Exploiting the hopping parameter expansion in the hybrid Monte Carlo (HMC) simulation of lattice QCD with two degenerate flavours of Wilson fermions

TL;DR

This paper introduces methods to improve lattice QCD simulations with Wilson fermions by utilizing hopping parameter expansions and UV-filtering techniques, leading to potential computational efficiency gains.

Contribution

It demonstrates how to exploit hopping parameter expansions at orders $ abla^2$ and $ abla^4$ and introduces UV-filtering with rooted polynomials for lattice QCD simulations.

Findings

Numerical tests show feasibility at specific parameters

Methods can be combined with mass preconditioning

Potential for more efficient lattice QCD simulations

Abstract

We show how the hopping parameter expansion at order $\kappa^2$ and $\kappa^4$ can be exploited in the simulation of lattice QCD with two flavours of degenerate Wilson fermions. A natural extension of this idea is a "UV-filtering" by using rooted polynomials. These approaches can be easily combined with, for example, mass preconditioning. First numerical tests are performed for the Wilson gauge action at $\beta=5.6$ and $\kappa=0.156$ and $0.1575$.