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Related papers: Limit group invariants for non-free Cantor actions

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We present a simple approach to questions of topological orbit equivalence for actions of countable groups on topological and smooth manifolds. For example, for any action of a countable group $\Gamma$ on a topological manifold where the…

Dynamical Systems · Mathematics 2007-05-23 David Fisher , Kevin Whyte

We show that the dynamic asymptotic dimension of a minimal free action of an infinite virtually cyclic group on a compact Hausdorff space is always one. This extends a well-known result of Guentner, Willett, and Yu for minimal free actions…

Dynamical Systems · Mathematics 2023-06-22 Massoud Amini , Kang Li , Damian Sawicki , Ali Shakibazadeh

We consider the action of a noncompact torus H on the compact quotient G/L, where G is a Lie group containing H and L is a uniform lattice in G. Using harmonic analysis on G we prove a formula relating the compact orbits of H to the action…

dg-ga · Mathematics 2008-02-03 Anton Deitmar

We consider expansive group actions on a compact metric space containing a special fixed point denoted by $0$, and endomorphisms of such systems whose forward trajectories are attracted toward $0$. Such endomorphisms are called…

Dynamical Systems · Mathematics 2019-02-18 Ville Salo , Ilkka Törmä

The moduli space for a flat G-bundle over the two-torus is completely determined by its holonomy representation. When G is compact, connected, and simply connected, we show that the moduli space is homeomorphic to a product of two tori mod…

Group Theory · Mathematics 2010-06-22 Kristen A. Nairn

A subgroup $H$ of a group $G$ is confined if the $G$-orbit of $H$ under conjugation is bounded away from the trivial subgroup in the space $\operatorname{Sub}(G)$ of subgroups of $G$. We prove a commutator lemma for confined subgroups. For…

Group Theory · Mathematics 2023-07-06 Adrien Le Boudec , Nicolás Matte Bon

This study describes such a situation that a Cantor set emerges as a result of the exploration of sufficient conditions for the property which is generalized from fundamental chaotic maps, and the Cantor set even guarantees infinitely many…

Chaotic Dynamics · Physics 2015-03-18 Yoshihito Ogasawara , Shin'ichi Oishi

A group is tubular if it acts on a tree with $\mathbb{Z}^2$ vertex stabilizers and $\mathbb{Z}$ edge stabilizers. We prove that a tubular group is virtually special if and only if it acts freely on a locally finite CAT(0) cube complex.…

Group Theory · Mathematics 2016-07-22 Daniel J. Woodhouse

For a non-elementary discrete isometry group $G$ of divergence type acting on a proper geodesic $\delta$-hyperbolic space, we prove that its Patterson measure is quasi-invariant under the normalizer of $G$. As applications of this result,…

Metric Geometry · Mathematics 2019-11-11 Katsuhiko Matsuzaki , Yasuhiro Yabuki , Johannes Jaerisch

In this note, we show that if $G$ is an amenable group acting on a dendrite $X$, then the restriction of $G$ to any minimal set $K$ is equicontinuous, and $K$ is either finite or homeomorphic to the Cantor set.

Dynamical Systems · Mathematics 2020-06-29 Enhui Shi , Xiangdong Ye

Let $\Gamma$ be a finitely generated group and $X$ be a minimal compact $\Gamma$-space. We assume that the $\Gamma$-action is micro-supported, i.e. for every non-empty open subset $U \subseteq X$, there is an element of $\Gamma$ acting…

Group Theory · Mathematics 2021-07-19 Pierre-Emmanuel Caprace , Adrien Le Boudec , Dominik Francoeur

We continue our study of the outer Pinsker factor for probability measure-preserving actions of sofic groups. Using the notion of doubly quenched convergence developed by Austin, we prove that in many cases the outer Pinsker factor of a…

Dynamical Systems · Mathematics 2021-03-26 Ben Hayes

This is the second of two papers but has been written so as to have minimal dependence on the first paper (which is also on this archive). Let G be a group and let M be a CAT(0) proper metric space (e.g. a simply connected complete…

Group Theory · Mathematics 2007-05-23 Robert Bieri , Ross Geoghegan

Despite the great success of using gradient-based controllers to stabilize rigid formations of autonomous agents in the past years, surprising yet intriguing undesirable collective motions have been reported recently when inconsistent…

Robotics · Computer Science 2016-09-22 Hector Garcia de Marina , Ming Cao , Bayu Jayawardhana

We establish character rigidity for all non-uniform higher-rank irreducible lattices in semisimple groups of characteristic other than 2. This implies stabilizer rigidity for probability measure preserving actions and rigidity of invariant…

Group Theory · Mathematics 2025-07-30 Alon Dogon , Michael Glasner , Yuval Gorfine , Liam Hanany , Arie Levit

We construct large families of groups admitting free transitive actions on median spaces. In particular, we construct groups which act freely and transitively on the complete universal real tree with continuum valence such that any subgroup…

Group Theory · Mathematics 2025-07-31 Pénélope Azuelos

We prove that if two topologically free and entropy regular actions of countable sofic groups on compact metrizable spaces are continuously orbit equivalent, and each group either (i) contains a w-normal amenable subgroup which is neither…

Dynamical Systems · Mathematics 2022-02-23 David Kerr , Hanfeng Li

In this work, we introduce the type and typeset invariants for equicontinuous group actions on Cantor sets; that is, for generalized odometers. These invariants are collections of equivalence classes of asymptotic Steinitz numbers…

Dynamical Systems · Mathematics 2024-10-17 Steven Hurder , Olga Lukina

Let $G$~be a real Lie group and let $G^\circ$ be the identity component of~$G$. Let $G$~act on a $C^\infty$ real manifold~$M$. Assume the action is $C^\infty$. Assume that the fixpoint set of any nontrivial element of~$G^\circ$ has empty…

Dynamical Systems · Mathematics 2017-05-26 Scot Adams

We study the uniformly recurrent subgroups of groups acting by homeomorphisms on a topological space. We prove a general result relating uniformly recurrent subgroups to rigid stabilizers of the action, and deduce a $C^*$-simplicity…

Group Theory · Mathematics 2016-12-26 Adrien Le Boudec , Nicolás Matte Bon