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Related papers: Extensions of C*-algebras by partial isometries

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We exhibit a family of *-isomorphisms mapping the CAR algebra onto its even subalgebra.

Mathematical Physics · Physics 2008-11-06 Carsten Binnenhei

We provide some background on the category of classifiable $\mathrm{C}^*$-algebras, whose objects are infinite-dimensional, simple, separable, unital $\mathrm{C}^*$-algebras that have finite nuclear dimension and satisfy the universal…

Operator Algebras · Mathematics 2025-12-09 Bhishan Jacelon

We shall consider a locally compact groupoid endowed with a Haar system and having proper orbit space. We shall construct a groupoid C*-algebra which is independent of the Haar system (up to a *-isomorphism).

Operator Algebras · Mathematics 2007-05-23 Madalina Roxana Buneci

We study bounded bilinear maps on a C$^*$-algebra $A$ having product property at $c\in A$. This leads us to the question of when a C$^*$-algebra is determined by products at $c.$ In the first part of our paper, we investigate this question…

Operator Algebras · Mathematics 2023-12-04 Jorge J. Garcés , Mykola Khrypchenko

We give a sufficient condition for a $^*$-algebra with a specified basis to have an enveloping $C^*$-algebra. Particularizing to the setting of a Hecke algebra $\h(G,\gm)$, we show that under a suitable assumption not only we can assure…

Operator Algebras · Mathematics 2012-11-30 Rui Palma

In this paper, we realize C*-algebras of generalized Boolean dynamical systems as partial crossed products. Reciprocally, we give some sufficient conditions for a partial crossed product to be isomorphic to a C*-algebra of a generalized…

Operator Algebras · Mathematics 2022-02-07 Gilles G. de Castro , Eun Ji Kang

We study C*-algebra endomorphims which are special in a weaker sense w.r.t. the notion introduced by Doplicher and Roberts. We assign to such endomorphisms a geometrical invariant, representing a cohomological obstruction for them to be…

Operator Algebras · Mathematics 2011-11-21 Ezio Vasselli

To a large class of graphs of groups we associate a C*-algebra universal for generators and relations. We show that this C*-algebra is stably isomorphic to the crossed product induced from the action of the fundamental group of the graph of…

Operator Algebras · Mathematics 2021-07-27 Nathan Brownlowe , Alexander Mundey , David Pask , Jack Spielberg , Anne Thomas

Let $\mathcal A$ be a separable, unital, approximately divisible C$^*$-algebra. We show that $\mathcal A$ is generated by two self-adjoint elements and the topological free entropy dimension of any finite generating set of $\mathcal A$ is…

Operator Algebras · Mathematics 2008-04-21 Weihua Li , Junhao Shen

We show that a $C^*$-algebra $\mathfrak{A}$ which is stably isomorphic to a unital graph $C^*$-algebra, is isomorphic to a graph $C^*$-algebra if and only if it admits an approximate unit of projections. As a consequence, a hereditary…

Operator Algebras · Mathematics 2017-02-01 Sara E. Arklint , James Gabe , Efren Ruiz

A characterization is given for directed graphs that yield graph $C^*$-algebras with continuous trace. This is established for row-finite graphs with no sources first using a groupoid approach, and extended to the general case via the…

Operator Algebras · Mathematics 2015-12-15 Danny Crytser

In this paper, for a given finitely generated algebra (an algebraic structure with arbitrary operations and no predicates) A we study finitely generated limit algebras of A, approaching them via model theory and algebraic geometry. Along…

Algebraic Geometry · Mathematics 2008-08-20 E. Daniyarova , A. Myasnikov , V. Remeslennikov

Kadison and Kastler introduced a metric on the set of all C$^*$-algebras on a fixed Hilbert space. In this paper structural properties of C$^*$-algebras which are close in this metric are examined. Our main result is that the property of…

Operator Algebras · Mathematics 2010-08-16 Erik Christensen , Allan Sinclair , Roger R. Smith , Stuart White

In this paper we continue the analysis undertaken in a series of previous papers on structures arising as completions of C*-algebras under topologies coarser that their norm and we focus our attention on the so-called {\em locally convex…

Mathematical Physics · Physics 2015-10-27 Camillo Trapani , Salvatore Triolo

This paper studies direct limits of full upper triangular matrix algebras with embeddings which are not *-extendible. A representation of the limit algebra is found so that the generated C*-algebra is the C*-envelope. Some examples are…

funct-an · Mathematics 2008-02-03 Alan Hopenwasser , Cecelia Laurie

Representations of $C^*$-algebras are realized on section spaces of holomorphic homogeneous vector bundles. The corresponding section spaces are investigated by means of a new notion of reproducing kernel, suitable for dealing with…

Operator Algebras · Mathematics 2008-02-22 Daniel Beltita , Jose E. Gale

Let $a$ be a positive element in a unital $C^*$-algebra $\mathfrak{A}$. We define a semi-norm on $\mathfrak{A}$, which generalizes the $a$-operator semi-norm and the $a$-numerical radius. We investigate basic properties of this semi-norm…

Operator Algebras · Mathematics 2022-11-01 Mohamed Mabrouk , Ali Zamani

In this article, we study Dorroh extensions of algebras and Dorroh extensions of coalgebras. Their structures are described. Some properties of these extensions are presented. We also introduce the finite duals of algebras and modules which…

Rings and Algebras · Mathematics 2020-07-07 Lan You , Hui-Xiang Chen

What is a vector field on a C*-algebra is defined. Its relation to semigroups of endomorphisms was researched. Some results given about those vector fields and semigroups. There are also various constructions of semigroups including one…

Mathematical Physics · Physics 2012-12-04 Innocenti Maresin

We give a new very concrete description of the C*-envelope of the tensor algebra associated to multivariable dynamical system. In the surjective case, this C*-envelope is described as a crossed product by an endomorphism, and as a groupoid…

Operator Algebras · Mathematics 2008-12-02 K. R. Davidson , J. Roydor
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