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arXiv · 2001.10266

General uniform Roe algebra rigidity

Bruno de Mendonça Braga·Ilijas Farah·Alessandro Vignati
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Abstract

We generalize all known results on rigidity of uniform Roe algebras to the setting of arbitrary uniformly locally finite coarse spaces. For instance, we show that isomorphism between uniform Roe algebras of uniformly locally finite coarse spaces whose uniform Roe algebras contain only compact ghost projections implies that the base spaces are coarsely equivalent. Moreover, if one of the spaces has property A, then the base spaces are bijectively coarsely equivalent. We also provide a characterization for the existence of an embedding onto hereditary subalgebra in terms of the underlying spaces. As an application, we partially answer a question of White and Willett about Cartan subalgebras of uniform Roe algebras.

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Bruno de Mendonça Braga, Ilijas Farah, Alessandro Vignati. 2020-01-28. General uniform Roe algebra rigidity. https://arxiv.org/abs/2001.10266

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