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AF-equivalence relations and their cocycles

Jean Renault
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Abstract

After a review of some of the main results about hyperfinite equivalence relations and their cocycles in the measured setting, we give a definition of a topological AF-equivalence relation. We show that every cocycle is cohomologous to a quasi-product cocycle. We then study the problem of determining the quasi-invariant probability measures admitting a given cocycle as their Radon-Nikodym derivative.

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Jean Renault. 2001-11-15. AF-equivalence relations and their cocycles. https://arxiv.org/abs/math/0111182

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