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Related papers: Amenability and the bicrossed product construction

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We undertake a comprehensive study of measure equivalence between general locally compact, second countable groups, providing operator algebraic and ergodic theoretic reformulations, and complete the classification of amenable groups within…

Group Theory · Mathematics 2021-01-13 Juhani Koivisto , David Kyed , Sven Raum

In this paper, we deal with cohomological properties of weak amenability, cyclic amenability, cyclic weak amenability and point amenability of Banach algebras. We look at some hereditary properties of them and show that continuous…

Functional Analysis · Mathematics 2022-10-10 M. J. Mehdipour , A. Rejali

We prove that every uniform approximate homomorphism from a discrete amenable group into a symmetric group is uniformly close to a homomorphism into a slightly larger symmetric group. That is, amenable groups are uniformly flexibly stable…

Group Theory · Mathematics 2020-05-15 Oren Becker , Michael Chapman

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

We study when certain properties of Banach algebras are stable under ultrapower constructions. In particular, we consider when every ultrapower of $\mc A$ is Arens regular, and give some evidence that this is if and only if $\mc A$ is…

Functional Analysis · Mathematics 2010-03-16 Matthew Daws

We introduce the notion of an action of a discrete or compact quantum group on an operator system, and study equivariant operator system injectivity. We then prove a duality result that relates equivariant injectivity with dual injectivity…

Operator Algebras · Mathematics 2024-06-06 Joeri De Ro , Lucas Hataishi

Let C be a class of groups. We give sufficient conditions ensuring that a free product of residually C groups is again residually C, and analogous conditions are given for locally embeddable into C groups. As a corollary, we obtain that the…

Group Theory · Mathematics 2015-01-14 Federico Berlai

We present a general new method for constructing pointwise ergodic sequences on countable groups, which is applicable to amenable as well as to non-amenable groups and treats both cases on an equal footing. The principle underlying the…

Dynamical Systems · Mathematics 2013-03-20 Lewis Bowen , Amos Nevo

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 prove that the amalgamated free product of two free groups of rank two over a common cyclic subgroup, admits an amenable, faithful, transitive action on an infinite countable set. We also show that any finite index subgroup admits such…

Group Theory · Mathematics 2010-03-23 Soyoung Moon

The objective of this series is to study metric geometric properties of (coarse) disjoint unions of amenable Cayley graphs. We employ the Cayley topology and observe connections between large scale structure of metric spaces and group…

Group Theory · Mathematics 2019-03-13 Masato Mimura , Hiroki Sako

We study the Haagerup--Kraus approximation property for locally compact quantum groups, generalising and unifying previous work by Kraus--Ruan and Crann. Along the way we discuss how multipliers of quantum groups interact with the…

Operator Algebras · Mathematics 2024-01-05 Matthew Daws , Jacek Krajczok , Christian Voigt

We introduce the construction of induced corepresentations in the setting of locally compact quantum groups and prove that the resulting induced corepresentations are unitary under some mild integrability condition. We also establish a…

Operator Algebras · Mathematics 2007-05-23 Johan Kustermans

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

Let A be a Banach algebra and I be a closed ideal of A. We say that A is amenable relative to I, if A/I is an amenable Banach algebra. We study the relative amenability of Banach algebras and investigate the relative amenability of…

Functional Analysis · Mathematics 2019-12-02 Hoger Ghahramani , Wania Khodakarami , Esmaeil Feizi

We determine when a quasi-isometry between discrete spaces is at bounded distance from a bilipschitz map. From this we prove a geometric version of the Von Neumann conjecture on amenability. We also get some examples in geometric groups…

Group Theory · Mathematics 2009-09-25 Kevin Whyte

We study universal groups for right-angled buildings. Inspired by Simon Smith's work on universal groups for trees, we explicitly allow local groups that are not necessarily finite nor transitive. We discuss various topological and…

Group Theory · Mathematics 2021-01-28 Jens Bossaert , Tom De Medts

For two Banach algebras $A$ and $B$, the $T$-Lau product $A\times_T B$, was recently introduced and studied for some bounded homomorphism $T:B\to A$ with $\|T\|\leq 1$. Here, we give general nessesary and sufficent conditions for $A\times_T…

Functional Analysis · Mathematics 2017-01-24 Mohammad Ramezanpour

We initiate an investigation into the local structure of simple nonnuclear C$^*$-crossed products by showing that stable rank one is generic within two natural classes of minimal actions of free groups on the Cantor set. The arguments also…

Operator Algebras · Mathematics 2025-11-26 Jamie Bell , Shirly Geffen , David Kerr

The equivariant cohomology for actions of compact connected abelian groups and elementary abelian p-groups have been widely studied in the last decades. We study some of these results on actions of finite cyclic groups over a field of…

Algebraic Topology · Mathematics 2022-06-24 Sergio Chaves