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arXiv · 2203.01697

Stable cohomology of congruence subgroups

Oscar Randal-Williams
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Abstract

We describe the $\mathbb{F}_p$-cohomology of the congruence subgroups $SL_n(\mathbb{Z}, p^m)$ in degrees $* < p-1$, for all large enough $n$, establishing a formula proposed by F. Calegari. Along the way, we also establish a formula for the stable cohomology of $SL_n(\mathbb{Z}/p)$ with certain twisted coefficients.

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Oscar Randal-Williams. 2022-03-03. Stable cohomology of congruence subgroups. https://arxiv.org/abs/2203.01697

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