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Related papers: A note on two-sided ideals in locally C*-algebras

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Let A be a unital separable C*-algebra. We observe that A is type I if and only if the CNT-entropy of every inner automorphism of A is zero.

Operator Algebras · Mathematics 2007-05-23 Nathanial P. Brown

The local multiplier C*-algebra M_{loc}(A) of any C*-algebra A can *-isomorphicly embedded into the injective envelope I(A) of A in such a way that the canonical embeddings of A into both these C*-algebras are identified. If A is…

Operator Algebras · Mathematics 2025-05-08 Michael Frank

We prove a number of results having to do with equipping type-I $\mathrm{C}^*$-algebras with compact quantum group structures, the two main ones being that such a compact quantum group is necessarily co-amenable, and that if the…

Operator Algebras · Mathematics 2020-08-11 Alexandru Chirvasitu , Jacek Krajczok , Piotr M. Sołtan

Let $A=B+C$ be an associative algebra graded by a group $G$, which is a sum of two homogeneous subalgebras $B$ and $C$. We prove that if $B$ is an ideal of $A$, and both $B$ and $C$ satisfy graded polynomial identities, then the same…

Rings and Algebras · Mathematics 2023-07-13 Pedro Fagundes , Plamen Koshlukov

Let $M$ be a maximal subalgebra of a Lie algebra $L$ and $A/B$ a chief factor of $L$ such that $B \subseteq M$ and $A \not \subseteq M$. We call the factor algebra $M \cap A/B$ a $c$-section of $M$. All such $c$-sections are isomorphic, and…

Rings and Algebras · Mathematics 2014-12-03 David A. Towers

Given two C*-algebras A and B, abstract A-B bimodules that can be isometrically represented as operator bimodules are characterised in terms of their norm. Various properties of such bimodules are given. Their theory is very similar to…

Operator Algebras · Mathematics 2007-05-23 C. Pop

We propose a definition of what should be meant by a {\it proper} action of a locally compact group on a C*-algebra. We show that when the C*-algebra is commutative this definition exactly captures the usual notion of a proper action on a…

Operator Algebras · Mathematics 2007-05-23 Marc A. Rieffel

We show that if two tensor algebras of topological graphs are algebraically isomorphic, then the graphs are locally conjugate. Conversely, if the base space is at most one dimensional and the edge space is compact, then locally conjugate…

Operator Algebras · Mathematics 2010-04-06 Kenneth R. Davidson , Jean Roydor

We construct a unital pre-C*-algebra $A_0$ which is stably finite, in the sense that every left invertible square matrix over $A_0$ is right invertible, while the C*-completion of $A_0$ contains a non-unitary isometry, and so it is…

Operator Algebras · Mathematics 2017-09-01 Niels Jakob Laustsen , Jared T. White

We consider three lifting questions: Given a $C\sp{*}$-algebra $I$, if there is a unital $C\sp{*}$-algebra $A$ contains $I$ as an ideal, is every unitary from $A/I$ lifted to a unitary in $A$? is every unitary from $A/I$ lifted to an…

Operator Algebras · Mathematics 2008-11-11 Hyun Ho Lee

Some affirmative answers are given to Huneke's problems. The calculation of local cohomology modules with respect to an arbitrary pair of ideals $I,J$ can be reduced to calculation of local cohomology modules with respect to a pair of…

Commutative Algebra · Mathematics 2014-07-21 M. Aghapournahr , Kh. Ahmadi-amoli , M. Y. Sadeghi

The class of separable C*-algebras which can be written as inductive limits of continuous-trace C*-algebras with spectrum homeomorphic to a disjoint union of trees and trees with a point removed is classified by the Cuntz semigroup.

Operator Algebras · Mathematics 2010-04-05 Alin Ciuperca , George A. Elliott , Luis Santiago

In this paper, by analogy with the case of C*-algebras, we define the notion of induced representation of a locally C*-algebra, and then we prove a imprimitivity theorem for induced representations of locally C*-algebras.

Operator Algebras · Mathematics 2007-05-23 Maria Joita

We introduce and analyse the structure of C*-algebras arising from ideals in right tensor C*-precategories, which naturally generalize both relative Cuntz-Pimsner and Doplicher-Roberts algebras. We establish an explicit intrinsic…

Operator Algebras · Mathematics 2013-08-27 B. K. Kwaśniewski

The following topics are presented in these notes: Elements of Banach algebras, Banach algebras of the form $L^1(G)$, where $G$ is a locally compact group, spectrum of elements of Banach algebras, the spectral theory of compact operators on…

Operator Algebras · Mathematics 2021-10-13 Vahid Shirbisheh

Let $J_G$ denote the binomial edge ideal of a connected undirected graph on $n$ vertices. This is the ideal generated by the binomials $x_iy_j - x_jy_i, 1\leq i < j \leq n,$ in the polynomial ring $S= K[x_1,...,x_n,y_1,...,y_n]$ where…

Commutative Algebra · Mathematics 2013-01-07 Peter Schenzel , Sohail Zafar

Let $I\supsetneq J$ be two monomial ideals of a polynomial algebra over a field generated in degree $\geq d$, resp. $\geq d+1$ . We study when the Stanley Conjecture holds for $I/J$ using the recent result of \cite{IKM} concerning the…

Commutative Algebra · Mathematics 2014-04-25 Dorin Popescu

We classify extensions of certain classifiable C*-algebras using the six term exact sequence in K-theory together with the positive cone of the K_0-groups of the distinguished ideal and quotient. We then apply our results to a class of…

Operator Algebras · Mathematics 2014-10-01 Soren Eilers , Gunnar Restorff , Efren Ruiz

The adjoint of an ideal I in a regular local ring R is the R-ideal adj(I):=H^0(Y, I\omega_Y), where f:Y -> Spec(R) is a proper birational map with Y nonsingular and IO_Y invertible, and \omega_f is a canonical relative dualizing sheaf.…

alg-geom · Mathematics 2008-02-03 Joseph Lipman

Let $H$ be a separable Hilbert space with a fixed orthonormal basis. Let $\mathbb B^{(k)}(H)$ denote the set of operators, whose matrices have no more than $k$ non-zero entries in each line and in each column. The closure of the union (over…

Operator Algebras · Mathematics 2018-08-21 Vladimir Manuilov