Dark Matter and Baryon Asymmetry from the very Dawn of Universe

Abstract

We discuss a possibility of universally producing dark matter and baryon charge at inflation. For this purpose, we introduce a complex scalar field with the mass exceeding the Hubble rate during the last e-folds of inflation. We assume that the phase of the complex scalar is linearly coupled to the inflaton. This interaction explicitly breaking U(1)-symmetry leads to the production of a non-zero Noether charge. The latter serves as a source of dark matter abundance, or baryon asymmetry, if the complex scalar carries the baryon charge.