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arXiv · 1711.02627

Quantum to classical transition in the Hořava-Lifshitz quantum cosmology

Abstract

A quasi-Gaussian quantum superposition of Hořava-Lifshitz (HL) stationary states is built in order to describe the transition of the quantum cosmological problem to the related classical dynamics. The obtained HL phase-space superposed Wigner function and its associated Wigner currents describe the conditions for the matching between classical and quantum phase-space trajectories. The matching quantum superposition parameter is associated to the total energy of the classical trajectory which, at the same time, drives the engendered Wigner function to the classical stationary regime. Through the analysis of the Wigner flows, the quantum fluctuations that distort the classical regime can be quantified as a measure of (non)classicality. Finally, the modifications to the Wigner currents due to the inclusion of perturbative potentials are computed in the HL quantum cosmological context. In particular, the inclusion of a cosmological constant provides complementary information that allows for connecting the age of the Universe with the overall stiff matter density profile.

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BibTeXRIS

Alex E. Bernardini, Pedro Leal, Orfeu Bertolami. 2018-02-03. Quantum to classical transition in the Hořava-Lifshitz quantum cosmology. https://doi.org/10.1088/1475-7516%2F2018%2F02%2F025

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