Finite invariant measures on flows

Wong, Robert S. Y.

doi:10.1090/S0002-9939-1992-1059639-0

Finite invariant measures on flows
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by Robert S. Y. Wong

Proc. Amer. Math. Soc. 114 (1992), 167-170

DOI: https://doi.org/10.1090/S0002-9939-1992-1059639-0

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Abstract:

We prove that an ergodic flow admits a finite invariant measure if and only if the Kreiger factor whose flow of weights is the flow contains a ${\text {III}_1}$ subfactor which is the range of a faithful normal semifinite conditional expectation.

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