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Related papers: Matrix N-dilations of quantum channels

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We investigate some particular completely positive maps which admit a stable commutative Von Neumann subalgebra. The restriction of such maps to the stable algebra is then a Markov operator. In the first part of this article, we propose a…

Mathematical Physics · Physics 2015-09-17 Ivan Bardet

A dimension formula was given in [1] in order to partially classify the Lie algebras of $S$-unitary type. The natural question of when $\mathfrak{u}_{S}$ and $\mathfrak{u}_{T}$ are isomorphic is left unanswered. In this article, we will…

Rings and Algebras · Mathematics 2018-11-12 Clarisson Rizzie Canlubo

We show that a sequence $\{\Phi_n\}$ of quantum channels strongly converges to a quantum channel $\Phi_0$ if and only if there exist a common environment for all the channels and a corresponding sequence $\{V_n\}$ of Stinespring isometries…

Quantum Physics · Physics 2020-09-01 M. E. Shirokov

Stochastic dynamics of a quantum system driven by $N$ statistically independent random sudden quenches in a fixed time interval is studied. We reveal that with growing $N$ the system approaches a deterministic limit indicating…

Quantum Physics · Physics 2018-08-15 Marcin Łobejko , Jerzy Dajka , Jerzy Łuczka

Quantum channels, which are completely positive and trace preserving mappings, can alter the dimension of a system; e.g., a quantum channel from a qubit to a qutrit. We study the convex set properties of dimension-altering quantum channels,…

Quantum Physics · Physics 2016-11-22 Dong-Sheng Wang

We analyze certain class of linear maps on matrix algebras that become entanglement breaking after composing a finite or infinite number of times with themselves. This means that the Choi matrix of the iterated linear map becomes separable…

Quantum Physics · Physics 2018-06-13 Mizanur Rahaman , Samuel Jaques , Vern I. Paulsen

We study extensions of a quantum channel whose one-way capacities are described by a single-letter formula. This provides a simple technique for generating powerful upper bounds on the capacities of a general quantum channel. We apply this…

Quantum Physics · Physics 2009-02-20 Graeme Smith , John A. Smolin

We give necessary and sufficient conditions for a Gaussian quantum channel to have a dilation involving a passive, i.e., number-preserving unitary. We then establish a normal form of such channels: any passively dilatable channel is the…

Quantum Physics · Physics 2017-04-27 Martin Idel , Robert Koenig

The dynamics of quantum systems are generally described by a family of quantum channels (linear, completely positive and trace preserving maps). In this note, we mainly study the range of all possible values of…

Quantum Physics · Physics 2026-01-19 Yuan Li , Zhengli Chen , Zhihua Guo , Yongfeng Pang

For a quantum channel (completely positive, trace-preserving map), we prove a generalization to the infinite dimensional case of a result by Baumgartner and Narnhofer. This result is, in a probabilistic language, a decomposition of a…

Mathematical Physics · Physics 2016-08-03 Raffaella Carbone , Yan Pautrat

We consider a quantum channel acting on an infinite dimensional von Neumann algebra of operators on a separable Hilbert space. When there exists an invariant normal faithful state, the cyclic properties of such channels are investigated…

Operator Algebras · Mathematics 2020-02-19 Raffaella Carbone , Anna Jenčová

We present a new application of harmonic analysis to quantum information by constructing intriguing classes of quantum channels stemming from specific representations of multiplier algebras over locally compact groups $G$. Beginning with a…

Mathematical Physics · Physics 2015-06-11 Jason Crann , Matthias Neufang

We develop a construction of the unitary type anti-involution for the quantized differential calculus over $GL_q(n)$ in the case $|q|=1$. To this end, we consider a joint associative algebra of quantized functions, differential forms and…

Quantum Algebra · Mathematics 2016-10-12 Pavel Pyatov

We characterize covariant positive decomposable maps between unital C*-algebras in terms of a dilation theorem, which generalizes a seminal result by H. Scutaru from Rep. Math. Phys. 16 (1):79-87, 1979. As a case study, we provide a certain…

Operator Algebras · Mathematics 2025-12-08 Krzysztof Szczygielski

We introduce a class of linear maps irreducibly covariant with respect to the finite group generated by the Weyl operators. This group provides a direct generalization of the quaternion group. In particular, we analyze the irreducibly…

Mathematical Physics · Physics 2018-04-20 Katarzyna Siudzińska , Dariusz Chruściński

Let $\varphi$ be a normal semi-finite faithful weight on a von Neumann algebra $A$,let $(\sigma^\varphi_r)_{r\in{\mathbb R}}$ denote the modular automorphism group of $\varphi$, and let $T\colon A\to A$ be a linear map. We say that $T$…

Operator Algebras · Mathematics 2025-08-06 Charles Duquet , Christian Le Merdy

Quantum speed-ups for dynamical simulation usually demand unitary time-evolution, whereas the large ODE/PDE systems encountered in realistic physical models are generically non-unitary. We present a universal moment-fulfilling dilation that…

Quantum Physics · Physics 2025-12-23 Xiantao Li

We sketch our recent application of a non-commutative version of the Cartan `moving-frame' formalism to the quantum Euclidean space $R^N_q$, the space which is covariant under the action of the quantum group $SO_q(N)$. For each of the two…

Quantum Algebra · Mathematics 2009-10-31 B. L. Cerchiai , G. Fiore , J. Madore

Let $\K$ be an algebraic number field of degree $d$ and discriminant $\Delta$ over $\Q$. Let $\A$ be an associative algebra over $\K$ given by structure constants such that $\A\cong M_n(\K)$ holds for some positive integer $n$. Suppose that…

Rings and Algebras · Mathematics 2014-07-11 Gábor Ivanyos , Ádám D. Lelkes , Lajos Rónyai

Simulating quantum physical processes has been one of the major motivations for quantum information science. Quantum channels, which are completely positive and trace preserving processes, are the standard mathematical language to describe…

Quantum Physics · Physics 2024-02-01 Hang Li , Kai Wang , Shijie Wei , Fan Yang , Xinyu Chen , Barry C. Sanders , Dong-Sheng Wang , Gui-Lu Long