1203.6281 (Gang Chen)

Ward Identity implied recursion relations in Yang-Mills theory    [PDF]

Gang Chen

In gauge theory the Ward Identity constrains the behavior of the amplitude. In this letter we will study the Ward Identity for the amplitude with a pair of shifting lines with complex momenta. We find this will induce a recursion relation identical to BCFW recursion relations at the finite poles of the amplitude with complex momenta. Furthermore, according to the Ward Identity, it is also possible to transform the boundary term into a simple one, which can be obtained by a new recursion relation. For the amplitude with one off-shell line in pure Yang-Mills theory, we find this technology is feasible for obtaining the amplitude in an effective way even if there are boundary terms.

View original: http://arxiv.org/abs/1203.6281