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arXiv · 1706.06069

Mixed Quantum States with Variable Planck Constant

Maurice de Gosson
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Abstract

Recent cosmological measurements tend to confirm that the fine structure constant α is not immutable and has undergone a tiny variation since the Big Bang. Choosing adequate units, this could also reflect a variation of Planck's constant h. The aim of this Letter is to explore some consequences of such a possible change of h for the pure and mixed states of quantum mechanics. Surprisingly enough it is found that not only is the purity of a state extremely sensitive to such changes, but that quantum states can evolve into classical states, and vice versa. A complete classification of such transitions is however not possible for the moment being because of yet unsolved mathematical difficulties related to the study of positivity properties of trace class operators.

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Maurice de Gosson. 2017-07-20. Mixed Quantum States with Variable Planck Constant. https://doi.org/10.1016/j.physleta.2017.07.035

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