Nonsingular, big-bounce cosmology from spinor-torsion coupling

  title={Nonsingular, big-bounce cosmology from spinor-torsion coupling},
  author={Nikodem J. Popławski},
  journal={Physical Review D},
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… 

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