The Sphaleron Rate: Bodeker's Leading Log

Abstract

Bodeker has recently shown that the high temperature sphaleron rate, which measures baryon number violation in the hot standard model, receives logarithmic corrections to its leading parametric behavior; Gamma = kappa' [log(m_D / g^2 T) + O(1)] (g^2 T^2 / m_D^2) \alpha_W^5 T^4. After discussing the physical origin of these corrections, I compute the leading log coefficient numerically; kappa' = 10.8 pm 0.7. The log is fairly small relative to the O(1) ``correction;'' so nonlogarithmic contributions dominate at realistic values of the coupling.

Comments: 37 pages, including 4 figures. Expansion of Appendix A discussing relation between heat bath and Langevin algorithms