A note on minimal models for pmp actions

Andy Zucker

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arXiv · 1903.02251

A note on minimal models for pmp actions

Andy Zucker

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Abstract

Given a countable group $G$, we say that a metrizable flow $Y$ is model-universal if by considering the various invariant measures on $Y$, we can recover every free measure-preserving $G$-system up to isomorphism. Weiss has constructed a minimal model-universal flow. In this note, we provide a new, streamlined construction, allowing us to show that a minimal model-universal flow is far from unique.

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Andy Zucker. 2019-03-06. A note on minimal models for pmp actions. https://arxiv.org/abs/1903.02251

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