EinsteinCartanDirac gravity with U(1) symmetry breaking
Abstract
EinsteinCartan theory is an extension of the standard formulation of General Relativity where torsion (the antisymmetric part of the affine connection) is nonvanishing. Just as the spacetime metric is sourced by the stressenergy tensor of the matter fields, torsion is sourced via the spin density tensor, whose physical effects become relevant at very high spin densities. In this work we introduce an extension of the EinsteinCartanDirac theory with an electromagnetic (Maxwell) contribution minimally coupled to torsion. This contribution breaks the U(1) gauge symmetry, which is suggested by the possibility of a torsioninduced phase transition in the early Universe, yielding new physics in extreme (spin) density regimes. We obtain the generalized gravitational, electromagnetic and fermionic field equations for this theory, estimate the strength of the corrections, and discuss the corresponding phenomenology. In particular, we briefly address some astrophysical considerations regarding the relevance of the effects which might take place inside ultradense neutron stars with strong magnetic fields (magnetars).
 Publication:

European Physical Journal C
 Pub Date:
 December 2019
 DOI:
 10.1140/epjc/s1005201975363
 arXiv:
 arXiv:1902.02222
 Bibcode:
 2019EPJC...79.1023C
 Keywords:

 General Relativity and Quantum Cosmology
 EPrint:
 15 double column pages