English
Related papers

Related papers: Injective envelopes and the intersection property

200 papers

Let $\alpha: G\curvearrowright X$ be a minimal free continuous action of an infinite countable amenable group on an infinite compact metrizable space. In this paper, under the hypothesis that the invariant ergodic probability Borel measure…

Dynamical Systems · Mathematics 2018-06-29 Xin Ma

We give a number of equivalent conditions (including weak centrality) for a general $C^*$-algebra to have the centre-quotient property. We show that every $C^*$-algebra $A$ has a largest weakly central ideal $J_{wc}(A)$. For an ideal $I$ of…

Operator Algebras · Mathematics 2020-10-14 Robert J. Archbold , Ilja Gogić

We study the C*-algebra crossed-product of the closed unit disk by the action of one of its conformal automorphisms. After classifying the conformal automorphisms up to topological conjugacy, we investigate, for each class, the irreducible…

Operator Algebras · Mathematics 2011-10-10 Man-Duen Choi , Frederic Latremoliere

For Ore semigroups $P$ with an order unit, we prove that there is a bijection between $E_0$-semigroups over $P$ and product systems of $C^{*}$-correspondences over $P^{op}$. We exploit this bijection and show that the reduced…

Operator Algebras · Mathematics 2025-07-29 Md Amir Hossain , S. Sundar

We generalize Renault's notion of measurewise amenability to actions of second countable, Hausdorff, \'etale groupoids on separable $C^*$-algebras and show that measurewise amenability characterizes nuclearity of the crossed product…

Operator Algebras · Mathematics 2023-01-31 Julian Kranz

We extend applications of Furstenberg boundary theory to the study of $C^*$-algebras associated to minimal actions $\Gamma\!\curvearrowright\! X$ of discrete groups $\Gamma$ on locally compact spaces $X$. We introduce boundary maps on…

Operator Algebras · Mathematics 2022-03-03 Mehrdad Kalantar , Eduardo Scarparo

The closed one-sided ideals of a C*-algebra are exactly the closed subspaces supported by the orthogonal complement of a closed projection. Let A be a (not necessarily selfadjoint) subalgebra of a unital C*-algebra B which contains the unit…

Operator Algebras · Mathematics 2007-05-23 Damon M. Hay

In this paper we suggest a definition for a C*-algebra attached to an injective morphism of some \'Etale groupoid. We take into account all the peculiarities of such objects and present some interesting relations with already well-known…

Operator Algebras · Mathematics 2022-04-22 Bruno Tadeu Costa , Renan Gambale Romano , Felipe Vieira

We show that a normal coaction of a discrete group on an operator algebra extends to a normal coaction on the C*-envelope. This resolves an open problem attempted by several experts in the area, and provides a more direct proof of a…

Operator Algebras · Mathematics 2026-04-06 Kevin Aguyar Brix , Chris Bruce , Adam Dor-On

We show that for a locally compact group G there is a one-to-one correspondence between G-invariant weak*-closed subspaces E of the Fourier-Stieltjes algebra B(G) containing B_r(G) and quotients C*_E(G) of C*(G) which are intermediate…

Operator Algebras · Mathematics 2013-09-02 S. Kaliszewski , Magnus B. Landstad , John Quigg

We study actions of countable discrete amenable groups on unital separable simple nuclear Z-absorbing C*-algebras. Under a certain assumption on tracial states, which is automatically satisfied in the case of a unique tracial state, the…

Operator Algebras · Mathematics 2016-12-28 Yasuhiko Sato

Let $G$ be a finite group, let $A$ be an infinite-dimensional stably finite simple unital C*-algebra, and let $\alpha \colon G \to \operatorname{Aut} (A)$ be a tracially strictly approximately inner action of $G$ on $A$. Then the radius of…

Operator Algebras · Mathematics 2023-09-01 M. Ali Asadi-Vasfi

For the $C^*$-crossed product $C^*(\Sigma)$ associated with an arbitrary topological dynamical system $\Sigma = (X, \sigma)$, we provide a detailed analysis of the commutant, in $C^* (\Sigma)$, of $C(X)$ and the commutant of the image of…

Operator Algebras · Mathematics 2011-11-22 Christian Svensson , Jun Tomiyama

We study the crossed product $C^*$-algebra associated to injective endomorphisms, which turns out to be equivalent to study the crossed product by the dilated autormorphism. We prove that the dilation of the Bernoulli $p$-shift endomorphism…

Operator Algebras · Mathematics 2013-07-16 Eduard Ortega , Enrique Pardo

We define an equivariant and equicovariant versions of the notion of module nuclearity. More precisely, for a discrete group $\Gamma$ and operator $\mathcal A$-$\Gamma$-(co)module $\mathcal B$, $\mathcal E$ over a $\Gamma$-C$^*$-algebra…

Operator Algebras · Mathematics 2024-02-20 Massoud Amini , Qing Meng

Starting with a spectral triple on a unital $C^{*}$-algebra $A$ with an action of a discrete group $G$, if the action is uniformly bounded (in a Lipschitz sense) a spectral triple on the reduced crossed product $C^{*}$-algebra $A\rtimes_{r}…

Operator Algebras · Mathematics 2022-08-30 P. Antonini , D. Guido , T. Isola , A. Rubin

To a continuous action of a vector group on a $C^*$-algebra, twisted by the imaginary exponential of a symplectic form, one associates a Rieffel deformed algebra as well as a twisted crossed product. We show that the second one is…

Operator Algebras · Mathematics 2014-06-30 I. Beltita , M. Mantoiu

Let C be a uniform clutter, i.e., all the edges of C have the same size, and let A be the incidence matrix of C. We denote the column vectors of A by v1,...,vq. The vertex covering number of C, denoted by g, is the smallest number of…

Commutative Algebra · Mathematics 2011-04-05 Luis A. Dupont , Rafael H. Villarreal

By weakening the counit and antipode axioms of a C*-Hopf algebra and allowing for the coassociative coproduct to be non-unital we obtain a quantum group, that we call a weak C*-Hopf algebra, which is sufficiently general to describe the…

q-alg · Mathematics 2009-10-28 G. Bohm , K. Szlachanyi

To a directed graph $E$ is associated a $C^*$-algebra $C^* (E)$ called a graph $C^*$-algebra. There is a canonical action $\gamma$ of ${\bf T}$ on $C^* (E)$, called the gauge action. In this paper we present necessary and sufficient…

Operator Algebras · Mathematics 2007-05-23 David Pask , Seung-Jai Rho
‹ Prev 1 8 9 10 Next ›