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Related papers: Notes on $C^{*}$-algebras

200 papers

These are notes on twisted K-homology theory and twisted Ext-theory from the C*-algebra viewpoint, part of a series of talks on ``C*-algebras, noncommutative geometry and K-theory'', primarily for physicists.

High Energy Physics - Theory · Physics 2007-05-23 V. Mathai , I. M. Singer

We provide a complete classification of the class of unital graph $C^*$-algebras - prominently containing the full family of Cuntz-Krieger algebras - showing that Morita equivalence in this case is determined by ordered, filtered…

Operator Algebras · Mathematics 2021-09-20 Søren Eilers , Gunnar Restorff , Efren Ruiz , Adam P. W. Sørensen

Gelfand - Na\u{i}mark theorem supplies a one to one correspondence between commutative $C^*$-algebras and locally compact Hausdorff spaces. So any noncommutative $C^*$-algebra can be regarded as a generalization of a topological space.…

Operator Algebras · Mathematics 2014-10-28 Petr Ivankov

It is shown that a C*-algebra generated by any faithful covariant representation of a Hilbert bimodule X is canonically isomorphic to the crossed product associated to X provided that Rieffel's induced representation functor X-ind is…

Operator Algebras · Mathematics 2015-01-30 B. K. Kwasniewski

This is the final one in the series of papers where we introduce and study the $C^*$-algebras associated with topological graphs. In this paper, we get a sufficient condition on topological graphs so that the associated $C^*$-algebras are…

Operator Algebras · Mathematics 2007-05-23 Takeshi Katsura

We provide a Cuntz-Pimsner model for graph of groups $C^*$-algebras. This allows us to compute the $K$-theory of a range of examples and show that graph of groups $C^*$-algebras can be realised as Exel-Pardo algebras. We also make a…

Operator Algebras · Mathematics 2021-07-27 Alexander Mundey , Adam Rennie

Let $K$ be a number field with ring of integers $R$. Given a modulus $\mathfrak{m}$ for $K$ and a group $\Gamma$ of residues modulo $\mathfrak{m}$, we consider the semi-direct product $R\rtimes R_{\mathfrak{m},\Gamma}$ obtained by…

Operator Algebras · Mathematics 2019-11-05 Chris Bruce

We present an introduction to modern continuous model theory with an emphasis on its interactions with topics covered in this volume such as $C^*$-algebras and von Neumann algebras. The role of ultraproducts is highlighted and expositions…

Operator Algebras · Mathematics 2023-03-08 Bradd Hart

In this paper, we introduce a C*-algebra associated to any substitution (via its Bratteli diagram model). We show that this C*-algebra contains the partial crossed product C*-algebra of the corresponding Bratteli-Vershik system and show…

Operator Algebras · Mathematics 2011-08-24 Daniel Gonçalves , Danilo Royer

This book treats: - spectral theory of Banach *-algebras, - basic representation theory of normed *-algebras, - spectral theory of representations of commutative *-algebras. A novel feature of the book is the construction of the enveloping…

Operator Algebras · Mathematics 2008-07-29 Marco Thill

Frame theory has a great revolution in recent years. This new Theory have been extended from Hilbert spaces to Hilbert C*-modules. In this paper, we introduce the notion of dual *-K-g-frames in Hilbert A-modules. Lastly we study…

Operator Algebras · Mathematics 2021-10-01 M'hamed Ghiati , Samir Kabbaj , Hatim Labrigui , Abdeslam Touri , Mohamed Rossafi

Imprimitivity theorems provide a fundamental tool for studying the representation theory and structure of crossed-product C*-algebras. In this work, we show that the Imprimitivity Theorem for induced algebras, Green's Imprimitivity Theorem…

Operator Algebras · Mathematics 2007-05-23 Siegfried Echterhoff , S. Kaliszewski , John Quigg , Iain Raeburn

A pro-C^*-algebra is a (projective) limit of C^*-algebras in the category of topological *-algebras. From the perspective of non-commutative geometry, pro-C^*-algebras can be seen as non-commutative k-spaces. An element of a pro-C^*-algebra…

Category Theory · Mathematics 2011-09-27 Rachid El Harti , Gábor Lukács

Given C*-algebras A and B and an imprimitivity A-B-bimodule X, we construct an explicit isomorphism X_* : K_i(A) --> K_i(B) where K_i denote the complex K-theory functors for i=0, 1. Our techniques do not require separability nor existence…

funct-an · Mathematics 2008-02-03 Ruy Exel

Motivated by classical facts concerning closed manifolds, we introduce a strong finiteness property in K-homology. We say that a C*-algebra has uniformly summable K-homology if all its K-homology classes can be represented by Fredholm…

Operator Algebras · Mathematics 2015-12-16 Heath Emerson , Bogdan Nica

We compute K-theory for ring C*-algebras in the case of higher roots of unity and thereby completely determine the K-theory for ring C*-algebras attached to rings of integers in arbitrary number fields.

Operator Algebras · Mathematics 2025-04-08 Xin Li , Wolfgang Lück

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

We study criteria for a ring - or more generally, for a small category - to be Gorenstein and for a module over it to be of finite projective dimension. The goal is to unify the universal coefficient theorems found in the literature and to…

K-Theory and Homology · Mathematics 2020-07-27 Ivo Dell'Ambrogio , Greg Stevenson , Jan Stovicek

We develop methods for computing graded K-theory of C*-algebras as defined in terms of Kasparov theory. We establish graded versions of Pimsner's six-term sequences for graded Hilbert bimodules whose left action is injective and by…

Operator Algebras · Mathematics 2017-06-05 Alex Kumjian , David Pask , Aidan Sims

In this paper we introduce the concepts of atomic systems for operators and K-frames in Hilbert C*-modules and we establish some results.

Operator Algebras · Mathematics 2014-03-04 Abbas Najati , M. Mohammadi Saem , P. Gavruta