ar X iv : h ep - t h / 01 09 11 8 v 1 1 4 Se p 20 01 Conformal Gaussian Approximation

We present an alternative way to determine the unknown parameter associated to a gaussian approximation in a generic twodimensional model. Instead of the standard variational approach, we propose a procedure based on a quantitative prediction of conformal invariance, valid for systems in the scaling regime, away from criticality. We illustrate our idea by considering, as an example, the sine-Gordon model. Our method gives a good approximation for the soliton mass as function of β. Pacs: 11.10.Lm 11.10.Kk ——————————– a Instituto de F́ısica La Plata, Departamento de F́ısica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata. CC 67, 1900 La Plata, Argentina. emails: [email protected], [email protected]