Numerical study of QCD phase diagram at high temperature and density by a histogram method

TL;DR

This paper investigates the QCD phase diagram at high temperature and density using a histogram method combined with reweighting techniques to address the sign and overlap problems in finite density simulations.

Contribution

It introduces a histogram-based approach with reweighting to study the QCD phase structure at finite density, tackling the sign and overlap issues.

Findings

Analyzes the chemical potential dependence of probability distributions in heavy quark regions.

Examines the method's applicability to light quark regions.

Provides insights into the QCD phase transition at high temperature and density.

Abstract

We study the QCD phase structure at high temperature and density adopting a histogram method. Because the quark determinant is complex at finite density, the Monte-Carlo method cannot be applied directly. We use a reweighting method and try to solve the problems which arise in the reweighting method, i.e. the sign problem and the overlap problem. We discuss the chemical potential dependence of the probability distribution function in the heavy quark mass region and examine the applicability of the approach in the light quark region.