  First order phase transitions are characterized by the nucleation and
evolution of bubbles. The dynamics of cosmological vacuum bubbles, where the
order parameter is independent of other degrees of freedom, are well known;
more realistic phase transitions in which the order parameter interacts with
the other constituents of the Universe is in its infancy. Here we present
high-resolution lattice simulations that explore the dynamics of bubble
evolution in which the order parameter is coupled to a relativistic fluid. We
use a generic, toy potential, that can mimic physics from the GUT scale to the
electroweak scale.
