On compact uniformly recurrent subgroups
Abstract Let a group Γ act on a paracompact, locally compact, Hausdorff space M by homeomorphisms and let 2 M denote the set of closed subsets of M . We endow 2 M with the Chabauty topology, which is compact and admits a natural Γ-action by homeomorphisms. We show that for every minimal Γ-invariant closed subset $\mathcal{Y}$ of 2 M consisting of compact sets, the union $\bigcup \mathcal{Y}\subset M$ has compact closure. As an application, we deduce that every compact uniformly recurrent subgroup of a locally compact group is contained in a compact normal subgroup. This generalizes a result of Ušakov on compact subgroups whose normalizer is compact.
Authors
- Waltraud Lederle (ORCID: https://orcid.org/0000-0002-0604-1423)
- Gil Goffer (ORCID: https://orcid.org/0000-0002-7749-0496)
- Todor Tsankov
- Pierre‐Emmanuel Caprace (ORCID: https://orcid.org/0000-0001-5294-2006)
Institutions
- Université Claude Bernard Lyon 1 (FR)
- Laboratoire de Mathématiques d'Orsay (FR)
- University of California San Diego (US)
- Institut Camille Jordan (FR)
- Technische Universität Dresden (DE)
Publication Details
- Journal
- Proceedings of the Edinburgh Mathematical Society
- Published
- 2025-10-14
- DOI
- https://doi.org/10.1017/s0013091525100783
- Primary Topic
- Advanced Topology and Set Theory
- Type
- article
- Field-Weighted Citation Impact
- 0.00