Continuum scaling in expansions effective at a large lattice spacing

TL;DR

This paper introduces a novel truncation scheme for delta expansion on the lattice, enabling continuum scaling analysis at large lattice spacings through Borel transformation, demonstrated in various lattice models.

Contribution

It presents a new truncation approach that allows continuum limit extraction from large lattice spacing expansions, validated in multiple lattice field theories.

Findings

Successful continuum scaling from large lattice spacings in anharmonic oscillators

Effective application to d=2 non-linear sigma model at large N

Demonstration with Gross-Neveu model with Wilson fermions

Abstract

A new class of truncation schemes of delta expansion on the lattice is studied. We show that the order of expansion in delta which is introduced as the dilation parameter can be taken large enough and the result gives rise to the Borel transformation with respect to the relevant variable in the lattice models. The explicit simulation of the continuum scaling from the expansion effective at large spacings is investigated in anharmonic oscillators, d=2 non-linear sigma model at large N and Gross-Neveu model with Wilson fermions.