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arXiv · 1606.08262

Characterizations of locally finite actions of groups on sets

Eduardo Scarparo
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Abstract

We show that an action of a group on a set $X$ is locally finite if and only if $X$ is not equidecomposable with a proper subset of itself. As a consequence, a group is locally finite if and only if its uniform Roe algebra is finite.

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Eduardo Scarparo. 2016-06-27. Characterizations of locally finite actions of groups on sets. https://doi.org/10.1017/s001708951700009x

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