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arXiv · 2210.11304

Maximal amenable subgroups of arithmetic groups

Vadim Alekseev·Alessandro Carderi
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Abstract

By classifying $S$-maximal amenable subgroups of algebraic groups over a global field of characteristic zero, we obtain a complete classification of maximal amenable subgroups up to commensurability in the respective arithmetic groups. Futhermore, we prove that these commensurably maximal amenable subgroups are singular and therefore give rise to maximal amenable von Neumann subalgebras.

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Vadim Alekseev, Alessandro Carderi. 2022-10-20. Maximal amenable subgroups of arithmetic groups. https://arxiv.org/abs/2210.11304

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