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arXiv · 1608.01331

Invariant random subgroups and action versus representation maximality

Peter J. Burton·Alexander S. Kechris
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Abstract

We show that weak containment of free ergodic measure-preserving actions of $\mathbf{F}_\infty$ is not equivalent to weak containment of the corresponding Koopman representations. This result is based on the construction of an invariant random subgroup of $\mathbf{F}_\infty$ which is supported on the maximal actions.

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Peter J. Burton, Alexander S. Kechris. 2016-08-03. Invariant random subgroups and action versus representation maximality. https://arxiv.org/abs/1608.01331

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