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arXiv · 0907.2249

Non-K-exact uniform Roe C*-algebras

Jan Spakula
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Abstract

We prove that uniform Roe C*-algebras associated to some expander graphs 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).

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Jan Spakula. 2009-07-13. Non-K-exact uniform Roe C*-algebras. https://arxiv.org/abs/0907.2249

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