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arXiv · 1311.2343

Expanders, exact crossed products, and the Baum-Connes conjecture

Paul Baum·Erik Guentner·Rufus Willett
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Abstract

We reformulate the Baum-Connes conjecture with coefficients by introducing a new crossed product functor for C*-algebras. All confirming examples for the original Baum-Connes conjecture remain confirming examples for the reformulated conjecture, and at present there are no known counterexamples to the reformulated conjecture. Moreover, some of the known expander-based counterexamples to the original Baum-Connes conjecture become confirming examples for our reformulated conjecture.

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Paul Baum, Erik Guentner, Rufus Willett. 2015-04-21. Expanders, exact crossed products, and the Baum-Connes conjecture. https://doi.org/10.2140/akt.2016.1.155

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