A variance reduction technique for hadronic correlators with partially twisted boundary conditions

TL;DR

The paper introduces a new variance reduction method for lattice QCD calculations that decreases computational costs when using partially twisted boundary conditions by leveraging statistical correlations.

Contribution

A novel variance reduction technique that exploits correlations to efficiently compute hadronic correlators with multiple twist angles in lattice QCD.

Findings

Reduces computational cost for twisted boundary conditions

Effective for meson 2pt and 3pt functions

Improves momentum resolution in lattice simulations

Abstract

Partially twisted boundary conditions are widely used for improving the momentum resolution in lattice computations of hadronic correlation functions. The method is however expensive since every additional twist requires computing additional propagators. We propose a novel variance reduction technique that exploits statistical correlations to reduce the overall cost for computing correlators with additional twist angles. We explain and demonstrate the method for meson 2pt and 3pt functions.