Abstract
We study cocycles of an ergodic generic countable equivalence relation ℜ modulo meager sets. Two cocycles of ℜ are called weakly equivalent if they are cohomologous up to an element of Aut ℜ. It is proved that two nontransient cocycles with values in an arbitrary countable group are weakly equivalent if and only if their generic Mackey actions are isomorphic.
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Kulagin, V. Classification of cocycles of generic equivalence relations. Isr. J. Math. 152, 83–104 (2006). https://doi.org/10.1007/BF02771977
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DOI: https://doi.org/10.1007/BF02771977