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arXiv · 2610.29879

Roe algebras and coarse index maps for spaces with proper actions of {é}tale groupoids. II

Kai Mao
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Abstract

Building on the Roe algebra framework developed in the first paper of this series, we construct equivariant coarse index maps for locally compact Hausdorff spaces equipped with proper actions of {é}tale groupoids, with coefficients in any separable groupoid C* -algebra. The construction uses the coarse structures determined by the groupoid action and requires no choice of metric. By identifying Roe algebras of canonical modules with reduced crossed products, we prove that the Baum-Connes assembly map with coefficients factors through the coarse index map.

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BibTeXRIS

Kai Mao. 2026-10-21. Roe algebras and coarse index maps for spaces with proper actions of {é}tale groupoids. II. https://arxiv.org/abs/2610.29879

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