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arXiv · 1512.05570

Reduced C*-algebras of Fell bundles over inverse semigroups

Alcides Buss·Ruy Exel·Ralf Meyer
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Abstract

We construct a weak conditional expectation from the section C*-algebra of a Fell bundle over a unital inverse semigroup to its unit fibre. We use this to define the reduced C*-algebra of the Fell bundle. We study when the reduced C*-algebra for an inverse semigroup action on a groupoid by partial equivalences coincides with the reduced groupoid C*-algebra of the transformation groupoid, giving both positive results and counterexamples.

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Alcides Buss, Ruy Exel, Ralf Meyer. 2017-02-09. Reduced C*-algebras of Fell bundles over inverse semigroups. https://doi.org/10.1007/s11856-017-1516-9

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