In addition, we simplify the coupled-cluster expansion by using the random phase approximation (RPA) and calculate the mass of glueball state and wavefunction.The results show good scaling property.

• 另外，我们首次应用无规相（RPA）近似方法对耦合束展开过程进行简化，计算了胶球态的质量和波函数，显示出良好的标度性的结果。