Symmetry nonrestoration at high temperature and the monopole problem
(Melfo, Alejandra; Dvali, Gia; Senjanovic, Goran)
Abstract

We investigate the high temperature behavior of SU(5) in its minimal version. We show that there exists a range of parameters of the Higgs potential for which the symmetry remains broken at high temperature, thus avoiding the phase transition that gives rise to the overproduction of monopoles. We also show that in such scenario the thermal production of monopoles can be suppressed in a wide range of parameters, keeping their number density below the cosmological limits.