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arXiv · 2307.11529

Coarse equivalence versus bijective coarse equivalence of expander graphs

Florent Baudier·Bruno de Mendonça Braga·Ilijas Farah·Alessandro Vignati·Rufus Willett
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Abstract

We provide a characterization of when a coarse equivalence between coarse disjoint unions of expander graphs is close to a bijective coarse equivalence. We use this to show that if the uniform Roe algebras of coarse disjoint unions of expanders graphs are isomorphic, then the metric spaces must be bijectively coarsely equivalent.

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Florent Baudier, Bruno de Mendonça Braga, Ilijas Farah, Alessandro Vignati, Rufus Willett. 2023-07-21. Coarse equivalence versus bijective coarse equivalence of expander graphs. https://arxiv.org/abs/2307.11529

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