositions Birkhoff algorithm Poincaré–Birkhoff–Witt theorem This...
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  • condition that the Poincaré–Birkhoff–Witt theorem holds (and, in general, they are necessary conditions for the theorem to hold). Just as for Lie algebras...
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  • Law Field Person(s) Named After Abel's theorem Calculus Niels Henrik Abel Ariadne's thread Computer science Ariadne Amdahl's law Computer science Gene...
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