Results 21 to 30 of about 296,905 (259)
On the Alberti-Uhlmann Condition for Unital Channels [PDF]
Quantum, 2020 We address the problem of existence of completely positive trace preserving (CPTP) maps between two sets of density matrices. We refine the result of Alberti and Uhlmann and derive a necessary and sufficient condition for the existence of a unital ...
Sagnik Chakraborty +3 more
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Quantum Weak Invariants: Dynamical Evolution of Fluctuations and Correlations
Entropy, 2020 Weak invariants are time-dependent observables with conserved expectation values. Their fluctuations, however, do not remain constant in time. On the assumption that time evolution of the state of an open quantum system is given in terms of a completely ...
Zeyi Shi, Sumiyoshi Abe
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Infinite-Dimensionality in Quantum Foundations: W*-algebras as Presheaves over Matrix Algebras [PDF]
Electronic Proceedings in Theoretical Computer Science, 2017 In this paper, W*-algebras are presented as canonical colimits of diagrams of matrix algebras and completely positive maps. In other words, matrix algebras are dense in W*-algebras.
Mathys Rennela +2 more
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Completely positive maps and classical correlations [PDF]
Journal of Physics A: Mathematical and Theoretical, 2008 We expand the set of initial states of a system and its environment that are known to guarantee completely positive reduced dynamics for the system when the combined state evolves unitarily. We characterize the correlations in the initial state in terms of its quantum discord [H. Ollivier and W. H. Zurek, Phys. Rev. Lett. 88, 017901 (2001)].
Rodríguez-Rosario, César A. +4 more
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Extremal problems for completely positive maps
International Journal of Mathematics and Mathematical Sciences, 1994 In this note, we study the faces of some convex subsets of CPc(A,B(ℋ))(the continuous completely positive linear maps from pro-C*-algebra A to B(ℋ)).
Mingze Yang
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Time inhomogeneous quantum dynamical maps
Scientific Reports, 2022 We discuss a wide class of time inhomogeneous quantum evolution which is represented by two-parameter family of completely positive trace-preserving maps. These dynamical maps are constructed as infinite series of jump processes.
Dariusz Chruściński
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Completely positive module maps and completely positive extreme maps [PDF]
Proceedings of the American Mathematical Society, 1996 Let A , B A,B
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Approximating quantum channels by completely positive maps with small Kraus rank [PDF]
QuantumWe study the problem of approximating a quantum channel by one with as few Kraus operators as possible (in the sense that, for any input state, the output states of the two channels should be close to one another).
Cécilia Lancien, Andreas Winter
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Divisibility of qubit channels and dynamical maps [PDF]
Quantum, 2019 The concept of divisibility of dynamical maps is used to introduce an analogous concept for quantum channels by analyzing the simulability of channels by means of dynamical maps.
David Davalos +2 more
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A completely positive map associated with a positive map [PDF]
Pacific Journal of Mathematics, 2011 We show that each positive map from B(K) to B(H) with K and H finite dimensional Hilbert spaces is a scalar multiple of a map of the form $Tr - ψ$ with $ψ$ completely positive. This is used to give necessary and sufficient conditions for maps to be C-positive for a large class of mapping cones; in particular we apply the results to k-positive maps.
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