Electroweak Baryogenesis with Topological Defects
  Electroweak baryogenesis has become a topic of much recent activity [1]. Here we discuss a new scenario which has the advantage of being insensitive to the order of the electroweak phase transition. We briefly review a mechanism [2] using unstable electroweak strings [3] and discuss in detail a mechanism [4] using topological defects (in particular cosmic strings) left behind after a previous phase transition. 
A.C. Davis (DAMTP, Cambridge), R. Brandenberger and M. Trodden (Brown   University)