标题： 四味 SU(2) 晶格规范理论在非零化学势和温度下的相图 显示英文标题

标题： The Phase Diagram of Four Flavor SU(2) Lattice Gauge Theory at Nonzero Chemical Potential and Temperature

摘要： SU(2) 格点规范理论带有四个味的夸克，在非零化学势$\mu$和温度$T$下进行模拟，并将结果与有效拉格朗日量的预测进行比较。 在$16^4$格点上的模拟表明，在零$T$时，该理论经历了一个二阶相变，进入二夸克凝聚态。 多种分析方法，包括由手征微扰理论建议的状态方程拟合，表明平均场标度描述了这个临界点。 非零$T$和 $\mu$在$12^3 \times 6$格点上进行了研究。 对于较低的 $T$，增加 $\mu$ 会使系统经历二阶相变线，进入双夸克凝聚态。 在较高的 $\mu$ 下增加 $T$，系统会经历从双夸克相到夸克-胶子等离子相的一阶相变线。 一阶相变线附近发现亚稳态。 沿这一相变线存在一个三临界点，其位置与理论预测一致。 显示英文摘要

摘要： SU(2) lattice gauge theory with four flavors of quarks is simulated at nonzero chemical potential $\mu$ and temperature $T$ and the results are compared to the predictions of Effective Lagrangians. Simulations on $16^4$ lattices indicate that at zero $T$ the theory experiences a second order phase transition to a diquark condensate state. Several methods of analysis, including equation of state fits suggested by Chiral Perturbation Theory, suggest that mean-field scaling describes this critical point. Nonzero $T$ and $\mu$ are studied on $12^3 \times 6$ lattices. For low $T$, increasing $\mu$ takes the system through a line of second order phase transitions to a diquark condensed phase. Increasing $T$ at high $\mu$, the system passes through a line of first order transitions from the diquark phase to the quark-gluon plasma phase. Metastability is found in the vicinity of the first order line. There is a tricritical point along this line of transitions whose position is consistent with theoretical predictions.