English
Related papers

Related papers: Some classes of topological quasi *-algebras

200 papers

The notion of bounded element of C*-inductive locally convex spaces (or C*-inductive partial *-algebras) is introduced and discussed in two ways: the first one takes into account the inductive structure provided by certain families of…

Operator Algebras · Mathematics 2013-07-29 Giorgia Bellomonte , Salvatore Di Bella , Camillo Trapani

A triangular limit algebra A is isometrically isomorphic to the tensor algebra of a C*-correspondence if and only if its fundamental relation R(A) is a tree admitting a $Z^+_0$-valued continuous and coherent cocycle. For triangular limit…

Operator Algebras · Mathematics 2017-05-17 Elias Katsoulis , Chris Ramsey

Noncommutative tori with real multiplication are the irrational rotation algebras that have special equivalence bimodules. Y. Manin proposed the use of noncommutative tori with real multiplication as a geometric framework for the study of…

Operator Algebras · Mathematics 2009-04-08 Norio Nawata

We show that unital simple C*-algebras with tracial topological rank zero which are locally approximated by subhomogeneous C^-algebras can be classified by their ordered $K$-theory. We apply this classification result to show that certain…

Operator Algebras · Mathematics 2007-05-23 Huaxin Lin

Let H be a finite-dimensional quasibialgebra. We show that H is a quasi-Hopf algebra if and only if the category of its finite-dimensional left modules is rigid if and only if a structure theorem for Hopf modules over H holds. We also show…

Quantum Algebra · Mathematics 2007-05-23 Peter Schauenburg

A detailed study of the semigroup $C^\ast$-algebra is presented. This $C^\ast$-algebra appears as a "deformation" of the continuous functions algebra on a compact abelian group. Considering semigroup $C^\ast$-algebras in this framework we…

Operator Algebras · Mathematics 2013-05-28 Marat Aukhadiev , Suren Grigoryan , Ekaterina Lipacheva

We explore various limit constructions for C*-algebras, such as composition series and inverse limits, in relation to the notions of real rank, stable rank, and extremal richness. We also consider extensions and pullbacks. We identify some…

Operator Algebras · Mathematics 2017-06-09 Lawrence G. Brown , Gert K. Pedersen

In this paper we study the C*-algebras associated to continuous fields over locally compact metrisable zero dimensional spaces whose fibers are Kirchberg C*-algebras satisfying the UCT. We show that these algebras are inductive limits of…

Operator Algebras · Mathematics 2007-05-23 Marius Dadarlat , Cornel Pasnicu

We study the validity of the Blackadar-Kirchberg conjecture for extensions of separable, nuclear, quasidiagonal $C^*$-algebras that satisfy the UCT. More specifically, we show that the conjecture for the extension has an affirmative answer…

Operator Algebras · Mathematics 2022-09-30 Iason Moutzouris

We introduce quasi-Hopf $*$-algebras i.e. quasi-Hopf algebras equipped with a conjugation (star) operation. The definition of quasi-Hopf $*$-algebras proposed ensures that the class of quasi-Hopf $*$-algebras is closed under twisting and…

Quantum Algebra · Mathematics 2007-05-23 M. D. Gould , T. Lekatsas

We exhibit examples of simple separable nuclear C*-algebras, along with actions of the circle group and outer actions of the integers, which are not equivariantly isomorphic to their opposite algebras. In fact, the fixed point subalgebras…

Operator Algebras · Mathematics 2016-02-16 Marius Dadarlat , Ilan Hirshberg , N. Christopher Phillips

We continue our investigation, from \cite{dh}, of the ring-theoretic infiniteness properties of ultrapowers of Banach algebras, studying in this paper the notion of being purely infinite. It is well known that a $C^*$-algebra is purely…

Functional Analysis · Mathematics 2022-04-07 Matthew Daws , Bence Horváth

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

We carefully define and study C*-algebras over topological spaces, possibly non-Hausdorff, and review some relevant results from point-set topology along the way. We explain the triangulated category structure on the bivariant Kasparov…

K-Theory and Homology · Mathematics 2015-10-23 Ralf Meyer , Ryszard Nest

Complexity rank for $C^*$-algebras was introduced by the second author and Yu for applications towards the UCT: very roughly, this rank is at most $n$ if you can repeatedly cut the $C^*$-algebra in half at most $n$ times, and end up with…

Operator Algebras · Mathematics 2022-10-13 Arturo Jaime , Rufus Willett

In this note we analyze the C*-algebra associated with a branched covering both as a groupoid C*-algebra and as a Cuntz-Pimsner algebra. We determine conditions when the algebra is simple and purely infinite. We indicate how to compute the…

Operator Algebras · Mathematics 2007-05-23 Valentin Deaconu , Paul S. Muhly

We examine the question of quasidiagonality for C*-algebras of discrete amenable groups from a variety of angles. We give a quantitative version of Rosenberg's theorem via paradoxical decompositions and a characterization of…

Operator Algebras · Mathematics 2013-06-19 José Carrión , Marius Dadarlat , Caleb Eckhardt

This work provides a generalization of the Gelfand duality to the context of noncommutative locally $C^*$ algebras. Using a reformulation of a theorem proven by Dauns and Hofmann in the 60's we show that every locally $C^*$ algebra can be…

Operator Algebras · Mathematics 2013-07-18 Michael Forger , Daniel V. Paulino

The pro-algebraic fundamental group can be understood as a completion with respect to finite-dimensional non-commutative algebras. We introduce finer invariants by looking at completions with respect to Banach and C*-algebras, from which we…

Algebraic Geometry · Mathematics 2017-03-29 J. P. Pridham

Let H be a full Hilbert bimodule over a C*-algebra A. We show that the Cuntz-Pimsner C*-algebra associated to H is exact if and only if A is exact. Using this result, we give alternative proofs for exactness of reduced amalgamated free…

Operator Algebras · Mathematics 2007-05-23 Ken Dykema , Dimitri Shlyakhtenko