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arXiv · 1408.1238

Nonsingular cosmology from evolutionary quantum gravity

Francesco Cianfrani·Giovanni Montani·Fabrizio Pittorino
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Abstract

We provide a cosmological implementation of the evolutionary quantum gravity, describing an isotropic Universe, in the presence of a negative cosmological constant and a massive (preinflationary) scalar field. We demonstrate that the considered Universe has a nonsingular quantum behavior, associated to a primordial bounce, whose ground state has a high occupation number. Furthermore, in such a vacuum state, the super-Hamiltonian eigenvalue is negative, corresponding to a positive emerging dust energy density. The regularization of the model is performed via a polymer quantum approach to the Universe scale factor and the proper classical limit is then recovered, in agreement with a preinflationary state of the Universe. Since the dust energy density is redshifted by the Universe deSitter phase and the cosmological constant does not enter the ground state eigenvalue, we get a late-time cosmology, compatible with the present observations, endowed with a turning point in the far future.

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Francesco Cianfrani, Giovanni Montani, Fabrizio Pittorino. 2014-10-30. Nonsingular cosmology from evolutionary quantum gravity. https://doi.org/10.1103/physrevd.90.103503

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