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arXiv · 1408.4535

Bouncing scalar field cosmology in the polymeric minisuperspace picture

B. Vakili·K. Nozari·V. Hosseinzadeh·M. A. Gorji
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Abstract

We study a cosmological setup consisting of a FRW metric as the background geometry with a massless scalar field in the framework of classical polymerization of a given dynamical system. To do this, we first introduce the polymeric representation of the quantum operators. We then extend the corresponding process to reach a transformation which maps any classical variable to its polymeric counterpart. It is shown that such a formalism has also an analogue in terms of the symplectic structure, i.e., instead of applying polymerization to the classical Hamiltonian to arrive its polymeric form, one can use a new set of variables in terms of which Hamiltonian retains its form but now the corresponding symplectic structure gets a new deformed functional form. We show that these two methods are equivalent and by applying of them to the scalar field FRW cosmology see that the resulting scale factor exhibits a bouncing behavior from a contraction phase to an expanding era. Since the replacing of the big bang singularity by a bouncing behavior is one of the most important predictions of the quantum cosmological theories, we may claim that our polymerized classical model brings with itself some signals from quantum theory.

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B. Vakili, K. Nozari, V. Hosseinzadeh, M. A. Gorji. 2014-08-20. Bouncing scalar field cosmology in the polymeric minisuperspace picture. https://doi.org/10.1142/s0217732314501697

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