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Related papers: Weak amenability for dynamical systems

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We study an ergodic theorem for disjoint C*-dynamical systems, where disjointness here is a noncommutative version of the concept introduced by Furstenberg for classical dynamical systems. This is applied to W*-dynamical systems. We also…

Operator Algebras · Mathematics 2018-06-29 Rocco Duvenhage , Anton Stroh

We prove several results on the permanence of weak amenability and the Haagerup property for discrete quantum groups. In particular, we improve known facts on free products by allowing amalgamation over a finite quantum subgroup. We also…

Operator Algebras · Mathematics 2014-11-18 Amaury Freslon

This note establishes a new weak mean ergodic theorem for 1-cocycles associated to weakly mixing representations of amenable groups.

Functional Analysis · Mathematics 2018-02-21 Ionut Chifan , Thomas Sinclair

We investigate approximation properties for $C^*$-algebras and their crossed products by actions and coactions by locally compact groups. We show that Haagerup's approximation constant is preserved for crossed products by arbitrary amenable…

Operator Algebras · Mathematics 2007-05-23 May Nilsen , Roger Smith

In the first part of the paper we describe the dual \ell^2(A)^{\prime} of the standard Hilbert C*-module \ell^2(A) over an arbitrary (not necessarily unital) C*-algebra A. When A is a von Neumann algebra, this enables us to construct…

Operator Algebras · Mathematics 2019-12-19 Damir Bakic

We give a new formulation of some of our recent results on the following problem: if all uniformly bounded representations on a discrete group $G$ are similar to unitary ones, is the group amenable? In \S 5, we give a new proof of…

Operator Algebras · Mathematics 2007-05-23 Gilles Pisier

We study a nonconventional ergodic average for asymptotically abelian weakly mixing C*-dynamical systems, related to a second iteration of Khintchine's recurrence theorem obtained by Bergelson in the measure theoretic case. A noncommutative…

Operator Algebras · Mathematics 2009-06-22 Rocco Duvenhage

We study non-recurrence sets for weakly mixing dynamical systems by using linear dynamical systems. These are systems consisting of a bounded linear operator acting on a separable complex Banach space X, which becomes a probability space…

Dynamical Systems · Mathematics 2019-02-20 Sophie Grivaux

The Drinfeld double associated to the weak multiplier Hopf ($*$-) algebra pairing $\left\langle A, B\right\rangle$ is constructed. We show that the Drinfeld double is again a weak multiplier Hopf ($*$-) algebra. If $A$ and $B$ are algebraic…

Quantum Algebra · Mathematics 2023-06-26 Nan Zhou , Shuanhong Wang

Let $(A,G,\alpha)$ be a partial dynamical system and let $A\rtimes_{\alpha,r} G$ denote the associated reduced partial crossed product. In this article, we introduce the Haagerup property for partial actions of discrete groups on…

Operator Algebras · Mathematics 2026-04-07 Md Amir Hossain , Chaitanya J. Kulkarni

We prove a version of the Cuntz--Krieger Uniqueness Theorem for $C^*$-algebras of arbitrary relative generalized Boolean dynamical systems. We then describe properties of a $C^*$-algebra of a relative generalized Boolean dynamical system…

Operator Algebras · Mathematics 2023-05-17 Toke Meier Carlsen , Eun Ji Kang

In this work we introduce and study a new notion of amenability for actions of locally compact groups on $C^*$-algebras. Our definition extends the definition of amenability for actions of discrete groups due to Claire…

Operator Algebras · Mathematics 2022-05-04 Alcides Buss , Siegfried Echterhoff , Rufus Willett

A collection of partial isometries whose range and initial projections satisfy a specified set of conditions often gives rise to a partial representation of a group. The C*-algebra generated by the partial isometries is thus a quotient of…

funct-an · Mathematics 2016-08-31 Ruy Exel , Marcelo Laca , John Quigg

The weak Haagerup property for locally compact groups and the weak Haagerup constant was recently introduced by the second author. The weak Haagerup property is weaker than both weak amenability introduced by Cowling and the first author…

Operator Algebras · Mathematics 2016-09-19 Uffe Haagerup , Søren Knudby

We study variants of the Dixmier property that apply to elements of a unital C*-algebra, rather than to the C*-algebra itself. By a Dixmier element in a C*-algebra we understand one that can be averaged into a central element by means of a…

Operator Algebras · Mathematics 2021-06-02 Robert J. Archbold , Ilja Gogić , Leonel Robert

Let $G$ be a locally compact group, and let $A_\cb(G)$ denote the closure of $A(G)$, the Fourier algebra of $G$, in the space of completely bounded multipliers of $A(G)$. If $G$ is a weakly amenable, discrete group such that $\cstar(G)$ is…

Functional Analysis · Mathematics 2007-10-12 Brian E. Forrest , Volker Runde , Nico Spronk

In this paper, we study the weak amenability of weighted measure algebras and prove that $M(G, \omega)$ is weakly amenable if and only if $G$ is discrete and every bounded quasi-additive function is inner. We also study the weak amenability…

Functional Analysis · Mathematics 2022-10-11 M. J. Mehdipour , A. Rejali

We shall develop a notion of amenability for dual Banach algebras, namely weak Connes amenability, which will play the role that weak amenability does for usual Banach algebras

Functional Analysis · Mathematics 2021-09-02 Amin Mahmoodi

A locally compact group $G$ is said to be weakly amenable if the Fourier algebra $A(G)$ admits completely bounded approximative units. Consider the family of groups $G_n=SL(2,\Bbb R)\ltimes H_n$ where $n\ge 2$, $H_n$ is the $2n+1$…

Functional Analysis · Mathematics 2010-03-15 Michael Cowling , Brian Dorofaeff , Andreas Seeger , James Wright

We study actions of discrete groups on Hilbert $C^*$-modules induced from topological actions on compact Hausdorff spaces. We show non-amenability of actions of non-amenable and non-a-T-menable groups, provided there exists a…

Functional Analysis · Mathematics 2011-08-09 Ronald G. Douglas , Piotr W. Nowak