THERMODYNAMICS OF THE ELECTROWEAK PHASE-TRANSITION

We discuss several general aspects of the free energy of the standard model at high temperatures. In particular the Clausius-Clapeyron equation is shown to yield a relation between the latent heat and the jump in the order parameter. The free energy is calculated as function of temperature in resummed perturbation theory to two-loop order. A new resummation procedure is proposed in which the symmetric phase and the Higgs phase are treated differently. A quantitative description of the phase transition is achieved for Higgs masses below similar to 70 GeV. The results are found to be in agreement with recent numerical simulations on large lattices. The phase transition provides no evidence for strong non-perturbative effects in the symmetric phase.