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arXiv · 1212.4387

Vanishing quantum discord is not necessary for completely-positive maps

Aharon Brodutch·Animesh Datta·Kavan Modi·Ángel Rivas·César A. Rodríguez-Rosario
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Abstract

The description of the dynamics of a system that may be correlated with its environment is only meaningful within the context of a specific framework. Different frameworks rely upon different assumptions about the initial system-environment state. We reexamine the connections between complete-positivity and quantum discord within two different sets of assumptions about the relevant family of initial states. We present an example of a system-environment state with non-vanishing quantum discord that leads to a completely-positive map. This invalidates an earlier claim on the necessity of vanishing quantum discord for completely-positive maps. In our final remarks we discuss the physical validity of each approach.

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Aharon Brodutch, Animesh Datta, Kavan Modi, Ángel Rivas, César A. Rodríguez-Rosario. 2013-04-04. Vanishing quantum discord is not necessary for completely-positive maps. https://doi.org/10.1103/physreva.87.042301

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