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arXiv · 0909.0250

Dual Superconformal Invariance, Momentum Twistors and Grassmannians

Lionel Mason·David Skinner
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Abstract

Dual superconformal invariance has recently emerged as a hidden symmetry of planar scattering amplitudes in N=4 super Yang-Mills theory. This symmetry can be made manifest by expressing amplitudes in terms of `momentum twistors', as opposed to the usual twistors that make the ordinary superconformal properties manifest. The relation between momentum twistors and on-shell momenta is algebraic, so the translation procedure does not rely on any choice of space-time signature. We show that tree amplitudes and box coefficients are succinctly generated by integration of holomorphic delta-functions in momentum twistors over cycles in a Grassmannian. This is analogous to, although distinct from, recent results obtained by Arkani-Hamed et al. in ordinary twistor space. We also make contact with Hodges' polyhedral representation of NMHV amplitudes in momentum twistor space.

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Lionel Mason, David Skinner. 2009-10-26. Dual Superconformal Invariance, Momentum Twistors and Grassmannians. https://doi.org/10.1088/1126-6708/2009/11/045

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