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arXiv · 0710.2203

Degree one cohomology with twisted coefficients of the mapping class group

Jørgen Ellegaard Andersen·Rasmus Villemoes
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Abstract

Let $\Gamma$ be the mapping class group of an oriented surface $\Sigma$ of genus g with r boundary components. We prove that the first cohomology group $H^1(\Gamma, O(M_{SL(2, C)})^*)$ is non-trivial, where the coefficient module is the dual of the space of algebraic functions on the $SL(2, C)$ moduli space over $\Sigma$.

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Jørgen Ellegaard Andersen, Rasmus Villemoes. 2007-10-11. Degree one cohomology with twisted coefficients of the mapping class group. https://arxiv.org/abs/0710.2203

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