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arXiv · 1411.4093

Maximal amenable von Neumann subalgebras arising from maximal amenable subgroups

Rémi Boutonnet·Alessandro Carderi
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Abstract

We provide a general criterion to deduce maximal amenability of von Neumann subalgebras $L\Lambda \subset L\Gamma$ arising from amenable subgroups $\Lambda$ of discrete countable groups $\Gamma$. The criterion is expressed in terms of $\Lambda$-invariant measures on some compact $\Gamma$-space. The strategy of proof is different from S. Popa's approach to maximal amenability via central sequences [Po83], and relies on elementary computations in a crossed-product C*-algebra.

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BibTeXRIS

Rémi Boutonnet, Alessandro Carderi. 2014-11-15. Maximal amenable von Neumann subalgebras arising from maximal amenable subgroups. https://arxiv.org/abs/1411.4093

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