A novel quark-field creation operator construction for hadronic physics in lattice QCD

TL;DR

This paper introduces a new quark-field smearing algorithm in lattice QCD that allows efficient calculation of a wide range of hadron correlation functions by enabling exact computation of reduced quark propagators at manageable costs.

Contribution

The paper presents a novel low-rank smearing technique that simplifies the construction of hadronic operators and facilitates flexible, efficient correlation function calculations without additional inversions.

Findings

Efficient calculation of hadron correlation functions demonstrated.

Exact reduced quark propagator computation achieved at reasonable costs.

Method tested successfully on realistic lattice sizes with light dynamical quarks.

Abstract

A new quark-field smearing algorithm is defined which enables efficient calculations of a broad range of hadron correlation functions. The technique applies a low-rank operator to define smooth fields that are to be used in hadron creation operators. The resulting space of smooth fields is small enough that all elements of the reduced quark propagator can be computed exactly at reasonable computational cost. Correlations between arbitrary sources, including multi hadron operators can be computed a posteriori without requiring new lattice Dirac operator inversions. The method is tested on realistic lattice sizes with light dynamical quarks.