CP Violation for the Heavens and the Earth

Abstract

Electroweak baryogenesis can be driven by the top quark in a general two Higgs doublet model with extra Yukawa couplings. Higgs quartics provide the first order phase transition, while extra top Yukawa coupling ${\rho }_{tt}$ can fuel the cosmic baryon asymmetry through the ${\lambda }_t\mathrm{Im}{\rho }_{tt}$ product, with flavor-changing ${\rho }_{tc}$ coupling as backup. The impressive ACME 2018 bound on the electron electric dipole moment calls for an extra electron coupling ${\rho }_{ee}$ for exquisite cancellation among dangerous diagrams, broadening the baryogenesis solution space. The mechanism suggests that extra Yukawa couplings echo the hierarchical structure of standard Yukawa couplings. Phenomenological consequences in Higgs search and flavor physics are discussed, with $\mu$ and $\tau$ EDM touched upon.

Comments: 21 pages, 12 figures, invited review