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arXiv · 1906.11824

Analysis of big bounce in Einstein--Cartan cosmology

Jordan L. Cubero·Nikodem J. Popławski
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Abstract

We analyze the dynamics of a homogeneous and isotropic universe in the Einstein--Cartan theory of gravity. The spin of fermions produces spacetime torsion that prevents gravitational singularities and replaces the big bang with a nonsingular big bounce. We show that a closed universe exists only when a particular function of its scale factor and temperature is higher than some threshold value, whereas an open and a flat universes do not have such a restriction. We also show that a bounce of the scale factor is double: as the temperature increases and then decreases, the scale factor decreases, increases, decreases, and then increases.

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Jordan L. Cubero, Nikodem J. Popławski. 2019-06-27. Analysis of big bounce in Einstein--Cartan cosmology. https://doi.org/10.1088/1361-6382%2Fab5cb9

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