论文标题
彩虹改性局部近似和退化锥子
The rainbow modified-ladder approximation and degenerate pion
论文作者
论文摘要
相关函数可以通过相应的方程式描述，$ viz。$，夸克传播器的间隙方程和用于矢量穿着 - 阿贝尔 - 阿贝尔 - 统一 - 玻璃孔顶点的不均匀的伯特盐钙钙方程，其中必须实现特定的截断。一般矢量和轴向矢量病房 - 绿色takahashi身份要求将这些相关函数互连，因此，必须始终控制截断。事实证明，如果在间隙方程式中假定彩虹近似，则伯特盐盐方程中的散射内核可以采用梯子近似，这是截断散射核的最基本尝试之一。另外，还发现修改的局部近似是一种可能的对称性截断方案。为了说明用于应用的近似值，包括对亲的处理。即使伯特 - 盐分幅度具有明显的区别，也发现梯子质量和衰减常数在梯子和修饰的落水近似中是退化的。借助Gell-Mann-Oakes-Renner（GMOR）关系，检查了修改后局部近似的理由。
Correlation functions can be described by the corresponding equations, $viz.$, gap equation for quark propagator and the inhomogeneous Bethe-Salpeter equation for vector dressed-fermion-Abelian-gauge-boson vertex in which specific truncations have to be implemented. The general vector and axial-vector Ward-Green-Takahashi identities require these correlation functions to be interconnected, in consequence of this, truncations made must be controlled consistently. It turns out that if the rainbow approximation is assumed in gap equation, the scattering kernel in Bethe-Salpeter equation can adopt the ladder approximation, which is one of the most basic attempts to truncate the scattering kernel. Additionally, a modified-ladder approximation is also found to be a possible symmetry-preserving truncation scheme. As an illustration of this approximation for application a treatment of pion is included. Pion mass and decay constant are found to be degenerate in ladder and modified-ladder approximations, even though the Bethe-Salpeter amplitude are with apparent distinction. The justification for the modified-ladder approximation is examined with the help of the Gell-Mann-Oakes-Renner (GMOR) relation.
