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Information measures and classicality in quantum mechanics

C. Anastopoulos
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Abstract

We study information measures in quantu mechanics, with particular emphasis on providing a quantification of the notions of classicality and predictability. Our primary tool is the Shannon - Wehrl entropy I. We give a precise criterion for phase space classicality and argue that in view of this a) I provides a measure of the degree of deviation from classicality for closed system b) I - S (S the von Neumann entropy) plays the same role in open systems We examine particular examples in non-relativistic quantum mechanics. Finally, (this being one of our main motivations) we comment on field classicalisation on early universe cosmology.

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C. Anastopoulos. 1998-05-19. Information measures and classicality in quantum mechanics. https://doi.org/10.1103/physrevd.59.045001

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