A NONPERTURBATIVE MEASUREMENT OF THE BROKEN PHASE SPHALERON RATE

We develop a method to compute the sphaleron rate in the electroweak b roken phase nonperturbatively. The rate is somewhat slower than a pert urbative estimate. In SU(2) x U(1) Higgs theory at the physical value of Theta(w), and assuming that the latent heat of the phase transition reheats the universe to the equilibrium temperature, baryon number er asure after the phase transition is prevented only when (lambda/g(2))l ess than or equal to 0.036. (C) 1998 Elsevier Science B.V. All rights reserved.