Hyperfiniteness and the Halmos-rohlin Theorem for Nonsingular Abelian Actions1
نویسندگان
چکیده
Theorem 1. Let the countable abelian group G act nonsingularly and aperiodically on Lebesgue space (X, p.). Then for each finite subset A c G and e > 0 3 finite B c G and F tz X with [bF: bEB} disjoint and PKfl meAB a)F] > 1-e. Theorem 2. Every nonsingular action of a countable abelian group on a Lebesgue space is hyperfinite.
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