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arXiv · 2603.16022

Compact Invariant Random Subgroups

Tal Cohen·Helge Glöckner·Gil Goffer·Waltraud Lederle
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Abstract

We study ergodic invariant random subgroups that give full measure to the subset of compact subgroups. We show that in real Lie groups, compactly generated $p$-adic Lie groups, locally compact hyperbolic groups and infinitely ended groups they are always contained in a compact normal subgroup. In general $p$-adic Lie groups, we show they are contained in the locally elliptic radical. In totally disconnected locally compact groups, we show they are contained in the intersection of all Levi subgroups of inner automorphisms.

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Tal Cohen, Helge Glöckner, Gil Goffer, Waltraud Lederle. 2026-03-17. Compact Invariant Random Subgroups. https://arxiv.org/abs/2603.16022

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