Numerical Simulation of Quark-Gluon Systems with Massvely Parallel Computer QCDPAX

大规模并行计算机QCDPAX对夸克-胶子系统的数值模拟

• 批准号: 02402003
• 负责人: IWASAKI Yoichi
• 金额: $ 8.45万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02402003/
• 关键词: massively parallel computer; QCDPAX; phase transition; quark; gluon; hadron; flavor; lattice QCD; ハ-ドウエア; ソフトウエア; massively parallel computer; QCDPAX; phase transition; quark; gluon; hadron; flavor; lattice QCD; ハ-ドウエア; ソフトウエア

In order to perform a large scale computation of lattice QCD with the massively parallel computer QCDPAX, which is constructed through the Grant-in-Aid for Specially Promoted Research in 1989, the environment for the development of QCDPAX-programs is further equipped by purchasing a workstation. On this environment, a high states tics Monte Carlo simulation of the gluon system at finite temperature is performed. First, fixing the lattice size in the temporal direction to be 4, two lattices with the spatial size of 12X12X24 and 24X24X36 are simulated. With the gauge coupling constant approximately at the phase transition point, 910, 000 and 710, 000 iterations are performed respectively. Then, increasing the temporal lattice size up to 6, lattices with the spatial size of 24X24X24 and 36X36X48 are simulated with 500, 000 and 1, 200, 000 interactions respectively. The latter simulation on the 36X36X48X6 lattice improves the previous computations to a large extent both in the size of the lattice and in the number of iterations. With this simulation, we can, for example, conclude that the value of the latent heat associated with the first order deconfining phase transition is about one half of a previous estimation on a small lattice for the case of the temporal lattice size 6. Secondly, we calculated the mass of hadrons on a 24X24X24X54 lattice. With a computation with higher precision than previous simulations, we find that the phenomenological mass formula works well for the quark mass down to about 1/3 of the strange quark mass. Thidly, we studied the confinement of quarks with varying the number of flavors and find that the confinement is lost for the flavor number larger than 7 even with the infinitely large gauge coupling constant.

为了使用大规模的晶格QCD进行大规模的计算，并通过大量平行的计算机QCDPAX在1989年通过赠款构建，以专门促进研究，以购买QCDPAX-PROGRAMS的开发环境通过购买工作站进一步配备。在这种环境下，在有限温度下对Gluon系统进行高状态蒙特卡洛模拟。首先，模拟了将晶格大小固定为4，两个晶格的空间尺寸为12x12x24和24x24x36。在相转换点处的量规耦合大约在910、000和710、000迭代处进行。然后，将时间晶格尺寸提高到6，空间尺寸为24x24x24和36x36x48的晶格分别通过500、000和1、200、000相互作用模拟。后者对36x36x48x6晶格的模拟在晶格的大小和迭代次数的大小上都在很大程度上改善了先前的计算。通过此模拟，例如，我们可以得出结论，与一阶解切相过渡相关的潜热值大约是颞晶格大小6的小晶格的先前估计的一半。通过比以前的模拟更高的计算，我们发现现象学质量公式对夸克质量的效果很好地降至奇怪的夸克质量的约1/3。我们研究了夸克与风味数量不同的限制，发现即使使用无限大的量规耦合常数，大于7的风味也丢失了限制。