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arXiv · 2102.01941

On the Markov evolution of the $\rho$-matrix of a subsystem

M. A. Braun
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Abstract

Evolution of the reduced density matrix for a subsystem is studied to determine deviations from its Markov character for a system consisting of a closed chain of $N$ oscillators with one of them serving as a subsystem. The dependence on $N$ and on the coupling of the two subsystems is investigated numerically. The found deviations strongly depend on $N$ and the coupling. In the most beneficial case with $N-1=100$ and the coupling randomized in its structure the deviations fall with the evolution time up 3\%. In other cases they remain to be of the order 30\% or even more.

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M. A. Braun. 2021-02-03. On the Markov evolution of the $\rho$-matrix of a subsystem. https://arxiv.org/abs/2102.01941

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