Seminarium "Teoria cząstek elementarnych i kosmologia"

Cosmological first order phase transitions are a promising source of gravitational waves, and a possible explanation of the baryon asymmetry and dark matter abundance. Predicting the phenomenological consequences of such phase transitions requires knowledge of the expansion velocity of the bubbles formed in a phase transition. In this talk, I will summarize the computation of the wall velocity and present WallGo, a software package for the computation of bubble wall velocities. WallGo is the first publicly available code that computes the matrix elements, collision integrals Boltzmann equation and scalar field equation of motion for user-defined models. I will present results obtained with WallGo, and discuss estimates of the theoretical uncertainty of the bubble wall velocity. I will end with an estimate of the wall velocity in theories with strong coupling.