2002/12/31 by A. Rajantie
Physics and Astronomy · #hep-ph #astro-ph
paper · pdf · doi:10.1103/physrevd.68.021301
published as Phys.Rev. D68 (2003) 021301 · 5 pages, updated to match the version published in PRD (http://link.aps.org/abstract/PRD/v68/e021301) on 11 July 2003
arxiv created 2004/01/14 · arxiv updated 2009/11/30
Thermal fluctuations of the gauge field lead to monopole formation at the grand unified phase transition in the early Universe, even if the transition is merely a smooth crossover. The dependence of the produced monopole density on various parameters is qualitatively different from theories with global symmetries, and the monopoles have a positive correlation at short distances. The number density of monopoles may be suppressed if the grand unified symmetry is only restored for a short time by, for instance, nonthermal symmetry restoration after preheating.