Towards thermal evolution of the most general 2HDM

Understand

We consider the scalar sector of the most general renormalizable two-Higgs-doublet model at non-zero temperature.

• We calculate the largest finite temperature corrections to the free-energy density and study thermal evolution of the ground state.
• Within the approximation chosen, we establish all possible sequences of thermal phase transitions and study their relation with the symmetries of the model.
• We show, in particular, that a charge-breaking or a CP-violating vacuum can arise at intermediate stages of thermal evolution, and that the first-order phase transition is associated with a discrete symmetry of the potential, but not of the entire scalar lagrangian.