Hyperfinite actions on countable sets and probability measure spaces

Miklos Abert; Gabor Elek

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arXiv · 1105.3200

Hyperfinite actions on countable sets and probability measure spaces

Miklos Abert·Gabor Elek

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Abstract

We introduce the notion of hyperfiniteness for permutation actions of countable groups on countable sets and give a geometric and analytic characterization, similar to the known characterizations for amenable actions. We also answer a question of van Douwen on actions of the free group on two generators on countable sets.

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Miklos Abert, Gabor Elek. 2011-05-16. Hyperfinite actions on countable sets and probability measure spaces. https://arxiv.org/abs/1105.3200

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