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arXiv · 2512.14147

On finite local approximations of isometric actions of residually finite groups

Vadim Alekseev·Andreas Thom
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Abstract

We show that any isometric action of a residually finite group admits approximate local finite models. As a consequence, if $G$ is residually finite, every isometric $G$-action embeds isometrically into a metric ultraproduct of finite isometric $G$-actions.

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Vadim Alekseev, Andreas Thom. 2025-12-16. On finite local approximations of isometric actions of residually finite groups. https://arxiv.org/abs/2512.14147

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