Effective Free Energy of Ginzburg-Landau Model

It is argued that the presence of a nonanalytic term in the effective potential of the Ginzburg-Landau model is immaterial as far as the order of the superconductor-normal phase transition is concerned. To achieve agreement with the renormalization group, the effective potential has to be extended to include derivative terms, which provide the theory with a low momentum scale which can be varied to probe the (possible) fixed point.