论文标题
壳递归关系与多线变形的边界贡献
Boundary Contributions of On-shell Recursion Relations With Multiple-line Deformation
论文作者
论文摘要
壳上的递归关系已被公认为是计算量子场理论中树级幅度的强大工具，但是当变形振幅的残基$ \ hat {a}（z）$在$ z $的无限元中不会消失时，它的运行不佳。但是，在这种情况下，我们仍然可以通过明确计算边界贡献来获得正确的幅度。在ARXIV：0801.2385中，首先使用背景字段方法来分析不同理论中两个变形外线的振幅的边界行为。也已经推广了相同的方法来计算ARXIV中具有BCFW样变形的某些振幅的显式边界运算符：1507.00463。在本文中，我们将进一步将方法推广到多线变形的情况下，并显示如何在方法中提取边界行为（甚至边界贡献）。
On-shell recursion relation has been recognized as a powerful tool for calculating tree level amplitudes in quantum field theory, but it doesn't work well when the residue of the deformed amplitude $\hat{A}(z)$ doesn't vanish at infinity of $z$. However, in such situation, we still can get the right amplitude by computing the boundary contribution explicitly. In arXiv:0801.2385, background field method was first used to analyze the boundary behaviors of amplitudes with two deformed external lines in different theories. The same method has also been generalized to calculate the explicit boundary operators of some amplitudes with BCFW-like deformation in arXiv:1507.00463. In this paper, we will take a step further to generalize the method into the case of multiple-line deformation, and to show how the boundary behaviors (even the boundary contributions) can be extracted in the method.
