English
Related papers

Related papers: Quantum Programs as Kleisli Maps

200 papers

We introduce the notion of continuous orbit equivalence for partial dynamical systems, and give an equivalent characterization in terms of Cartan-isomorphisms for partial C*-crossed products. Both graph C*-algebras and semigroup C*-algebras…

Operator Algebras · Mathematics 2016-03-31 Xin Li

We address the classification problem for graph $C^*$-algebras of finite graphs (finitely many edges and vertices), containing the class of Cuntz-Krieger algebras as a prominent special case. Contrasting earlier work, we do not assume that…

Operator Algebras · Mathematics 2018-03-05 Søren Eilers , Gunnar Restorff , Efren Ruiz , Adam P. W. Sørensen

We consider two inclusions of $C^*$-algebras whose small $C^*$-algebras have approximate units of the large $C^*$-algebras and their two spaces of all bounded bimodule linear maps. We suppose that the two inclusions of $C^*$-algebras are…

Operator Algebras · Mathematics 2021-07-29 Kazunori Kodaka

A certain class of Frobenius algebras has been used to characterize orthonormal bases and observables on finite-dimensional Hilbert spaces. The presence of units in these algebras means that they can only be realized finite-dimensionally.…

Quantum Physics · Physics 2012-12-05 Samson Abramsky , Chris Heunen

We consider non-universal cloning maps, namely cloning transformations which are covariant under a proper subgroup G of the universal unitary group U(d), where d is the dimension of the Hilbert space H of the system to be cloned. We give a…

Quantum Physics · Physics 2009-11-07 G. M. D'Ariano , P. Lo Presti

In a recent paper, Pardo and the first named author introduced a class of C*-algebras which which are constructed from an action of a group on a graph. This class was shown to include many C*-algebras of interest, including all Kirchberg…

Operator Algebras · Mathematics 2014-06-30 Ruy Exel , Charles Starling

Closed quantum surfaces of any genus are defined as subalgebras of the Toeplitz algebra by mimicking the classical construction of identifying arcs on the boundary of the (quantum) unit disk. Isomorphism classes obtained from different…

Quantum Algebra · Mathematics 2024-07-04 Arley Sierra , Elmar Wagner

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

There are theories of coverings of $C^*$-algebras which can be included into a following list: coverings of commutative $C^*$-algebras, coverings of $C^*$-algebras of groupoids and foliations, coverings of noncommutative tori, the double…

Operator Algebras · Mathematics 2024-07-19 Petr Ivankov

We study new classes of linear preservers between C$^*$-algebras and JB$^*$-triples. Let $E$ and $F$ be JB$^*$-triples with $\partial_{e} (E_1)$. We prove that every linear map $T:E\to F$ strongly preserving Brown-Pedersen quasi-invertible…

We propose the notion of countable decomposability of maps on C*-algebras: a bounded linear map $\varphi : \mathscr{A}\to B(\mathcal{H})$, where $\mathscr{A}$ is a C*-algebra and $\mathcal{H}$ a Hilbert space, will be called countably…

Operator Algebras · Mathematics 2026-02-12 Krzysztof Szczygielski

We review the geometrical formulation of Quantum Mechanics to identify, according to Klein's programme, the corresponding group of transformations. For closed systems, it is the unitary group. For open quantum systems, the semigroup of…

Quantum Physics · Physics 2015-08-12 J. Clemente-Gallardo , G. Marmo

In a unital C*-algebra with a faithful trace functional $\tau$, the set $D_\tau(A)$ of positive $\rho\in A$ of trace \tau(\rho)=1 is an algebraic analogue of the space of density matrices (the set of all positive matrices of a fixed…

Quantum Physics · Physics 2017-10-17 Douglas Farenick , Mizanur Rahaman

We construct quantum commutators on module-algebras of quasi-triangular Hopf algebras. These are quantum-group covariant, and have generalized antisymmetry and Leibniz properties. If the Hopf algebra is triangular they additionally satisfy…

Quantum Algebra · Mathematics 2007-05-23 A. O. Garcia

We propose a unified approach to the study of isometries on algebras of vector-valued Lipschitz maps and those of continuously differentiable maps by means of the notion of admissible quadruples. We describe isometries on function spaces of…

Functional Analysis · Mathematics 2018-02-13 Osamu Hatori , Shiho Oi

We prove that von Neumann algebras and separable nuclear $C^*$-algebras are stable for the Banach-Mazur cb-distance. A technical step is to show that unital almost completely isometric maps between $C^*$-algebras are almost multiplicative…

Operator Algebras · Mathematics 2013-06-26 Eric Ricard , Jean Roydor

Let X be a path connected, compact metric space and let A be a unital separable simple nuclear Z-stable real rank zero C*-algebra. We classify all the unital *-embeddings (up to approximate unitary equivalence) of C(X) into A. Specifically,…

Operator Algebras · Mathematics 2007-09-11 P. W. Ng , Wilhelm Winter

We introduce a new class of C^*-algebras, which is a generalization of both graph algebras and homeomorphism C^*-algebras. This class is very large and also very tractable. We prove the so-called gauge-invariant uniqueness theorem and the…

Operator Algebras · Mathematics 2007-05-23 Takeshi Katsura

We prove that two finite-dimensional commutative algebras over an algebraically closed field are isomorphic if and only if they give rise to isomorphic representations of the category of finite sets and surjective maps.

Rings and Algebras · Mathematics 2011-04-05 S. S. Podkorytov

A generalization of the Pistone-Sempi argument, demonstrating the utility of non-commutative Orlicz spaces, is presented. The question of lifting positive maps defined on von Neumann algebra to maps on corresponding noncommutative Orlicz…

Operator Algebras · Mathematics 2025-03-19 Louis E. Labuschagne , Wladyslaw A. Majewski