Deriving transport equations for electroweak baryogenesis

by Kimmo KAINULAINEN (CERN-TH)

Thursday 11 Apr 2002, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

One of the most outstanding (and controversial) issues about electroweak baryogenesis concerns modelling the CP-violating out-of-equilibrium interactions of a plasma with the expanding wall fronts. I will discuss the derivation of the appropriate transport equations for fermions interacting with the wall (charge transport mechanism), in the limit of thick walls, starting from the Schwinger-Keldysh equations for the fermionic two-point function, and performing controlled expansions in gradients and in coupling constants. The most important result of the analysis is the finding that the particle phase space density function has a spectral solution to the first order in \hbar (but not beyond). This implies the validity of the semiclassical transport equations, derived via WKB-methods, or the so-called 'classical force' (CF) mechanism for EWBG. I will show in particular how the leading order CP-violating sources arising from both flow term and the collision term are consistently incorporated into the kinetic equations. Time permitting, I will also briefly summarise the status of MSSM w.r.t. baryogenesis in the CF picture.