Amenability, exactness and weak containment property for groupoids

C Anantharaman-Delaroche - arXiv preprint arXiv:2306.17613, 2023 - arxiv.org
From the mid-1970s, Eberhard Kirchberg undertook a remarkable extensive study of $ C^* $-
algebras exactness whose applications spread out to many branches of analysis. In this …

The dynamical Kirchberg-Phillips theorem

J Gabe, G Szabó - arXiv preprint arXiv:2205.04933, 2022 - arxiv.org
Let $ G $ be a second-countable, locally compact group. In this article we study amenable $
G $-actions on Kirchberg algebras that admit an approximately central embedding of a …

Classification of equivariantly O2-stable amenable actions on nuclear C⁎-algebras

M Pagliero, G Szabó - Journal of Functional Analysis, 2025 - Elsevier
Given a second-countable, locally compact group G, we consider amenable G-actions on
separable, stable, nuclear C⁎-algebras that are isometrically shift-absorbing and tensorially …

Amenability and weak containment for actions of locally compact groups on -algebras

A Buss, S Echterhoff, R Willett - arXiv preprint arXiv:2003.03469, 2020 - arxiv.org
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 …

Tracially amenable actions and purely infinite crossed products

E Gardella, S Geffen, J Kranz, P Naryshkin… - Mathematische …, 2024 - Springer
We introduce the notion of tracial amenability for actions of discrete groups on unital, tracial
C∗-algebras, as a weakening of amenability where all the relevant approximations are done …

[HTML][HTML] Approximation properties for dynamical W⁎-correspondences

K De Commer, J De Ro - Advances in Mathematics, 2024 - Elsevier
Let G be a locally compact quantum group, and A, B von Neumann algebras on which G
acts. We refer to these as G-dynamical W⁎-algebras. We make a study of G-equivariant AB …

Approximation properties of Fell bundles over inverse semigroups and non-Hausdorff groupoids

A Buss, D Martínez - Advances in Mathematics, 2023 - Elsevier
In this paper we study the nuclearity and weak containment property of reduced cross-
sectional C⁎-algebras of Fell bundles over inverse semigroups. In order to develop the …

Exact groupoids

C Anantharaman-Delaroche - arXiv preprint arXiv:1605.05117, 2016 - arxiv.org
Our purpose is to introduce in the setting of locally compact groupoids the analogues of the
well known equivalent definitions of exactness for discrete groups. We study the relations …

Amenability and approximation properties for partial actions and Fell bundles

F Abadie, A Buss, D Ferraro - Bulletin of the Brazilian Mathematical Society …, 2022 - Springer
Building on previous papers by Anantharaman-Delaroche (AD) we introduce and study the
notion of AD-amenability for partial actions and Fell bundles over discrete groups. We prove …

Equivariant property (SI) revisited, II

G Szabó - arXiv preprint arXiv:2308.08878, 2023 - arxiv.org
We investigate Matui-Sato's notion of property (SI) for C*-dynamics, this time with a focus on
actions of possibly non-amenable groups. The main result is a generalization of earlier work …