Einstein–Cartan non-supersymmetric spin-polarised nucleons wall dynamos

Abstract

Einstein-Cartan (EC) gravity uses as source a spin–spin torsion contact interaction. In this paper we make use EC QCD domain walls with nucleons spins, orthogonally to the wall, as an EC chiral torsion source to investigate magnetogenesis. Dynamo amplification factor of γEU∼10−3GeV is obtained from Early universe torsion of 1 MeV. Early universe torsion and QCD topology also provide us with an estimate of magnetic helicity density of hQCD∼1034G210−3GeV. In this case, helicity in the presence of torsion is stronger than in Minkowskian spacetime. Chiral chemical potential undergoes torsion effects as well, and not only of the Hubble constant. QCD domain wall non-supersymmetric metrics [Jensen, Soleng, CQG (1998)] and Garcia de Andrade (1999), are shown to lead to exact solution of chiral dynamo equations with magnetic fields parallel to the wall due to the chiral magnetic effect (CME). A special type of Einstein-Cartan chiral dynamo solution is found on a dilatonic domain wall, where when torsion vanishes the magnetic field is constant. In this domain wall metric exponents depend only upon torsion components.