On the wall velocity dependence of electroweak baryogenesis
  We re-evaluate the status of supersonic electroweak baryogenesis using a
generalized fluid Ansatz for the non-equilibrium distribution functions.
Instead of truncating the expansion to first order in momentum, we allow for
higher order terms as well, including up to 21 fluctuations. The collision
terms are computed analytically at leading-log accuracy. We also point out
inconsistencies in the standard treatments of transport in electroweak
baryogenesis, arguing that one cannot do without specifying an Ansatz for the
distribution function. We present the first analysis of baryogenesis using the
fluid approximation to higher orders. Our results support the recent findings
that baryogenesis may indeed be possible even in the presence of supersonic
wall velocities.
