Effective scalar field theory for the electroweak phase transition

May, 1994
45 pages
Published in:
  • Nucl.Phys.B 441 (1995) 629-657
e-Print:
Report number:
  • BI-TP-94-27

Citations per year

199519961997199861223
Abstract: (Elsevier)
We investigate an effective model for the finite-temperature symmetry-restoration phase transition of the electroweak theory. It is obtained by dimensional reduction of the (3 + 1)-dimensional full theory and by subsequent integration over all static gauge degrees of freedom. The resulting theory corresponds to a 3-dimensional O(4) ferromagnet containing cubic and quartic terms of the field in its potential function. Possible nonperturbative effects of a magnetic screening mass are parametrically included in the potential. We analyse the theory using mean-field and numerical Monte Carlo (MC) simulation methods. At the value of the physical Higgs mass, m H = 37 GeV, considered in the present investigation, we find a discontinuous symmetry-restoring phase transition. We determine the critical temperature, order parameter jump, interface tension and latent heat characteristics of the transition. The Monte Carlo results indicate a somewhat weaker first-order phase transition as compared to the mean-field treatment, demonstrating that non-perturbative fluctuations of the Higgs field are relevant. This effect is especially important for the interface tension. Any observation of hard first-order transition could result only from non-perturbative effects related to the gauge degrees of freedom.
  • gauge field theory: SU(2)
  • Higgs model
  • finite temperature
  • effective action
  • dimension: 4
  • dimensional reduction
  • dimension: 3
  • lattice field theory
  • mean field approximation
  • critical phenomena