Why there is something rather than nothing: Matter from weak interactions

We show how the baryon number of the universe may be created by anomalous weak interactions during a first-order weak phase transition, in both conventional two-Higgs doublet models and in the supersymmetric standard model. The process we analyze involves non-equilibrium charge transport during the phase transition. Given current estimates of anomalous baryon violation rates, the models we examine are capable of producing a baryon-to-entropy ratio as large as ρ_B/s {reversed tilde equals} 10^-6 for maximal CP violation and optimal phase transition characteristic - many orders of magnitude larger than found with previously proposed mechanisms. Thus the observed value ρ_B/s {reversed tilde equals} 10^-10 can be easily explained by weak interaction physics in a manner that may eventually be experimentally verifiable.