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arXiv · 1601.00576

Compact Support Cohomology of Picard Modular Surfaces

Jukka Keranen
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Abstract

We compute the cohomology with compact supports of a Picard modular surface as a virtual module over the product of the appropriate Galois group and the appropriate Hecke algebra. We use the method developed by Ihara, Langlands, and Kottwitz: comparison of the Grothendieck-Lefschetz formula and the Arthur-Selberg trace formula. Our implementation of this method takes as its starting point the works of Laumon and Morel.

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Jukka Keranen. 2016-01-04. Compact Support Cohomology of Picard Modular Surfaces. https://arxiv.org/abs/1601.00576

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