Corrections to Universal Fluctuations in Correlated Systems: the 2D XY-model
Abstract
Generalized universality, as recently proposed, postulates a universal non-Gaussian form of the probability density function (PDF) of certain global observables for a wide class of highly correlated systems of finite volume N. Studying the 2D XY -model, we link its validity to renormalization group properties. It would be valid if there were a single dimension 0 operator, but the actual existence of several such operators leads to T-dependent corrections. The PDF is the Fourier transform of the partition function Z(q) of an auxiliary theory which differs by a dimension 0 perturbation with a very small imaginary coefficient iq/N from a theory which is asymptotically free in the infrared. We compute the PDF from a systematic loop expansion of ln Z(q).
Keywords
Cite
@article{arxiv.cond-mat/0506713,
title = {Corrections to Universal Fluctuations in Correlated Systems: the 2D XY-model},
author = {G. Mack and G. Palma and L. Vergara},
journal= {arXiv preprint arXiv:cond-mat/0506713},
year = {2009}
}
Comments
To be published in Phys. Rev. E