Completely positive maps and classical correlations

@article{RodriguezRosario2008CompletelyPM,
title={Completely positive maps and classical correlations},
author={C'esar A. Rodr'iguez-Rosario and K. Modi and Aik-meng Kuah and Anil Shaji and E. Sudarshan},
journal={Journal of Physics A},
year={2008},
volume={41},
pages={205301}
}

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 [1]. We prove that initial states that have only classical correlations lead to completely positive reduced dynamics. The induced maps can be not completely positive when quantum correlations including, but not limited to… Expand