Reducing Baryon Noise in Lattice QCD Through Partial Quenching

TL;DR

This paper introduces a novel partial quenching method in lattice QCD that reduces baryon noise by lowering sea quark masses, leading to significant computational efficiency improvements.

Contribution

It proposes a new partial quenching approach with sea quark masses below valence masses, improving signal-to-noise and computational efficiency in lattice QCD calculations.

Findings

Lowering sea quark masses enhances signal-to-noise ratio.

The method achieves ~10^2^(A-1) times faster computations for A nucleons.

An optimized path to the physical point in parameter space is identified.

Abstract

The study of nuclear physics using lattice QCD is hindered by an exponentially large signal-to-noise problem which is conventionally alleviated by raising the quark masses to unphysically high values. We propose a novel form of partial quenching for calculations involving nucleons in which the sea quark masses are taken to be smaller than the valence quark masses. It is shown that lowering the sea quark masses toward their physical values actually improves signal-to-noise. An optimized approach to the physical point in the (m_s, m_v) plane is proposed, with a full analysis of the cost benefit. Improvements in computing time of ~ 10^(2(A-1)), where A is the number of nucleons in the system, are shown to be possible.