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arXiv · 1307.2016

Smooth crossed products of Rieffel's deformations

Sergey Neshveyev
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Abstract

Assume A is a Frechet algebra equipped with a smooth isometric action of a vector group V, and consider Rieffel's deformation A_J of A. We construct an explicit isomorphism between the smooth crossed products V\ltimes\A_J and V\ltimes\A. When combined with the Elliott-Natsume-Nest isomorphism, this immediately implies that the periodic cyclic cohomology is invariant under deformation. Specializing to the case of smooth subalgebras of C*-algebras, we also get a simple proof of equivalence of Rieffel's and Kasprzak's approaches to deformation.

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BibTeXRIS

Sergey Neshveyev. 2013-11-26. Smooth crossed products of Rieffel's deformations. https://doi.org/10.1007/s11005-013-0675-9

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