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arXiv · 1001.0789

Perfect forms and the cohomology of modular groups

Philippe Elbaz-Vincent·Herbert Gangl·Christophe Soulé
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Abstract

For N=5, 6 and 7, using the classification of perfect quadratic forms, we compute the homology of the Voronoi cell complexes attached to the modular groups SL_N(\Z) and GL_N(\Z). From this we deduce the rational cohomology of those groups.

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Philippe Elbaz-Vincent, Herbert Gangl, Christophe Soulé. 2010-01-05. Perfect forms and the cohomology of modular groups. https://arxiv.org/abs/1001.0789

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