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arXiv · 1111.4595

Nonsingular, big-bounce cosmology from spinor-torsion coupling

Nikodem Poplawski
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Abstract

The Einstein-Cartan-Sciama-Kibble theory of gravity removes the constraint of general relativity that the affine connection be symmetric by regarding its antisymmetric part, the torsion tensor, as a dynamical variable. The minimal coupling between the torsion tensor and Dirac spinors generates a spin-spin interaction which is significant in fermionic matter at extremely high densities. We show that such an interaction averts the unphysical big-bang singularity, replacing it with a cusp-like bounce at a finite minimum scale factor, before which the Universe was contracting. This scenario also explains why the present Universe at largest scales appears spatially flat, homogeneous and isotropic.

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Nikodem Poplawski. 2012-07-04. Nonsingular, big-bounce cosmology from spinor-torsion coupling. https://doi.org/10.1103/physrevd.85.107502

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