Strong-coupling expansion of lattice O(N) sigma models

TL;DR

This paper advances the computation of continuum quantities in lattice O(N) sigma models using strong-coupling series, achieving precision comparable to Monte Carlo methods.

Contribution

It introduces a method combining long strong-coupling series and optimal observables to accurately determine continuum properties of O(N) sigma models.

Findings

Continuum quantities can be reliably computed from strong-coupling series.

The method achieves precision comparable to Monte Carlo simulations.

Progress is reported in two- and three-dimensional models.

Abstract

We report progress in the computation and analysis of strong-coupling series of two- and three-dimensional ${\rm O}(N)$ $\sigma$ models. We show that, through a combination of long strong-coupling series and judicious choice of observables, one can compute continuum quantities reliably and with a precision at least comparable with the best available Monte Carlo data.