The Curvature Perturbation from General non-Abelian Vector Fields
Karciauskas, Mindaugas (Granada University)

We consider the generation of the primordial curvature perturbation by non-Abelian vector fields without committing to a particular group. We show that correlators of the field perturbation are anisotropic and dominated by the contribution from the classical evolution of fields. Self-interactions of non-Abelian fields make these correlators non-Gaussian too. We present a scenario in which the curvature perturbation is generated at the end of inflation by the covariant derivative term which couples Higgs fields to gauge fields. The resulting anisotropy in the power spectrum is suppressed by the number of massive vector fields after the phase transition. We show that current WMAP constraints on such anisotropy is satisfied with reasonably large gauge groups, i.e. SU(3) or SU(7) depending on the constraint. Such groups also result in the angular dependence of the power spectrum which can be detected by the Planck satellite.