Complex Langevin simulation of QCD at finite density and low temperature using the deformation technique
Complex Langevin simulation of QCD at finite density and low temperature using the deformation technique
复制标题
使用变形技术在有限密度和低温下进行 QCD 复杂朗之万模拟
DOI：
10.1051/epjconf/201817507017
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
J.Nishimura and S.Shimasaki
中科院分区：
文献类型：
--
作者：
K.Nagata;J.Nishimura and S.Shimasaki
本文用复朗之万方法研究了有限密度低温下的QCD。我们采用规范冷却来控制么正性模，并在Dirac算符中引入形变参数来避免奇异漂移问题。通过漂移项大小的概率分布来判断所得结果的可靠性。通过仅使用可靠的结果进行关于变形参数的外推，我们获得了原始系统的结果。我们在一个43× 8的格子上进行了模拟，结果表明，即使在重加权方法由于严重的符号问题而失败的区域，我们的方法也能很好地工作。结果，我们观察到一个延迟的重子数密度相比，相位淬火模型，这是一个明确的迹象，银火焰现象。
We study QCD at finite density and low temperature by using the complex Langevin method. We employ the gauge cooling to control the unitarity norm and intro-duce a deformation parameter in the Dirac operator to avoid the singular-drift problem. The reliability of the obtained results are judged by the probability distribution of the magnitude of the drift term. By making extrapolations with respect to the deformation parameter using only the reliable results, we obtain results for the original system. We perform simulations on a 43× 8 lattice and show that our method works well even in the region where the reweighing method fails due to the severe sign problem. As a result we observe a delayed onset of the baryon number density as compared with the phase-quenched model, which is a clear sign of the Silver Blaze phenomenon.