On the structure of scattering amplitudes in N=4 super Yang-Mills and N=8 supergravity
| dc.creator | Cachazo, Freddy | |
| dc.creator | Skinner, David | |
| dc.date | 2008-01-30 | |
| dc.date | 2008-02-04 | |
| dc.date.accessioned | 2026-07-07T09:18:10Z | |
| dc.date.available | 2026-07-07T09:18:10Z | |
| dc.description | Exploiting singularities in Feynman integrals to get information about scattering amplitudes has been particularly useful at one-loop in theories where no triangles or bubbles appear. At higher loops the integrals possess subtle singularities. In this paper we give these singularities a physical interpretation and show how they turn tedious computations into purely pictorial manipulations. We illustrate our methods with various examples from the computation of four-particle amplitudes in N=4 super Yang-Mills and N=8 supergravity. Along the way we find clues towards an understanding i) of the rung-rule as a consequence of infra-red singularities, ii) of the non rung-rule integrals included in the basis as corrections to the rung-rule and iii) of the coefficients - including signs - of these two types of contribution. The role of corrections is to cancel unphysical singularities generically present in rung-rule integrals. A further byproduct, coming from the fact such unphysical singularities are located where conformal cross-ratios become unity, is the possibility of understanding the dual conformal invariance ansatz for constructing the basis of four-particle amplitudes in N=4 super Yang-Mills. | |
| dc.description | 41 pages, 16 figures; references added, clarification added in section 6B | |
| dc.identifier | https://arxiv.org/abs/0801.4574 | |
| dc.identifier | http://arxiv.org/abs/0801.4574 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/153927 | |
| dc.subject | High Energy Physics - Theory | |
| dc.title | On the structure of scattering amplitudes in N=4 super Yang-Mills and N=8 supergravity | |
| dc.type | text |