Critical exponents and continuum limit of the chiral transition in the U(1) Higgs model

Abstract

A careful comparison is made between results of a numerical simulation and mean-field theory for the chiral phase transition in the U(1) Higgs model with dynamical fermions. The mean-field predictions are extracted for finite lattices and non-zero bare fermion masses thus avoiding the need for extrapolations of the data. The conclusion is that the limiting continuum theory at the transition is most likely non-interacting. Results on critical exponents, their dependence on lattice size and implications for recent claims on QED are also discussed.