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arXiv · 1604.03046

On-Shell Diagrams for N = 8 Supergravity Amplitudes

Paul Heslop·Arthur E. Lipstein
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Abstract

We define recursion relations for N = 8 supergravity amplitudes using a generalization of the on-shell diagrams developed for planar N = 4 super-Yang-Mills. Although the recursion relations generically give rise to non-planar on-shell diagrams, we show that at tree-level the recursion can be chosen to yield only planar diagrams, the same diagrams occurring in the planar N = 4 theory. This implies non-trivial identities for non-planar diagrams as well as interesting relations between the N = 4 and N = 8 theories. We show that the on-shell diagrams of N = 8 supergravity obey equivalence relations analogous to those of N = 4 super-Yang-Mills, and we develop a systematic algorithm for reading off Grassmannian integral formulae directly from the on-shell diagrams. We also show that the 1-loop 4-point amplitude of N = 8 supergravity can be obtained from on-shell diagrams.

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Paul Heslop, Arthur E. Lipstein. 2016-06-13. On-Shell Diagrams for N = 8 Supergravity Amplitudes. https://doi.org/10.1007/jhep06(2016)069

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