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arXiv · 1910.06900

Growth of cohomology of arithmetic groups and the stable trace formula: the case of $U(2,1)$

Mathilde Gerbelli-Gauthier
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Abstract

We present a strategy to use the stable trace formula to compute growth in the cohomology of cocompact arithmetic lattices in a reductive group $G$. We then implement it in the case where $G = U(2,1)$, using results of Rogwaski. This recovers a result of Marshall.

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Mathilde Gerbelli-Gauthier. 2019-10-15. Growth of cohomology of arithmetic groups and the stable trace formula: the case of $U(2,1)$. https://arxiv.org/abs/1910.06900

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