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arXiv · 2506.10706

Asymptotic and cohomological dimension of surface braid groups and poly-surface groups

Abstract

In this paper, we determine the asymptotic dimension for all surface braid groups -- including those associated with non-orientable and infinite-type surfaces -- as well as for torsion-free poly-finitely generated surface groups. We demonstrate that for both classes, the virtual cohomological dimension and the asymptotic dimension coincide. For poly-finitely generated surface groups and braid groups of finite-type surfaces, our approach establishes that these groups are virtual duality groups in the sense of Bieri-Eckmann. In the case of infinite-type surfaces, the argument is based on the fact that their braid groups are countable and normally poly-free.

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BibTeXRIS

Porfirio L. León Álvarez, Israel Morales. 2025-06-12. Asymptotic and cohomological dimension of surface braid groups and poly-surface groups. https://arxiv.org/abs/2506.10706

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