https://doi.org/10.1140/epjc/s10052-015-3391-z
Regular Article - Theoretical Physics
General tree-level amplitudes by factorization limits
Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou, 310027, China
* e-mail: zkzrzm@126.com
Received:
7
December
2014
Accepted:
3
April
2015
Published online:
24
April
2015
To find boundary contributions is a rather difficult problem when applying the BCFW recursion relation. In this paper, we propose an approach to bypass this problem by calculating general tree amplitudes that contain no polynomial using factorization limits. More explicitly, we construct an expression iteratively, which produces the correct factorization limits for all physical poles, and does not contain other poles, then it should be the correct amplitude. To some extent, this approach can be considered as an alternative way to find boundary contributions. To demonstrate our approach, we present several examples: theory, pure gauge theory, Einstein–Maxwell theory, and Yukawa theory. While the amplitude allows the existence of polynomials which satisfy the correct mass dimension and helicities, this approach is not applicable to determining the full amplitude.
© SIF and Springer-Verlag Berlin Heidelberg, 2015