Results 71 to 80 of about 119,920 (234)
Splitting the difference: Computations of the Reynolds operator in classical invariant theory
Abstract If G$G$ is a linearly reductive group acting rationally on a polynomial ring S$S$, then the inclusion SG↪S$S^{G} \hookrightarrow S$ possesses a unique G$G$‐equivariant splitting, called the Reynolds operator. We describe algorithms for computing the Reynolds operator for the classical actions as in Weyl's book.
Aryaman Maithani
wiley +1 more source
On stabilizers in finite permutation groups
Abstract Let G$G$ be a permutation group on the finite set Ω$\Omega$. We prove various results about partitions of Ω$\Omega$ whose stabilizers have good properties. In particular, in every solvable permutation group there is a set‐stabilizer whose orbits have length at most 6, which is best possible and answers two questions of Babai.
Luca Sabatini
wiley +1 more source
On contact 3‐manifolds that admit a nonfree toric action
Abstract We classify all contact structures on 3‐manifolds that admit a nonfree toric action, up to contactomorphism, and present them through explicit topological descriptions. Our classification is based on Lerman's classification of toric contact 3‐manifolds up to equivariant contactomorphism [Lerman, J. Symplectic Geom. 1 (2003), 785–828].
Aleksandra Marinković, Laura Starkston
wiley +1 more source
Module structure of Weyl algebras
Abstract The seminal paper (Stafford, J. Lond. Math. Soc. (2) 18 (1978), no. 3, 429–442) was a major step forward in our understanding of Weyl algebras. Beginning with Serre's Theorem on free summands of projective modules and Bass' Stable Range Theorem in commutative algebra, we attempt to trace the origins of this work and explain how it led to ...
Gwyn Bellamy
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The criteria for automorphisms on finite-dimensional algebras
In this paper, we will establish a criterion for automorphisms of finite-dimensional algebras. As an application, we will describe all automorphisms of the single-parameter generalized quaternion algebra. Additionally, we will obtain all automorphisms of
Yanni Yang, Quanguo Chen
doaj +1 more source
An application of the Sakai's theorem to the characterization of H*-algebras
The well-known Sakai's theorem, which states that every derivation acting on a von Neumann algebra is inner, is ,used to obtain a new elegant proof of the Saworotnow's characterization theorem for associative H*-algebras via two-sided H*-algebras.
Borut Zalar
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Coxeter's enumeration of Coxeter groups
Abstract In a short paper that appeared in the Journal of the London Mathematical Society in 1934, H. S. M. Coxeter completed the classification of finite Coxeter groups. In this survey, we describe what Coxeter did in this paper and examine an assortment of topics that illustrate the broad and enduring influence of Coxeter's paper on developments in ...
Bernhard Mühlherr, Richard M. Weiss
wiley +1 more source
C.T.C. Wall's 1964 articles on 4‐manifolds
Abstract I survey C. T. C. Wall's influential papers, ‘Diffeomorphisms of 4‐manifolds’ and ‘On simply‐connected 4‐manifolds’, published in 1964 on pp. 131–149 of volume 39 of the Journal of the London Mathematical Society.
Mark Powell
wiley +1 more source
Rota-Baxter Operators of Weight Zero on CayleyDickson Algebra with Matrix Images
Rota-Baxter operators present a natural generalization of integration by parts formula for the integral operator. We consider Rota-Baxter operators of weight zero on split octonion algebra over a field of characteristic not 2.
A. S. Panasenko
doaj +1 more source
Combination theorems for Wise's power alternative
Abstract We show that Wise's power alternative is stable under certain group constructions, use this to prove the power alternative for new classes of groups and recover known results from a unified perspective. For groups acting on trees, we introduce a dynamical condition that allows us to deduce the power alternative for the group from the power ...
Mark Hagen +2 more
wiley +1 more source

