Results 21 to 30 of about 16,147,605 (261)
Rapid mixing for compact group extensions of hyperbolic flows [PDF]
In this article, we give explicit conditions for compact group extensions of hyperbolic flows (including geodesic flows on negatively curved manifolds) to exhibit quantifiable rates of mixing (or decay of correlations) with respect to the natural ...
M. Pollicott, Daofei Zhang
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Algorithms for Group Isomorphism via Group Extensions and Cohomology [PDF]
Cybersecurity and Cyberforensics Conference, 2013 The isomorphism problem for groups given by their multiplication tables (GPI) has long been known to be solvable in nO(log n) time, but only recently has there been significant progress towards polynomial time. For example, Babai et al. (ICALP 2012) gave
Joshua A. Grochow, Youming Qiao
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Extensions of group retractions
International Journal of Mathematics and Mathematical Sciences, 1980 In this paper a condition, which is necessary and sufficient, is determined when a retraction of a subgroup H of a torsion-free group G can be extended to a retraction of G.
Richard D. Byrd +3 more
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Gerstenhaber brackets on Hochschild cohomology of quantum symmetric algebras and their group extensions [PDF]
, 2014 We construct chain maps between the bar and Koszul resolutions for a quantum symmetric algebra (skew polynomial ring). This construction uses a recursive technique involving explicit formulae for contracting homotopies. We use these chain maps to compute
S. Witherspoon, Guo-Dong Zhou
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Recurrence and pressure for group extensions [PDF]
Ergodic Theory and Dynamical Systems, 2012 We investigate the thermodynamic formalism for recurrent potentials on group extensions of countable Markov shifts. Our main result characterizes recurrent potentials depending only on the base space, in terms of the existence of a conservative product ...
Johannes Jaerisch
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On Azumaya Galois extensions and skew group rings
International Journal of Mathematics and Mathematical Sciences, 1999 Two characterizations of an Azumaya Galois extension of a ring are given in terms of the Azumaya skew group ring of the Galois group over the extension and a Galois extension of a ring with a special Galois system is determined by the trace of the Galois
George Szeto
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On model-theoretic connected components in some group extensions [PDF]
Journal of Mathematical Logic, 2012 We analyze model-theoretic connected components in extensions of a given group by abelian groups which are defined by means of 2-cocycles with finite image.
Jakub Gismatullin, K. Krupiński
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Skew group rings which are Galois
International Journal of Mathematics and Mathematical Sciences, 2000 Let S*G be a skew group ring of a finite group G over a ring S. It is shown that if S*G is an G′-Galois extension of (S*G)G′, where G′ is the inner automorphism group of S*G induced by the elements in G, then S is a G-Galois extension of SG.
George Szeto, Lianyong Xue
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The Ore Extension of Group-Cograded Hopf Coquasigroups
Mathematics, 2023 The aim of this paper is the Ore extension of group-cograded Hopf coquasigroups. This paper first shows a categorical interpretation and some examples of group-cograded Hopf coquasigroups, and then provides a necessary and sufficient condition for the ...
Lingli Zhu +3 more
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Onto extensions of free groups [PDF]
Groups, Complexity, Cryptology, 2021 An extension of subgroups $H\leqslant K\leqslant F_A$ of the free group of rank $|A|=r\geqslant 2$ is called onto when, for every ambient free basis $A'$, the Stallings graph $\Gamma_{A'}(K)$ is a quotient of $\Gamma_{A'}(H)$.
Sebastià Mijares, Enric Ventura
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