Deformation of algebras associated with group cocycles

Makoto Yamashita

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arXiv · 1107.2512

Deformation of algebras associated with group cocycles

Makoto Yamashita

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Abstract

We study deformation of algebras with coaction symmetry of reduced algebra of discrete groups, where the deformation parameter is given continuous family of group $2$-cocycles. When the group satisfies the Baum-Connes conjecture with coefficients, we obtain isomorphism of K-groups of the deformed algebras. This extends both the $\theta$-deformation of Rieffel on $\mathbb T^n$-actions, and a recent result of Echterhoff, L\"{u}ck, Phillips, and Walters on the K-groups on the twisted group algebras.

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Makoto Yamashita. 2011-07-13. Deformation of algebras associated with group cocycles. https://arxiv.org/abs/1107.2512

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