CMBR anisotropy with primordial magnetic fields

Abstract

Galactic magnetic fields are observed of order $\ensuremath{\sim}{10}^{\ensuremath{-}6}$ G, but their origin is not definitely known yet. In this paper we consider the primordial magnetic fields generated in the early universe and analyze their effects on the density perturbations and the cosmic microwave background radiation (CMBR) anisotropy. We assume that the random magnetic fields have the power law spectrum and satisfy the force-free field condition. The peak heights of the CMBR anisotropy are shown to be shifted upward depending on the magnetic field strengths relative to the nonmagnetic field case.