Analytic continuation in QCD-like theories at finite density and finite isospin

TL;DR

This paper investigates the effectiveness of analytic continuation in QCD-like theories without the sign problem, aiming to enhance its reliability for real QCD applications by testing interpolation methods using data from two-color QCD at finite chemical potential.

Contribution

It demonstrates improved analytic continuation techniques in sign-problem-free theories, providing insights for better predictions in real QCD.

Findings

Interpolation with suitable functions improves analytic continuation accuracy.

Results obtained in two-color QCD support the method's validity.

Enhanced predictivity of analytic continuation in QCD-like theories.

Abstract

The method of analytic continuation is one of the most powerful tools to circumvent the sign problem in lattice QCD. The present study is part of a larger project which, based on the investigation of QCD-like theories which are free of the sign problem, is aimed at testing the validity of the method of analytic continuation and at improving its predictivity, in view of its application to real QCD. We have shown that a considerable improvement can be achieved if suitable functions are used to interpolate data with imaginary chemical potential. We present results obtained in a theory free of the sign problem such as two-color QCD at finite chemical potential.