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Non-K-exact uniform Roe C*-algebras

Published online by Cambridge University Press:  03 August 2010

Ján Špakula*
Affiliation:
Mathematisches Institut, Universität Münster, Einsteinstr. 62, 48149 Münster, Germany, jan.spakula@uni-muenster.de
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Abstract

We prove that uniform Roe C*-algebras C*uX associated to some expander graphs X coming from discrete groups with property (τ) are not K-exact. In particular, we show that this is the case for the expander obtained as Cayley graphs of a sequence of alternating groups (with appropriately chosen generating sets).

Type
Research Article
Copyright
Copyright © ISOPP 2010

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