Is electroweak baryogenesis dead?

Abstract

Electroweak baryogenesis is severely challenged in its traditional settings: the Minimal Supersymmetric Standard Model, and in more general two Higgs doublet models. Fine tuning of parameters is required, or large couplings leading to a Landau pole at scales just above the new physics introduced. The situation is somewhat better in models with a singlet scalar coupling to the Higgs so as to give a strongly first order phase transition due to a tree-level barrier, but even in this case no UV complete models had been demonstrated to give successful baryogenesis. Here we point out some directions that overcome this limitation, by introducing a new source of CP violation in the couplings of the singlet field. A model of electroweak baryogenesis requiring no fine tuning and consistent to scales far above 1 TeV is demonstrated, in which dark matter plays the leading role in creating a CP asymmetry that is the source of the baryon asymmetry.

Comments: 10 pages, 7 figures. Talk presented at Moriond Electroweak (24 Mar. 2017) and Higgs Cosmology workshop, Kavli Royal Society Centre, Chichley Hall, UK (28 Mar. 2017); v2: added discussion of bubble wall shape and velocity and references; published version