Journal of Physics A Mathematical and General
Universal amplitude-exponent relations for interfaces and conformal mappings
Andrew O. Parry
Abstract
The author considers the finite-size (FS) scaling behaviour of the transverse correlation lengths xi /sub /// (n) for an interface confined in a strip geometry exactly at a second-order fluctuation-dominated wetting transition. He shows that the dimensionless amplitude ratios A/sub /// (n) = Sigma L 2 /k B T xi /sub /// (n) (with Sigma the surface stiffness coefficient) are related to the short-distance expansion critical exponent theta by A/sub /// (n) = pi 2 n(n+ theta -1)/2 for all fluctuation-dominated wetting transitions, provided the binding potential V(y) in the capillary-wave model is conformally mapped from the semi-infinite plane. He argues that the existence of this amplitude-exponent relation reflects the conformal invariance of the capillary-wave model Lagrange density and lists a number of one-point functions which can be shown to exhibit this invariance explicitly.