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Hamiltonian lattice quantum chromodynamics at finite density with Wilson fermions

Yi-Zhong Fang·Xiang-Qian Luo
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Abstract

Quantum chromodynamics (QCD) at sufficiently high density is expected to undergo a chiral phase transition. Understanding such a transition is of particular importance for neutron star or quark star physics. In Lagrangian SU(3) lattice gauge theory, the standard approach breaks down at large chemical potential $μ$, due to the complex action problem. The Hamiltonian formulation of lattice QCD doesn't encounter such a problem. In a previous work, we developed a Hamiltonian approach at finite chemical potential $μ$ and obtained reasonable results in the strong coupling regime. In this paper, we extend the previous work to Wilson fermions. We study the chiral behavior and calculate the vacuum energy, chiral condensate and quark number density, as well as the masses of light hadrons. There is a first order chiral phase transition at zero temperature.

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Yi-Zhong Fang, Xiang-Qian Luo. 2004-03-05. Hamiltonian lattice quantum chromodynamics at finite density with Wilson fermions. https://doi.org/10.1103/physrevd.69.114501

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