Results 11 to 20 of about 296,905 (259)
Unraveling-paired dynamical maps recover the input of quantum channels
New Journal of Physics, 2023 We explore algebraic and dynamical consequences of unraveling general time-local master equations. We show that the ‘influence martingale’, the paramount ingredient of a recently discovered unraveling framework, pairs any time-local master equation with ...
Brecht Donvil +1 more
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Categories of Quantum and Classical Channels (extended abstract) [PDF]
Electronic Proceedings in Theoretical Computer Science, 2014 We introduce the CP*–construction on a dagger compact closed category as a generalisation of Selinger's CPM-construction. While the latter takes a dagger compact closed category and forms its category of "abstract matrix algebras" and completely positive
Bob Coecke +2 more
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When the Assignment Map Is Completely Positive [PDF]
Open Systems & Information Dynamics, 2018 Finding the general set of system-environment states {ρSE} for which the reduced dynamics of the system is completely positive (CP) is the subject of some recent works. An advance in this context appeared in [7], where the problem was solved for the case of CP assignment map. Here, we restate this result using the framework introduced in [8]. This, we
Iman Sargolzahi, Sayyed Yahya Mirafzali
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Construction of propagators for divisible dynamical maps
New Journal of Physics, 2021 Divisible dynamical maps play an important role in characterizing Markovianity on the level of quantum evolution. Divisible maps provide an important generalization of Markovian semigroups. Usually one analyzes either completely positive or just positive
Ujan Chakraborty, Dariusz Chruściński
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BURES DISTANCE FOR COMPLETELY POSITIVE MAPS [PDF]
Infinite Dimensional Analysis, Quantum Probability and Related Topics, 2013 Bures had defined a metric on the set of normal states on a von Neumann algebra using GNS representations of states. This notion has been extended to completely positive maps between C*-algebras by Kretschmann, Schlingemann and Werner. We present a Hilbert C*-module version of this theory.
Bhat, B. V. Rajarama, Sumesh, K.
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Electronic Proceedings in Theoretical Computer Science, 2017 In 1973 Paschke defined a factorization for completely positive maps between C*-algebras. In this paper we show that for normal maps between von Neumann algebras, this factorization has a universal property, and coincides with Stinespring's dilation for ...
Abraham Westerbaan, Bas Westerbaan
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Canonical structure of A and B maps
Quanta, 2021 In their seminal 1961 paper, Sudarshan, Mathews and Rau investigated properties of the dynamical A and B maps acting on n-dimensional quantum systems. The nature of dynamical maps in open quantum system evolutions has attracted great deal of attention ...
Sudha Sudha +3 more
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There Are Many More Positive Maps Than Completely Positive Maps [PDF]
International Mathematics Research Notices, 2017 Abstract A $\ast$-linear map $\Phi$ between matrix spaces is positive if it maps positive semidefinite matrices to positive semidefinite ones, and is called completely positive if all its ampliations $I_n\otimes \Phi$ are positive. In this article, quantitative bounds on the fraction of positive maps that are completely positive are ...
Klep, Igor +3 more
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Completely Positive Maps [PDF]
, 2003 We have seen that C*-algebras boast a number of good structural properties that distinguish them from arbitrary Banach algebras. There are various types of maps one could consider between C*-algebras which aim at preserving particular C*-algebraic properties.
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Positive maps that are not completely positive [PDF]
Physical Review A, 2000 The concept of the {\em half density matrix} is proposed. It unifies the quantum states which are described by density matrices and physical processes which are described by completely positive maps. With the help of the half-density-matrix representation of Hermitian linear map, we show that every positive map which is not completely positive is a ...
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