Understanding Hadron Structure Using Lattice QCD

TL;DR

This paper discusses how lattice QCD calculations of hadron structure, including quark distributions and spin, are performed using dynamical quarks, and how these results compare with experimental data after proper extrapolation.

Contribution

It introduces a full QCD lattice approach with dynamical quarks to accurately compute hadron matrix elements and addresses previous discrepancies with experimental results.

Findings

Successful calculation of quark density and spin distributions in full QCD.

Resolution of conflicts with experimental data through chiral extrapolation.

Highlighting the computational resources needed for precise comparisons.

Abstract

Numerical evaluation of the path integral for QCD on a discrete space-time lattice has been used to calculate ground state matrix elements specifying moments of quark density and spin distributions. This talk will explain how these matrix elements have been calculated in full QCD using dynamical quarks, show how physical extrapolation to the chiral limit including the physics of the pion cloud resolves previous apparent conflicts with experiment, and describe the computational resources required for a definitive comparison with experiment.