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About non-positive evolutions in open system dynamics

F. Benatti·R. Floreanini·M. Piani
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Abstract

The long-time evolution of a system in interaction with an external environment is usually described by a family of linear maps g_t, generated by master equations of Block-Redfield type. These maps are in general non-positive; a widely adopted cure for this physical inconsistency is to restrict the domain of definition of the dynamical maps to those states for which g_t remains positive. We show that this prescription has to be modified when two systems are immersed in the same environment and evolve with the factorized dynamics g_t x g_t starting from an entangled initial state.

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F. Benatti, R. Floreanini, M. Piani. 2003-03-05. About non-positive evolutions in open system dynamics. https://doi.org/10.1103/physreva.67.042110

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