Sphaleron transition rate at high temperature in the 1+1 D abelian Higgs model

TL;DR

This paper investigates the sphaleron transition rate at high temperatures in a 1+1 D abelian Higgs model using lattice simulations, revealing a quadratic temperature dependence and the importance of improved effective actions.

Contribution

It provides new lattice-based results for the sphaleron rate, highlighting the limitations of current classical approximations and the need for better effective actions.

Findings

Transition rate proportional to T^2 at high temperatures

Strong dependence of rate on lattice spacing a

Classical approximation requires improved effective action

Abstract

New results for the rate are presented using the canonical ensemble in the classical approximation on a spatial lattice. We find that the rate at high temperatures is proportional to $T^2$, and strongly dependent on the lattice spacing $a$. We conclude that a better effective action is needed for the classical approximation.