Growth of bubbles in cosmological phase transitions.

Abstract

We study how bubbles grow after the initial nucleation event in generic first-order cosmological phase transitions characterized by the values of the latent heat $L$, interface tension $\ensuremath{\sigma}$, and correlation length $\ensuremath{\xi}$, and driven by a scalar order parameter $\ensuremath{\varphi}$. Equations coupling $\ensuremath{\varphi}(t,\mathbf{x})$ and the fluid variables $\mathbf{v}(t,\mathbf{x})$, $T(t,\mathbf{x})$ and depending on a dissipative constant $\ensuremath{\Gamma}$ are derived and solved numerically in the (1+1)-dimensional case starting from a slightly deformed critical bubble configuration $\ensuremath{\varphi}(0,\mathbf{x})$. The parameters $L$, $\ensuremath{\sigma}$, $\ensuremath{\xi}$ corresponding to QCD and electroweak phase transitions are chosen and the whole history of the bubble with the formation of combustion and shock fronts is computed as a function of $\ensuremath{\Gamma}$. Both deflagrations and detonations can appear depending on the values of the parameters. Reheating due to collisions of bubbles is also computed.