Seed perturbations for primordial magnetic fields from minimally supersymmetric standardmodel flat directions

Abstract

We demonstrate that the minimally supersymmetric standard model (MSSM)flat directions can naturally account for the seed magnetic fields in the earlyUniverse. The non-zero vacuum expectation value of an MSSM flat directioncondensate provides masses to the gauge fields and thereby breaks conformalinvariance. During inflation the condensate receives spatial perturbations andSU(2) × U(1)Y gauge currents are generated together with (hyper)magnetic fields. When theselong wavelength vector perturbations re-enter our horizon they give rise toU(1)em magnetic fields withan amplitude of 10−30 G, as required by the dynamo mechanism.