Physics Seminar : CP Violation for the Heavens and the Earth




4-go-kan seminar hall and zoom


George Wei-Shu Hou (National Taiwan University)





Electroweak baryogenesis (EWBG) can be driven by the top quark in a general two Higgs doublet model (g2HDM) that has a second set of Yukawa couplings. Higgs quartic couplings can provide the needed first order phase transition, then the complex extra diagonal top Yukawa coupling ρtt can fuel the baryon asymmetry of the Universe, BAU, through the λt Imρtt product. The already impressive ACME 2018 bound on electron electric dipole moment (eEDM) was superseded in 12/2022 by JILA, and together they call for the need of a complex extra electron Yukawa coupling ρee for exquisite cancellation among dangerous diagrams. The mechanism suggests that the extra Yukawa couplings echo the hierarchical structure of the observed standard Yukawa couplings. To achieve “CP Violation for the Heavens” but evade the stringent eEDM constraint on “the Earth” is no mean feat. Phenomenological consequences in exotic Higgs search and the flavor sector are discussed, in particular, those relevant for Belle and Belle II.

Release date 2023/05/16 Updated 2024/03/12