Tricritical point of lattice QCD with Wilson quarks at finite temperature and density

TL;DR

This study investigates the phase structure of lattice QCD with Wilson fermions at finite temperature and density, revealing a tricritical point that separates different types of chiral phase transitions, which was not previously observed in similar models.

Contribution

The paper identifies a tricritical point in lattice QCD with Wilson fermions at finite T and μ, a novel finding in the Hamiltonian formalism.

Findings

Discovery of a tricritical point in the phase diagram.

Separation of first and second order chiral phase transitions.

First such tricritical point at finite T in this formalism.

Abstract

First principle study of QCD at finite temperature $T$ and chemical potential $\mu$ is essential for understanding a wide range of phenomena from heavy-ion collisions to cosmology and neutron stars. However, in the presence of finite density, the critical behavior lattice gauge theory without species doubling, is unknown. At strong coupling, we examine the phase structure on the $(\mu,T)$ plane, using Hamiltonian lattice QCD with Wilson fermions. A tricritical point is found, separating the first and second order chiral phase transitions. Such a tricritical point at finite $T$ has not been found in previous work in the Hamiltonian formalism with Kogut-Susskind fermions or naive fermions.