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Non-K-exact uniform Roe C*-algebras

Published online by Cambridge University Press:  03 August 2010

Ján Špakula
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).

Keywords

uniform Roe C*-algebrasK-exactnessexpanders

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Type
Research Article
Information
Journal of K-Theory , Volume 10 , Issue 1 , August 2012 , pp. 191 - 201
Copyright
Copyright © ISOPP 2010

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