Is electroweak baryogenesis dead?

Understand

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.