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arXiv · 2609.30872

The homology of $\mathrm{Out}(F_8)$ and $\mathrm{Aut}(F_7)$

Maroš Grego·Tomáš Vítek·Thomas Willwacher
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Abstract

We compute the rational homology of $\mathrm{Out}(F_8)$ and $\mathrm{Aut}(F_7)$, and several related groups. We also show that the Eisenstein classes in $H_7(\mathrm{Aut}(F_5))$ and $H_{11}(\mathrm{Aut}(F_7))$ are zero.

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Maroš Grego, Tomáš Vítek, Thomas Willwacher. 2026-09-25. The homology of $\mathrm{Out}(F_8)$ and $\mathrm{Aut}(F_7)$. https://arxiv.org/abs/2609.30872

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