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arXiv · 1307.7539

Stabilizer Rigidity in Irreducible Group Actions

Yair Hartman·Omer Tamuz
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Abstract

We consider irreducible actions of locally compact product groups, and of higher rank semi-simple Lie groups. Using the intermediate factor theorems of Bader-Shalom and Nevo-Zimmer, we show that the action stabilizers, and all irreducible invariant random subgroups, are co-amenable in their normal closure. As a consequence, we derive rigidity results on irreducible actions that generalize and strengthen the results of Bader-Shalom and Stuck-Zimmer.

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Yair Hartman, Omer Tamuz. 2016-10-22. Stabilizer Rigidity in Irreducible Group Actions. https://doi.org/10.1007/s11856-016-1424-4

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