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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

We show that for any countable discrete maximally almost periodic group $G$ and any UHF algebra $A$, there exists a strongly outer product type action $\alpha$ of $G$ on $A$. We also show the existence of countable discrete almost abelian…

Operator Algebras · Mathematics 2014-09-02 Michael Y. Sun

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

We introduce the tracial Rokhlin property for automorphisms of stably finite simple unital C*-algebras containing enough projections. This property is formally weaker than the various Rokhlin properties considered by Herman and Ocneanu,…

Operator Algebras · Mathematics 2007-05-23 Hiroyuki Osaka , N. Christopher Phillips

Let G be a finite group, let A be an infinite-dimensional stably finite simple unital C*-algebra, and let \alpha \colon G \to Aut (A) be an action of G on A which has the weak tracial Rokhlin property. Let A^{\alpha} be the fixed point…

Operator Algebras · Mathematics 2019-08-20 M. Ali Asadi-Vasfi , Nasser Golestani , N. Christopher Phillips

We develop the notion of Rokhlin dimension for partial actions of finite groups, extending the well-established theory for global systems. The partial setting exhibits phenomena that cannot be expected for global actions, usually stemming…

Operator Algebras · Mathematics 2022-01-25 Fernando Abadie , Eusebio Gardella , Shirly Geffen

We establish four results concerning connections between actions on separable C*-algebras with Rokhlin-type properties and absorption of the Jiang-Su algebra Z. For actions of residually finite groups or of the reals which have finite…

Operator Algebras · Mathematics 2020-07-07 Ilan Hirshberg

Tracial Rokhlin property was introduced by Phillips to prove various structure theorems for crossed product. But it is defined for actions on simple C*-algebras only. This paper consists of two major parts: In section 2 and 3, we study the…

Operator Algebras · Mathematics 2012-11-26 Qingyun Wang

We establish comparison and divisibility properties for crossed product C*-algebras arising from automorphisms of algebras C (X, D) which lie over minimal homeomorphisms, from actions of compact groups which have finite Rokhlin dimension…

Operator Algebras · Mathematics 2026-04-14 Dawn Archey , Julian Buck , Javad Mohammadkarimi , N. Christopher Phillips , Apurva Seth

In this article, we consider a twisted partial action $\alpha$ of a group $G$ on a ring $R$ and it is associated partial crossed product $R*_{\alpha}^wG$. We study necessary and sufficient conditions for the commutativity and simplicity of…

Rings and Algebras · Mathematics 2013-06-25 Alexandre Baraviera , Wagner Cortes , Marlon Soares

In this paper, we show that one of the conditions in the definition of weak tracial Rokhlin property for finite group actions on simple unital C*-algebras can be replaced by a seemingly weaker condition, or a seemingly stronger condition.…

Operator Algebras · Mathematics 2023-05-31 Xiaochun Fang , Zhongli Wang

We prove several results of the following general form: automorphisms of (or actions of ${\mathbb{Z}}^d$ on) certain kinds of simple separable unital C*-algebras $A$ which have a suitable version of the Rokhlin property are generic among…

Operator Algebras · Mathematics 2012-09-19 N. Christopher Phillips

We give examples of actions of Z/2Z on AF algebras and AT algebras which demonstrate the differences between the (strict) Rokhlin property and the tracial Rokhlin property, and between (strict) approximate representability and tracial…

Operator Algebras · Mathematics 2007-05-23 N. Christopher Phillips

We introduce the notion of the weak tracial approximate representability of a discrete group action on a unital $C^*$-algebra which could have no projections like the Jiang-Su algebra $\mathcal{Z}$. Then we show a duality between the weak…

Operator Algebras · Mathematics 2022-08-30 Hyun Ho Lee

For a finite symmetry group $G$ of an aperiodic substitution tiling system $(\p,\omega)$, we show that the crossed product of the tiling C*-algebra $\Aw$ by $G$ has real rank zero, tracial rank one, a unique trace, and that order on its…

Operator Algebras · Mathematics 2013-08-14 Charles Starling

We provide a systematic and in-depth study of compact group actions with the Rokhlin property. It is show that the Rokhlin property is generic in some cases of interest; the case of totally disconnected groups being the most satisfactory…

Operator Algebras · Mathematics 2018-02-06 Eusebio Gardella

In a previous paper, we introduced the restricted tracial Rokhlin property with comparison, a ``tracial'' analog of the Rokhlin property for actions of second countable compact groups on infinite dimensional simple separable unital…

Operator Algebras · Mathematics 2025-05-09 Javad Mohammadkarimi , N. Christopher Phillips

For an action of a finite group on a C*-algebra, we present some conditions under which properties of the C*-algebra pass to the crossed product or the fixed point algebra. We mostly consider the ideal property, the projection property,…

Operator Algebras · Mathematics 2012-08-21 Cornel Pasnicu , N. Christopher Phillips

Let $G$ be a metrizable compact group, $A$ a separable C*-algebra and $\alpha$ a strongly continuous action of $G$ on $A$. Provided that $\alpha$ satisfies the continuous Rokhlin property, we show that the property of satisfying the UCT in…

Operator Algebras · Mathematics 2015-12-22 Gabor Szabo

We introduce a general class of automorphisms of rotation algebras, the noncommutative Furstenberg transformations. We prove that fully irrational noncommutative Furstenberg transformations have the tracial Rokhlin property, which is a…

Operator Algebras · Mathematics 2007-05-23 Hiroyuki Osaka , N. Christopher Phillips