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arXiv · 1509.05880

A new look at C*-simplicity and the unique trace property of a group

Uffe Haagerup
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Abstract

We characterize when the reduced C*-algebra of a group has unique tracial state, respectively, is simple, in terms of Dixmier-type properties of the group C*-algebra. We also give a simple proof of the recent result by Breuillard, Kalantar, Kennedy and Ozawa that the reduced C*-algebra of a group has unique tracial state if and only if the amenable radical of the group is trivial.

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Uffe Haagerup. 2016-06-12. A new look at C*-simplicity and the unique trace property of a group. https://arxiv.org/abs/1509.05880

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