Weak density of orbit equivalence classes and free products of infinite abelian groups

Moriyama, Takaaki

doi:10.1090/proc/14703

Weak density of orbit equivalence classes and free products of infinite abelian groups
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by Takaaki Moriyama PDF

Proc. Amer. Math. Soc. 148 (2020), 315-324 Request permission

Abstract:

We show that if a countable group $G$ is the free product of infinite abelian groups, then for every free, probability-measure-preserving (p.m.p.) action of $G$, its orbit equivalence class is weakly dense in the space of p.m.p. actions of $G$. This extends Lewis Bowen’s result for free groups.

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