Recursion Relations, Generating Functions, and Unitarity Sums in N=4 SYM Theory
| dc.creator | Elvang, Henriette | |
| dc.creator | Freedman, Daniel Z. | |
| dc.creator | Kiermaier, Michael | |
| dc.date | 2008-08-12 | |
| dc.date | 2008-12-20 | |
| dc.date.accessioned | 2026-07-07T13:04:38Z | |
| dc.date.available | 2026-07-07T13:04:38Z | |
| dc.description | We prove that the MHV vertex expansion is valid for any NMHV tree amplitude of N=4 SYM. The proof uses induction to show that there always exists a complex deformation of three external momenta such that the amplitude falls off at least as fast as 1/z for large z. This validates the generating function for n-point NMHV tree amplitudes. We also develop generating functions for anti-MHV and anti-NMHV amplitudes. As an application, we use these generating functions to evaluate several examples of intermediate state sums on unitarity cuts of 1-, 2-, 3- and 4-loop amplitudes. In a separate analysis, we extend the recent results of arXiv:0808.0504 to prove that there exists a valid 2-line shift for any n-point tree amplitude of N=4 SYM. This implies that there is a BCFW recursion relation for any tree amplitude of the theory. | |
| dc.description | 42pp, 7 figures; v2: completion of 4-loop spin sum, typos corrected, new figure added | |
| dc.identifier | https://arxiv.org/abs/0808.1720 | |
| dc.identifier | http://arxiv.org/abs/0808.1720 | |
| dc.identifier | JHEP 0904:009,2009 | |
| dc.identifier | doi:10.1088/1126-6708/2009/04/009 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/227231 | |
| dc.subject | High Energy Physics - Theory | |
| dc.title | Recursion Relations, Generating Functions, and Unitarity Sums in N=4 SYM Theory | |
| dc.type | text |