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Related papers: Skew-amenability of topological groups

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Skew morphisms, which generalise automorphisms for groups, provide a fundamental tool for the study of regular Cayley maps and, more generally, for finite groups with a complementary factorisation $G=BY$, where $Y$ is cyclic and core-free…

Combinatorics · Mathematics 2019-05-03 Martin Bachratý , Marston Conder , Gabriel Verret

Sofic groups generalise both residually finite and amenable groups, and the concept is central to many important results and conjectures in measured group theory. We introduce a topological notion of a sofic boundary attached to a given…

Group Theory · Mathematics 2026-04-28 Vadim Alekseev , Martin Finn-Sell

We study automorphism groups of sparse graphs from the viewpoint of topological dynamics and the Kechris, Pestov, Todor\v{c}evi\'c correspondence. We investigate amenable and extremely amenable subgroups of these groups using the space of…

Group Theory · Mathematics 2019-03-13 David M. Evans , Jan Hubička , Jaroslav Nešetřil

We study groups acting by length-preserving transformations on spaces equipped with asymmetric, partially-defined distance functions. We introduce a natural notion of quasi-isometry for such spaces and exhibit an extension of the…

Group Theory · Mathematics 2009-06-03 Robert Gray , Mark Kambites

We discuss relations between the amenability of a graph and spectral properties of a random walk driven by a dynamical system. In order to include graphs which are not locally compact, we introduce the concept of amenability of weighted…

Dynamical Systems · Mathematics 2024-04-15 Johannes Jaerisch , Elaine Rocha , Manuel Stadlbauer

We investigate recent uniqueness theorems for reduced $C^*$-algebras of Hausdorff \'{e}tale groupoids in the context of inverse semigroups. In many cases the distinguished subalgebra is closely related to the structure of the inverse…

Operator Algebras · Mathematics 2016-11-11 Scott M. LaLonde , David Milan

In this note we extend the concept of topological stability from homeomorphisms to group actions on compact metric spaces, and prove that if an action of a finitely generated group is expansive and has the pseudo-orbit tracing property then…

Dynamical Systems · Mathematics 2016-11-29 Nhan-Phu Chung , Keonhee Lee

A natural topology on the space of left orderings of an arbitrary semi-group is introduced. It is proved that this space is compact and that for free abelian groups it is homeomorphic to the Cantor set. An application of this result is a…

Group Theory · Mathematics 2015-05-27 Adam S. Sikora

We show that every amenable group with a locally invariant partial order has a left-invariant total order (and is therefore locally indicable). We also show that if a group G admits a left-invariant total order, and H is a locally nilpotent…

Group Theory · Mathematics 2013-04-11 Peter Linnell , Dave Witte Morris

We show how all topological full groups coming from a one-sided irreducible shift of finite type, as studied by Matui, can be re-interpreted as groups of colour-preserving tree almost automorphisms. As an application, we show that they…

Group Theory · Mathematics 2018-06-05 Waltraud Lederle

We initiate the study of a measurable analogue of small topological full groups that we call $\mathrm L^1$ full groups. These groups are endowed with a Polish group topology which admits a natural complete right invariant metric. We mostly…

Dynamical Systems · Mathematics 2018-05-08 François Le Maître

We prove that amenability of a discrete group is equivalent to dimension flatness of certain ring inclusions naturally associated with measure preserving actions of the group. This provides a group-measure space theoretic solution to a…

Group Theory · Mathematics 2013-05-16 David Kyed , Henrik Densing Petersen

We point out a simple characterisation of topological amenability in terms of bounded cohomology, following Johnson's reformulation of amenability.

Group Theory · Mathematics 2012-07-10 Nicolas Monod

Let $F$ denote the Thompson group with standard generators $A=x_0$, $B=x_1$. It is a long standing open problem whether $F$ is an amenable group. By a result of Kesten from 1959, amenability of $F$ is equivalent to $$(i)\qquad ||I+A+B||=3$$…

Group Theory · Mathematics 2015-02-09 S. Haagerup , U. Haagerup , M. Ramirez-Solano

We show that if $G$ is an amenable group and $A\subseteq G$ has positive upper Banach density, then there is an identity neighborhood $B$ in the Bohr topology on $G$ that is almost contained in $AA^{-1}$ in the sense that $B\backslash…

Dynamical Systems · Mathematics 2025-06-18 Gabriel Conant

The relation between manifold topology, observables and gauge group is clarified on the basis of the classification of the representations of the algebra of observables associated to positions and displacements on the manifold. The guiding,…

Quantum Physics · Physics 2021-12-01 G. Morchio , F. Strocchi

Packing topological entropy is a dynamical analogy of the packing dimension, which can be viewed as a counterpart of Bowen topological entropy. In the present paper, we will give a systematically study to the packing topological entropy for…

Dynamical Systems · Mathematics 2021-09-29 Dou Dou , Dongmei Zheng , Xiaomin Zhou

Let $(X, \sigma)$ be a transitive sofic shift and let $\rm{Aut}(X)$ denote its automorphism group. We generalize a result of Frisch, Schlank, and Tamuz to show that any normal amenable subgroup of $\rm{Aut}(X)$ must be contained in the…

Dynamical Systems · Mathematics 2021-07-01 Kitty Yang

We introduce a notion of a topologically flat locally convex module, which extends the notion of a flat Banach module and which is well adapted to the nonmetrizable setting (and especially to the setting of DF-modules). By using this…

Functional Analysis · Mathematics 2020-12-17 Alexei Yu. Pirkovskii , Krzysztof Piszczek

Stackability for finitely presented groups consists of a dynamical system that iteratively moves paths into a maximal tree in the Cayley graph. Combining with formal language theoretic restrictions yields auto- or algorithmic stackability,…

Group Theory · Mathematics 2016-05-23 Susan Hermiller , Conchita Martínez-Pérez