The Growth of Bubbles in Cosmological Phase Transitions

We study how bubbles grow after the initial nucleation event in generic first-order cosmological phase transitions characterised by the values of latent heat, interface tension and correlation length, and driven by a scalar order parameter $\phi$. Equations coupling $\phi$ and the fluid variables $v$ and $T$ and depending on a dissipative constant $\Gamma$ are derived and solved numerically in the 1+1 dimensional case starting from a slightly deformed critical bubble configuration. Parameters corresponding to QCD and electroweak phase transitions are chosen and the whole history of the bubble with formation of combustion and shock fronts is computed as a function of $\Gamma$. Both deflagrations and detonations can appear depending on the values of the parameters. Reheating due to collisions of bubbles is also computed.