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arXiv · 1708.04105

Opposite algebras of groupoid C*-algebras

Alcides Buss·Aidan Sims
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Abstract

We show that every groupoid C*-algebra is isomorphic to its opposite, and deduce that there exist C*-algebras that are not stably isomorphic to groupoid C*-algebras, though many of them are stably isomorphic to twisted groupoid C*-algebras. We also prove that the opposite algebra of a section algebra of a Fell-bundle over a groupoid is isomorphic to the section algebra of a natural opposite bundle.

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Alcides Buss, Aidan Sims. 2017-08-14. Opposite algebras of groupoid C*-algebras. https://arxiv.org/abs/1708.04105

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