Critical confluent corrections: Universality and estimates of amplitude ratios from field theory atd=3

Abstract

We estimate, at $d=3\mathrm{}$, from ${\phi }^4$ field theory the universal ratios of confluent critical correction amplitudes relative to the correlation length, the susceptibility, and the specific heat above $T_c$. Our central values are comparable to these available from analysis of high-temperature series and the $\epsilon$ expansion. Furthermore, experiments in progress on a binary mixture are in good agreement with one of our results, the ratio of the confluent corrections for the specific heat and susceptibility which have not been previously estimated. We also present, in detail, a derivation of the universality of these quantities in the framework of field theory.