Baryon generation and unusual symmetry behaviour at high temperatures

Abstract

The high temperature symmetry behaviour in grand unified theories with gauge hierarchies is investigated. It is shown that in a certain range of coupling constants the electroweak symmetry is broken superstrongly at temperatures T ∼ 10 15GeV. The cosmological consequences of this phenomenon are discussed. Fermion massiveness arising from SU(2) L breaking at very early stages of Universe expansion results in the production of an acceptable baryon excess in the framework of the minimal SU(5) model with three fermion generations.