Cosmic Fluctuations and Dark Matter from Scalar Field Oscillations

Abstract

Scale-invariant fluctuations and cold dark matter could originate from two different modes of a single scalar field, fluctuations from massless Goldstone oscillations and matter from massive Higgs modes. Matching the fluctuations and dark matter density observed requires a heavy scale ($\phi_0\approx 10^{16}$GeV) for the potential minimum and an extremely small self coupling ($\lambda\approx 10^{-83}$). Mode coupling causes the dark matter to form in lumps with nonnegligible velocities, leading to early collapse of dense dark matter ``miniclusters'' and halos on the scale of compact dwarf galaxies.