First integral cohomology group of the pure mapping class group of a non-orientable surface of infinite type

Jesús Hernández Hernández; Cristhian E. Hidber

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arXiv · 2104.02684

First integral cohomology group of the pure mapping class group of a non-orientable surface of infinite type

Jesús Hernández Hernández·Cristhian E. Hidber

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Abstract

In this work we compute the first integral cohomology of the pure mapping class group of a non-orientable surface of infinite topological type and genus at least 3. To this purpose, we also prove several other results already known for orientable surfaces such as the existence of an Alexander method, the fact that the mapping class group is isomorphic to the automorphism group of the curve graph along with the topological rigidity of the curve graph, and the structure of the pure mapping class group as both a Polish group and a semi-direct product.

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Jesús Hernández Hernández, Cristhian E. Hidber. 2021-04-06. First integral cohomology group of the pure mapping class group of a non-orientable surface of infinite type. https://arxiv.org/abs/2104.02684

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