English
Related papers

Related papers: Covariant decomposable maps on C*-algebras and qua…

200 papers

Positivity or the stronger notion of complete positivity, and contextuality are central properties of quantum dynamics. In this work, we demonstrate that a physical unitary-universe dilation model could be employed to characterize the…

Quantum Physics · Physics 2013-03-22 Song Cheng , Dongsheng Wang

We analyze bipartite matrices and linear maps between matrix algebras, which are respectively, invariant and covariant, under the diagonal unitary and orthogonal groups' actions. By presenting an expansive list of examples from the…

Quantum Physics · Physics 2021-08-11 Satvik Singh , Ion Nechita

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 notion of completely positive invariant conjugate-bilinear map in a partial *-algebra is introduced and a generalized Stinespring theorem is proven. Applications to the existence of integrable extensions of *-representations of…

Mathematical Physics · Physics 2009-04-07 F. Bagarello , A. Inoue , C. Trapani

The generalized state space of a commutative C*-algebra, denoted S_H(C(X)), is the set of positive unital maps from C(X) to the algebra B(H) of bounded linear operators on a Hilbert space H. C*-convexity is one of several non-commutative…

Operator Algebras · Mathematics 2009-02-12 M. C. Gregg

Any deformation of a Weyl or Clifford algebra A can be realized through a `deforming map', i.e. a formal change of generators in A. This is true in particular if A is covariant under a Lie algebra g and its deformation is induced by some…

q-alg · Mathematics 2009-10-30 Gaetano Fiore

Graph C*-algebras have been celebrated as C*-algebras that can be seen, because many important properties may be determined by looking at the underlying graph. This paper introduces the permutation graph for a permutative endomorphism of a…

Operator Algebras · Mathematics 2015-01-15 James Emil Avery , Rune Johansen , Wojciech Szymanski

We consider a net of *-algebras, locally around any point of observation, equipped with a natural partial order related to the isotony property. Assuming the underlying manifold of the net to be a differentiable, this net shall be…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Rainer , H. Salehi

It is shown that the operator space generated by peripheral eigenvectors of a unital completely positive map on a von Neumann algebra has a $C^*$-algebra structure. This extends the notion of non-commutative Poisson boundary by including…

Operator Algebras · Mathematics 2024-05-24 B. V. Rajarama Bhat , Samir Kar , Bharat Talwar

We develop a completely bounded counterpart to the non-commutative Choquet boundary of an operator space. We show how the class of completely bounded linear maps is too large to accommodate our purposes. To overcome this obstacle, we…

Operator Algebras · Mathematics 2018-03-01 Raphaël Clouâtre , Christopher Ramsey

We show that shift equivalence of essential adjacency matrices coincides with gauge-equivariant homotopy equivalence of their stabilized graph C*-algebras. This provide the first equivalent formulation of shift equivalence of essential…

Operator Algebras · Mathematics 2024-08-27 Boris Bilich , Adam Dor-On , Efren Ruiz

We prove that a unital completely positive map between finite-dimensional C*-algebras is a homomorphism if and only if it is completely entropy-nonincreasing, where the relevant notion of entropy is a variant of von Neumann entropy. This…

Operator Algebras · Mathematics 2025-01-22 Andre Kornell

In this paper, we discuss positive maps induced by (irreducibly) covariant linear operators for finite groups. The application of group theory methods allows deriving some new results of a different kind. In particular, a family of…

Quantum Physics · Physics 2020-09-07 Piotr Kopszak , Marek Mozrzymas , Michał Studziński

We define the notion of invariant derivation of a C*-algebra under a compact quantum group action and prove that in certain conditions, such derivations are generators of one parameter automorphism groups.

Operator Algebras · Mathematics 2007-05-23 R. Dumitru , C. Peligrad

We show that nuclear C*-algebras have a refined version of the completely positive approximation property, in which the maps that approximately factorize through finite dimensional algebras are convex combinations of order zero maps. We use…

Operator Algebras · Mathematics 2012-04-27 Ilan Hirshberg , Eberhard Kirchberg , Stuart White

This is a continuation of the study of the theory of quantum stochastic dilation of completely positive semigroups on a von Neumann or $C^*$ algebra, here with unbounded generators. The additional assumption of symmetry with respect to a…

Mathematical Physics · Physics 2007-05-23 Debashish Goswami , Kalyan B. Sinha

We prove a covariant version of the KSGNS (Kasparov, Stinespring, Gel'fand,Naimark,Segal) construction for completely positive linear maps between locally $C^{*}$-algebras. As an application of this construction, we show that a covariant…

Operator Algebras · Mathematics 2007-05-23 Maria Joita

Dilation theory is a paradigm for studying operators by way of exhibiting an operator as a compression of another operator which is in some sense well behaved. For example, every contraction can be dilated to (i.e., is a compression of) a…

Operator Algebras · Mathematics 2020-02-18 Orr Shalit

We consider three quantum algebras: the q-oscillator algebra, the Podles' sphere and the q-deformed enveloping algebra of $su(2).$ To each of these *-algebras we associate certain partial dynamical system and perform the "Mackey analysis"…

Operator Algebras · Mathematics 2012-06-14 Philip A. Dowerk , Yurii Savchuk

We study dilations of finite tuples of normal, completely positive and completely contractive maps (which we call CP-maps) acting on a von Neumann algebra, and commuting according to a graph G. We show that if G is acyclic, then a tuple…

Operator Algebras · Mathematics 2021-08-16 Alexander Vernik