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arXiv · 2110.09289

Weak amenability of free products of hyperbolic and amenable groups

Ignacio Vergara
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Abstract

We show that, if $G$ is an amenable group and $H$ is a hyperbolic group, then the free product $G\ast H$ is weakly amenable. A key ingredient in the proof is the fact that $G\ast H$ is orbit equivalent to $\mathbb{Z}\ast H$.

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Ignacio Vergara. 2021-10-14. Weak amenability of free products of hyperbolic and amenable groups. https://doi.org/10.1017/s0017089521000458

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