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arXiv · 1504.05615

A non-amenable groupoid whose maximal and reduced $C^*$-algebras are the same

Rufus Willett
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Abstract

We construct a locally compact groupoid with the properties in the title. Our example is based closely on constructions used by Higson, Lafforgue, and Skandalis in their work on counterexamples to the Baum-Connes conjecture. It is a bundle of countable groups over the one point compactification of the natural numbers, and is Hausdorff, second countable and \'{e}tale.

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Rufus Willett. 2015-04-21. A non-amenable groupoid whose maximal and reduced $C^*$-algebras are the same. https://arxiv.org/abs/1504.05615

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