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Time Scale and Completely Positive Dynamical Evolutions

B. Vacchini
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Abstract

It is argued that in the description of macroscopic systems inside quantum mechanics the study of the dynamics of selected degrees of freedom slowly varying on a suitable time scale, corresponding to relevant observables for the given reduced description, is particularly meaningful. A formalism developing these ideas in the more simple case of a microsystem interacting with a macroscopic system is briefly outlined, together with an application to the field of neutron optics. The obtained reduced description relies on a T-matrix formalism and has the property of complete positivity.

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B. Vacchini. 2002-11-20. Time Scale and Completely Positive Dynamical Evolutions. https://arxiv.org/abs/quant-ph/0211128

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