English
Related papers

Related papers: Partial C*-dynamics and Rokhlin dimension

200 papers

We establish rigidity for partial transformation groupoids associated with algebraic actions of semigroups: If two such groupoids (satisfying appropriate conditions) are isomorphic, then the globalizations of the initial algebraic actions…

Dynamical Systems · Mathematics 2026-04-14 Chris Bruce , Xin Li

We show that under some natural ergodicity assumptions extensions given by Rokhlin cocycles lift the multiplier property if the associated locally compact group extension has only countably many L^\infty-eigenvalues. We make use of some…

Dynamical Systems · Mathematics 2009-09-23 Tim Austin , Mariusz Lemanczyk

In 1990, Rieffel defined a notion of proper action of a group $H$ on a $C^*$-algebra $A$. He then defined a generalized fixed point algebra $A^{\alpha}$ for this action and showed that $A^{\alpha}$ is Morita equivalent to an ideal of the…

Operator Algebras · Mathematics 2009-08-03 Jonathan Henry Brown

We describe a weak tracial analog of approximate representability under the name "weak tracial approximate representability" for finite group actions. Let $G$ be a finite abelian group, let $A$ be an infinite-dimensional simple unital…

Operator Algebras · Mathematics 2023-09-20 M. Ali Asadi-Vasfi

Let $G$ be a locally compact abelian group. By modifying a theorem of Pedersen, it follows that actions of $G$ on $C^*$-algebras $A$ and $B$ are outer conjugate if and only if there is an isomorphism of the crossed products that is…

Operator Algebras · Mathematics 2018-01-03 S. Kaliszewski , Tron Omland , John Quigg

Let $A$ be an additively cancellative semialgebra over an additively cancellative semifield $K$ as defined in [9]. For a given partial action $\alpha$ of a group $G$ on an algebra, the associativity of partial skew group ring together with…

Rings and Algebras · Mathematics 2023-06-26 Thakur Meenakshi , R. P. Sharma

We construct explicit approximating nets for crossed products of C*-algebras by actions of discrete quantum groups. This implies that C*-algebraic approximation properties such as nuclearity, exactness or completely bounded approximation…

Operator Algebras · Mathematics 2014-02-26 Adam Skalski , Joachim Zacharias

We introduce dynamic asymptotic dimension, a notion of dimension for actions of discrete groups on locally compact spaces, and more generally for locally compact \'etale groupoids. We study our notion for minimal actions of the integer…

Dynamical Systems · Mathematics 2015-10-28 Erik Guentner , Rufus Willett , Guoliang Yu

For any countable discrete group $G$ with a reduced abelian subgroup of finite index, we construct an action $\alpha$ of $G$ on the universal UHF algebra $\Qq$ using an infinite tensor product of permutation representations of $G$ and show…

Operator Algebras · Mathematics 2014-09-26 Michael Sun

Suppose a locally compact group G acts freely and properly on a locally compact Hausdorff space X, and let gamma be the induced action on C_0(X). We consider a category in which the objects are C*-dynamical systems (A, G, alpha) for which…

Operator Algebras · Mathematics 2008-04-15 S. Kaliszewski , John Quigg , Iain Raeburn

In this paper we will introduce the tracial Rokhlin property for an inclusion of separable simple unital C*-algebras $P \subset A$ with finite index in the sense of Watatani, and prove theorems of the following type. Suppose that $A$…

Operator Algebras · Mathematics 2014-05-01 Hiroyuki Osaka , Tamotsu Teruya

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 show that any free action of a connected Lie group of polynomial growth on a finite dimensional locally compact space has finite tube dimension. This is shown to imply that the associated crossed product C*-algebra has finite nuclear…

Operator Algebras · Mathematics 2023-07-28 Ulrik Enstad , Gabriel Favre , Sven Raum

We extend Matui's notion of almost finiteness to general etale groupoids and show that the reduced groupoid C*-algebras of minimal almost finite groupoids have stable rank one. The proof follows a new strategy, which can be regarded as a…

Operator Algebras · Mathematics 2020-11-10 Yuhei Suzuki

In this paper we work with unital twisted partial actions. We investigate ring theoretic properties of partial crossed products as artinianity, noetherianity, perfect property, semilocalproperty, semiprimary property and we also study the…

Rings and Algebras · Mathematics 2016-03-29 Laerte Bemm , Wagner Cortes

Using a local perspective, we introduce \textit{mean dimension pairs} and give sufficient conditions of when every non-trivial factor of a continuous group action of a sofic group $G$ has positive mean dimension. In addition we show that…

Dynamical Systems · Mathematics 2024-09-18 Felipe García-Ramos , Yonatan Gutman

We consider a fixed free and proper action of a locally compact group $G$ on a space $T$, and actions $\alpha:G\to \Aut A$ on $C^*$-algebras for which there is an equivariant embedding of $(C_0(T),\rt)$ in $(M(A),\alpha)$. A recent theorem…

Operator Algebras · Mathematics 2009-07-06 Astrid an Huef , S. Kaliszewski , Iain Raeburn , Dana P. Williams

Let $\Omega$ be a class of unital ${\rm C^*}$-algebras which have the second type tracial nuclear dimensional at moat $n$ (or have tracial nuclear dimensional at most $n$). Let $A$ be an infinite dimensional unital simple ${\rm…

Operator Algebras · Mathematics 2023-05-09 Qingzhai Fan , Jiahui Wang

By previous work of Giordano and the author, ergodic actions of $\Z$ (and other discrete groups) are completely classified measure-theoretically by their dimension space, a construction analogous to the dimension group used in C*-algebras…

Dynamical Systems · Mathematics 2019-08-15 David Handelman

In this work, we introduce the notion of a partial action of a group on a strict monoidal category. We propose, in the context of Monoidal categories, new constructions analogous to those existing for partial group actions over an algebra…

Category Theory · Mathematics 2024-12-18 Eliezer Batista , Felipe Lopes Castro , Mykola Khrypchenko