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arXiv · 1710.11159

Non-classicality from the phase-space flow analysis of the Weyl-Wigner quantum mechanics

Alex E. Bernardini·Orfeu Bertolami
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Abstract

A fluid analog of the information flux in the phase-space associated to purity and von Neumann entropy are identified in the Weyl-Wigner formalism of quantum mechanics. Once constrained by symmetry and positiveness, the encountered continuity equations provide novel quantifiers for non-classicality (non-Liouvillian fluidity) given in terms of quantum decoherence, purity and von Neumann entropy fluxes. Through definitions in the Weyl-Wigner formalism, one can identify the quantum fluctuations that distort the classical-quantum coincidence regime, and the corresponding quantum information profile, whenever some bounded $x-p$ volume of the phase-space is specified. The dynamics of anharmonic systems is investigated in order to illustrate such a novel paradigm for describing quantumness and classicality through the flux of quantum information in the phase-space.

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Alex E. Bernardini, Orfeu Bertolami. 2017-10-30. Non-classicality from the phase-space flow analysis of the Weyl-Wigner quantum mechanics. https://doi.org/10.1209/0295-5075%2F120%2F20002

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