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arXiv · 1009.1854

MHV Diagrams in Momentum Twistor Space

Mathew Bullimore·Lionel Mason·David Skinner
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Abstract

We show that there are remarkable simplifications when the MHV diagram formalism for N=4 super Yang-Mills is reformulated in momentum twistor space. The vertices are replaced by unity while each propagator becomes a dual superconformal `R-invariant' whose arguments may be read off from the diagram. The momentum twistor MHV rules generate a formula for the full, all-loop planar integrand of the super Yang-Mills S-matrix that is manifestly dual superconformally invariant up to the choice of a reference twistor. We give a general proof of this reformulation and illustrate its use by computing the momentum twistor NMHV and NNMHV tree amplitudes and the integrands of the MHV and NMHV 1-loop and the MHV 2-loop planar amplitudes.

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Mathew Bullimore, Lionel Mason, David Skinner. 2010-09-09. MHV Diagrams in Momentum Twistor Space. https://doi.org/10.1007/jhep12(2010)032

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