Background fluctuations and Wegner corrections

Abstract

We examine the relationship between the leading amplitude of the specific heat, the first Wegner correction term, and the fluctuation-induced analytic term in a ${\phi }^4$ Landau-Ginzburg-Wilson Hamiltonian. A proposed universal relation among these quantities is shown to be incorrect. We also discuss the limit of validity for the Wegner series and its radius of convergence.