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Related papers: On relative extreme amenability

200 papers

P-E. Caprace and N. Monod isolate the class $\mathscr{X}$ of locally compact groups for which relatively amenable closed subgroups are amenable. It is unknown if $\mathscr{X}$ is closed under group extension. In this note, we exhibit a…

Group Theory · Mathematics 2016-03-07 Phillip Wesolek

A (discrete) group is called amenable whenever there exists a finitely additive right invariant probablity measure on it. For Thompson's group $F$ the problem whether it is amenable is a long-standing open question. We consider presentation…

Group Theory · Mathematics 2023-04-11 Victor Guba

The goal of this article is to study results and examples concerning finitely presented covers of finitely generated amenable groups. We collect examples of groups $G$ with the following properties: (i) $G$ is finitely generated, (ii) $G$…

Group Theory · Mathematics 2013-05-06 Mustafa Gokhan Benli , Rostislav Grigorchuk , Pierre De La Harpe

In this paper, we have studied 'absorbing' and 'balanced' sets in an Exponential Vector Space (\emph{evs} in short) over the field $\mathbb K$ of real or complex. These sets play pivotal role to describe several aspects of a topological…

Functional Analysis · Mathematics 2020-06-08 Priti Sharma , Sandip Jana

A group is said to be strongly amenable if each of its proximal topological actions has a fixed point. We show that a finitely generated group is strongly amenable if and only if it is virtually nilpotent. More generally, a countable…

Group Theory · Mathematics 2020-01-08 Joshua Frisch , Omer Tamuz , Pooya Vahidi Ferdowsi

We introduce a new combinatorial condition that characterises the amenability for locally compact groups. Our condition is weaker than the well-known F{\o}lner's conditions, and so is potentially useful as a criteria to show the amenability…

Functional Analysis · Mathematics 2023-10-31 Hung Pham

We give a new perspective on the homological characterisations of amenability given by Johnson in the context of bounded cohomology and by Block and Weinberger in the context of uniformly finite homology. We examine the interaction between…

Group Theory · Mathematics 2010-03-15 Jacek Brodzki , Graham A. Niblo , Nick Wright

We formulate and prove a very general relative version of the Dobrushin-Lanford-Ruelle theorem which gives conditions on constraints of configuration spaces over a finite alphabet such that for every absolutely summable relative…

Mathematical Physics · Physics 2020-05-07 Sebastián Barbieri , Ricardo Gómez , Brian Marcus , Siamak Taati

We extend the Kechris--Pestov--Todor\v{c}evi\'c correspondence to weak Fra\"{\i}ss\'{e} categories and automorphism groups of generic objects. The new ingredient is the weak Ramsey property. We demonstrate the theory on several examples…

Logic · Mathematics 2024-11-20 Adam Bartoš , Tristan Bice , Keegan Dasilva Barbosa , Wiesław Kubiś

This paper aims to investigate the thermodynamic formalism of weighted amenable topological pressure for factor maps of amenable group actions. Following the approach of Tsukamoto [\emph{Ergodic Theory Dynam. Syst.} \textbf{43}(2023),…

Dynamical Systems · Mathematics 2023-07-10 Jiao Yang , Ercai Chen , Rui Yang , Xiaoyi Yang

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 study properties related to nice enumerability of countably categorical structures and properties related to extreme amenability of automorphism groups of these structures. The text substantially differs from the previous version. In…

Logic · Mathematics 2014-10-24 Aleksander Ivanov

In this paper, we show that there is a net for amenable transformation groups like F{\o}lner net for amenable groups and investigate amenability of a transformation group constructed by semidirect product of groups. We introduce inner…

Functional Analysis · Mathematics 2026-04-10 Ali Ebadian , Ali Jabbari

In this paper, we first prove the variational principle for amenable packing topological pressure. Then we obtain an inequality concerning amenable packing pressure for factor maps. Finally, we show that the equality about packing…

Dynamical Systems · Mathematics 2024-05-27 Ziqing Ding , Ercai Chen , Xiaoyao Zhou

We analyze the dichotomy amenable/paradoxical in the context of (discrete, countable, unital) semigroups and corresponding semigroup rings. We consider also F{\o}lner's type characterizations of amenability and give an example of a…

Operator Algebras · Mathematics 2022-07-11 Pere Ara , Fernando Lledó , Diego Martínez

A new flavour of amenability for discrete semigroups is proposed that generalises group amenability and follows from a \Folner-type condition. Some examples are explored, to argue that this new notion better captures some essential ideas of…

Group Theory · Mathematics 2016-04-27 Josh Deprez

In this article, we introduce and explore the notion of topological amenability in the broad setting of (locally compact) semihypergroups. We acquire several stationary, ergodic and Banach algebraic characterizations of the same in terms of…

Functional Analysis · Mathematics 2023-11-29 Choiti Bandyopadhyay

We define regular points of an extremal subset in an Alexandrov space and study their basic properties. We show that a neighborhood of a regular point in an extremal subset is almost isometric to an open subset in Euclidean space and that…

Differential Geometry · Mathematics 2023-01-18 Tadashi Fujioka

We give a complete characterization of the locally compact groups that are non-elementary Gromov-hyperbolic and amenable. They coincide with the class of mapping tori of discrete or continuous one-parameter groups of compacting…

Group Theory · Mathematics 2015-10-29 Pierre-Emmanuel Caprace , Yves de Cornulier , Nicolas Monod , Romain Tessera

We investigate the theory of finite observables, i.e., resolutions of the finite-dimensional identity by means of positive operators, that have a physical interpretation in terms of measurement schemes. We focus on extremal and rank-one…

Quantum Physics · Physics 2019-07-01 Heinz-Jürgen Schmidt