Speaker
Description
Electroweak baryogenesis (EWBG) provides an intriguing mechanism to explain the observed baryon asymmetry. Since a new source of CP violation is required to successfully realize this mechanism, the remarkable improvement in experimental bounds on the electric dipole moment (EDM) of electron has put models of EWBG under severe stress.I will discuss a scenario which can robustly avoid the EDM constraints. In this scenario the CP phase needed for EWBG arises predominantly from spontaneous breaking of CP, is present during the electroweak phase transition, and is relaxed to zero today. I will discuss how this scenario can be realized in Composite Higgs models and show that such models considered previously in the literature suffer from a double-tuning problem. I will then present two different classes of models that solve this double-tuning problem.
