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arXiv · 1811.12688

Exploring the phase diagram of finite density QCD at low temperature by the complex Langevin method

Yuta Ito·Hideo Matsufuru·Jun Nishimura·Shinji Shimasaki·Asato Tsuchiya·Shoichiro Tsutsui
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Abstract

Monte Carlo studies of QCD at finite density suffer from the sign problem, which becomes easily uncontrollable as the chemical potential $\mu$ is increased even for a moderate lattice size. In this work we make an attempt to approach the high density low temperature region by the complex Langevin method (CLM) using four-flavor staggered fermions with reasonably small quark mass on a $8^3 \times 16$ lattice. Unlike the previous work on a $4^3 \times 8$ lattice, the criterion for correct convergence is satisfied within a wide range of $\mu$ without using the deformation technique. In particular, the baryon number density exhibits a plateau behavior consistent with the formation of eight baryons, and it starts to grow gradually at some $\mu$.

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Yuta Ito, Hideo Matsufuru, Jun Nishimura, Shinji Shimasaki, Asato Tsuchiya, Shoichiro Tsutsui. 2018-11-30. Exploring the phase diagram of finite density QCD at low temperature by the complex Langevin method. https://arxiv.org/abs/1811.12688

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