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arXiv · 1907.03803

Amenability and approximation properties for partial actions and Fell bundles

Fernando Abadie·Alcides Buss·Damián Ferraro
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Abstract

Building on previous papers by Anantharaman-Delaroche (AD) we introduce and study the notion of AD-amenability for partial actions and Fell bundles over discrete groups. We prove that the cross-sectional C*-algebra of a Fell bundle is nuclear if and only if the underlying unit fibre is nuclear and the Fell bundle is AD-amenable. If a partial action is globalisable, then it is AD-amenable if and only if its globalisation is AD-amenable. Moreover, we prove that AD-amenability is preserved by (weak) equivalence of Fell bundles and, using a very recent idea of Ozawa and Suzuki, we show that AD-amenabity is equivalent to an approximation property introduced by Exel.

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Fernando Abadie, Alcides Buss, Damián Ferraro. 2019-07-08. Amenability and approximation properties for partial actions and Fell bundles. https://doi.org/10.1007/s00574-021-00255-8

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