Continuum Scaling from Large Mass Expansion on the Lattice: Delta Expansion Applied to the Anharmonic Oscillator

TL;DR

This paper introduces a delta expansion method to improve the calculation of the mass gap in the lattice anharmonic oscillator, enabling better continuum limit approximations at strong coupling.

Contribution

It applies a novel delta expansion technique to lattice field theory, enhancing the accuracy of mass gap calculations in the continuum limit.

Findings

Delta expansion recovers the scaling behavior of the hopping parameter

Allows precise approximation of the mass gap at strong coupling

Improves the understanding of continuum limit in lattice models

Abstract

We dilate the scaling region of the lattice anharmonic oscillator at strong coupling by introducing the parameter delta. Performing expansion in delta, the calculation of the mass gap in the continuum limit via the series expansion effective at large lattice spacings is then studied. We show that the dilation on the mass parameter M recovers the scaling behavior of the hopping parameter beta and allows for precise approximation of the mass gap.