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arXiv · 2108.06200

Requiring linearity leads to complete positivity

Iman Sargolzahi
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Abstract

The reduced dynamics of an open quantum system $S$, interacting with its environment $E$, is not completely positive, in general. In this paper, we demonstrate that if the two following conditions are satisfied, simultaneously, then the reduced dynamics is completely positive: (1) the reduced dynamics of the system is linear, for arbitrary system-environment unitary evolution $U$; and (2) the reduced dynamics of the system is linear, for arbitrary initial state of the system $ρ_S$.

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Iman Sargolzahi. 2022-09-12. Requiring linearity leads to complete positivity. https://doi.org/10.1103/physreva.106.032205

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