Comment on ``Dynamics of open quantum systems initially entangled with environment: Beyond the Kraus representation'' [PRA 64, 062106 (2001)]

摘要

We correct a mistake in a result reported in [PRA 64, 062106 (2001)], whereit is rightfully argued that initial correlations between a system and itsenvironment may render the system reduced dynamics not completely positive. Weprove how not only these initial correlations but also the specific jointdynamics does play a significant role in the question of the complete positivyof the reduced dynamics.