The hot early Universe must have lived through phase transitions around the electroweak epoch. The dynamics of this evolution is not known and is a subject of intense interest. Multi-Higgs models often possess scalar potentials which, at finite temperatures, exhibit several competing minima and may lead to phase transitions of peculiar nature. In this talk, I will show that there exists a regime in the two-Higgs-doublet model in which thermal evolution of the early Universe passes through an intermediate phase with a charge-breaking vacuum. This regime leads to a sequence of phase transitions and it can also be tested at colliders. In addition, I will show that multi-Higgs-doublet models also support phase transitions in which two neutral minima are separated by a charge-breaking bubble wall, with remarkable and yet unexplored cosmological consequences.
With support from FCT through project UIDB/00777/2020
