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The existence of measures of a given cocycle, I: atomless, ergodic σ-finite measures

Published online by Cambridge University Press:  01 October 2008

BENJAMIN MILLER*
Affiliation:
UCLA Department of Mathematics, 520 Portola Plaza, Los Angeles, CA 90095-1555, USA (email: [email protected])

Abstract

Given a Polish space X, a countable Borel equivalence relation E on X, and a Borel cocycle , we characterize the circumstances under which there is a suitably non-trivial σ-finite measure μ on X such that, for every Borel injection ϕ whose graph is contained in E, ρ−1(x),x)=[d*μ)/](xμ-almost everywhere.

Type
Research Article
Copyright
Copyright © 2008 Cambridge University Press

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