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arXiv · 2504.21811

Coarse Baum-Connes and warped cones: failure of surjectivity in odd degree

Christos Kitsios·Thomas Schick·Federico Vigolo
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Abstract

We prove a conjecture of Roe by constructing unified warped cones that violate the coarse Baum-Connes conjecture. Interestingly, the reason for this is probably not what Roe expected, as the obstruction arises in odd rather than even degree.

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Christos Kitsios, Thomas Schick, Federico Vigolo. 2025-05-22. Coarse Baum-Connes and warped cones: failure of surjectivity in odd degree. https://arxiv.org/abs/2504.21811

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