Electroweak phase transitions in the two-Higgs-doublet model after the first LHC run

Abstract: One of the main motivations to consider beyond standard model physics is the observed matter-antimatter asymmetry of our universe, since it cannot be explained by the standard model. In this thesis we study the two-Higgs-doublet model (2HDM) in order to test if there are regions of the parameter space of this model which are not yet excluded by experiment and which can explain the asymmetry by the process  of electroweak baryogenesis. This requires a strongly first order electroweak phase transition to occur in the early evolution of the universe. In order to see if such a phase transition can be sustained by the 2HDM we study the minimum of the potential as a function of temperature by numerical methods. We find that there are non-excluded regions of parameter space of the 2HDM which can support electroweak baryogenesis.