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arXiv · 2502.01497

Branched coarse coverings and transfer maps

Ulrich Bunke
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Abstract

We introduce the concepts of branched coarse coverings and transfers between coarse homology theories along them. We show that various versions of coarse $K$-homology theories admit the additional structure of transfers. We show versions of Atiyah's $L^{2}$-index theorem in coarse homotopy theory and apply them to give a new argument for the corresponding step in Higson's counterexample to the coarse Baum-Connes conjecture.

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Ulrich Bunke. 2025-02-03. Branched coarse coverings and transfer maps. https://arxiv.org/abs/2502.01497

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