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arXiv · 1903.09417

WKB Approximation for the Polymer Quantization of the Taub Model

Valerio Cascioli·Giovanni Montani·Riccardo Moriconi
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Abstract

We develop a suitable technical algorithm to implement a separation of the Minisuperspace configurational variables into quasi-classical and purely quantum degrees of freedom, in the framework of a Polymer quantum Mechanics reformulation of the canonical dynamics. We then implement the obtained general scheme to the specific case of a Taub Universe, in the presence of a free massless scalar field. In particular, we identify the quasi-classical variables in the Universe volume and a suitable function of the scalar field, while the purely quantum degree of freedom corresponds to the Universe anisotropy. We demonstrate that the Taub cosmology is associated to a cyclical Universe, oscillating between a minimum and maximum volume turning points, respectively. The pure quantum Universe anisotropy has always a finite value.

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Valerio Cascioli, Giovanni Montani, Riccardo Moriconi. 2019-03-22. WKB Approximation for the Polymer Quantization of the Taub Model. https://arxiv.org/abs/1903.09417

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