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arXiv · 2311.15409

A non-uniformly inner amenable group

Isaac Goldbring
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Abstract

We provide an example of two elementarily equivalent countable ICC groups $G$ and $H$ such that $G$ is amenable and $H$ is not inner amenable. As a result, we provide the first example of elementarily equivalent groups whose group von Neumann algebras are not elementarily equivalent, answering a question asked by many researchers.

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Isaac Goldbring. 2023-11-26. A non-uniformly inner amenable group. https://arxiv.org/abs/2311.15409

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