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Related papers: Amenability via random walks

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We introduce two natural notions of cogrowth for finitely generated semigroups --- one local and one global --- and study their relationship with amenability and random walks. We establish the minimal and maximal possible values for…

Group Theory · Mathematics 2017-06-06 Robert D. Gray , Mark Kambites

This survey is concerned with random walks on mapping class groups. We illustrate how the actions of mapping class groups on Teichm\"uller spaces or curve complexes reveal the nature of random walks, and vice versa. Our emphasis is on the…

Geometric Topology · Mathematics 2021-10-12 Inhyeok Choi , Hyungryul Baik

We use $\mathrm{C}^{\ast}$-algebra ultrapowers to give a new construction of the Stone-Cech compactification of a separable, locally compact space. We use this construction to give a new proof of the fact that groups that act isometrically,…

Group Theory · Mathematics 2016-10-31 Stephen Avsec , Isaac Goldbring

In this short note we study the entropy for algebraic actions of certain amenable groups. The possible values for this entropy are studied. Various fundamental results about certain classes of amenable groups are reproved using elementary…

Dynamical Systems · Mathematics 2013-03-15 Nhan-Phu Chung , Andreas Thom

We generalize the notion of isoperimetric profiles of finitely generated groups to their actions by measuring the boundary of finite subgraphings of the orbit graphing. We prove that like the classical isoperimetric profiles for groups,…

Dynamical Systems · Mathematics 2023-10-05 Zihan Xia

We extend some properties of random walks on hyperbolic groups to random walks on convergence groups. In particular we prove that if a convergence group $G$ acts on a compact metrizable space $M$ with the convergence property then we can…

Geometric Topology · Mathematics 2020-06-16 Aitor Azemar

Generalizing Block and Weinberger's characterization of amenability we introduce the notion of uniformly finite homology for a group action on a compact space and use it to give a homological characterization of topological amenability for…

Group Theory · Mathematics 2010-12-14 Jacek Brodzki , Graham A. Niblo , Piotr Nowak , Nick J. Wright

We consider random walks on countable groups. A celebrated result of Kesten says that the spectral radius of a symmetric walk (whose support generates the group as a semigroup) is equal to one if and only if the group is amenable. We give…

Group Theory · Mathematics 2023-09-06 Rhiannon Dougall , Richard Sharp

Symbolic dynamical theory plays an important role in the research of amenability with a countable group. Motivated by the deep results of Dougall and Sharp, we study the group extensions for topologically mixing random shifts of finite…

Dynamical Systems · Mathematics 2024-03-21 Kexiang Yang , Ercai Chen , Zijie Lin , Xiaoyao Zhou

We are interested in the Guivarc'h inequality for admissible random walks on finitely generated relatively hyperbolic groups, endowed with a word metric. We show that for random walks with finite super-exponential moment, if this inequality…

Group Theory · Mathematics 2019-08-06 Matthieu Dussaule , Ilya Gekhtman

Initial steps are presented towards understanding which finitely generated groups are almost surely generated as semigroups by the path of a random walk on the group.

Group Theory · Mathematics 2012-12-27 Itai Benjamini , Hilary Finucane , Romain Tessera

We show that a free action $G \curvearrowright X$ is almost finite if its restriction to some infinite normal subgroup of $G$ is almost finite. Consider the class of groups which contains all infinite groups of locally subexponential growth…

Dynamical Systems · Mathematics 2023-06-01 Petr Naryshkin

In this paper we study analogues of amenability for topological groups in the context of definable structures. We prove fixed point theorems for such groups. More importantly, we propose definitions for definable actions and continuous…

Logic · Mathematics 2018-12-14 Alf Onshuus , Luis Carlos Suárez

People tend to walk in groups, and interactions with those groups have a significant impact on crowd behavior and pedestrian traffic dynamics. Social norms can be seen as unwritten rules regulating people interactions in social settings.…

Physics and Society · Physics 2025-10-31 Saleh Albeaik , Faisal Alsallum , Mohamad Alrished

We define a notion of relative soficity for countable groups with respect to a family of groups. A group is sofic if and only if it is relative sofic with respect to the family consisting only of the trivial group. If a group is relatively…

Group Theory · Mathematics 2019-01-11 Ronghui Ji , Crichton Ogle , Bobby Ramsey

Amenable category is a variant of the Lusternik-Schnirelman category, based on covers by amenable open subsets. We study the monotonicity problem for degree-one maps and amenable category and the relation between amenable category and…

Algebraic Topology · Mathematics 2022-09-07 Pietro Capovilla , Clara Loeh , Marco Moraschini

We study the automorphism groups of countable homogeneous directed graphs (and some additional homogeneous structures) from the point of view of topological dynamics. We determine precisely which of these automorphism groups are amenable…

Combinatorics · Mathematics 2017-12-29 Micheal Pawliuk , Miodrag Sokic

We consider an action of a countable amenable group on a compact metric space, focusing on the set of generic points with respect to a fixed F{\o}lner sequence. For a given characteristic class, we prove that the set of points that are…

Dynamical Systems · Mathematics 2025-10-31 Sejal Babel , Martha Łącka , Marcel Mroczek

We show that topological amenability of an action of a countable discrete group on a compact space is equivalent to the existence of an invariant mean for the action. We prove also that this is equivalent to vanishing of bounded cohomology…

Group Theory · Mathematics 2010-04-05 Jacek Brodzki , Graham A. Niblo , Piotr Nowak , Nick Wright

We completely characterize connected Lie groups all of whose countable subgroups are weakly amenable. We also provide a characterization of connected semisimple Lie groups that are weakly amenable. Finally, we show that a connected Lie…

Functional Analysis · Mathematics 2018-10-17 Søren Knudby