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arXiv · 1310.5864

Maximal amenable subalgebras of von Neumann algebras associated with hyperbolic groups

Rémi Boutonnet·Alessandro Carderi
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Abstract

We prove that for any infinite, maximal amenable subgroup $H$ in a hyperbolic group $G$, the von Neumann subalgebra $LH$ is maximal amenable inside $LG$. It provides many new, explicit examples of maximal amenable subalgebras in II$_1$ factors. We also prove similar maximal amenability results for direct products of relatively hyperbolic groups and orbit equivalence relations arising from measure-preserving actions of such groups.

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Rémi Boutonnet, Alessandro Carderi. 2013-10-22. Maximal amenable subalgebras of von Neumann algebras associated with hyperbolic groups. https://arxiv.org/abs/1310.5864

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