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arXiv · 0905.1473

Eliminating spurious poles from gauge-theoretic amplitudes

Andrew Hodges
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Abstract

This note addresses the problem of spurious poles in gauge-theoretic scattering amplitudes. New twistor coordinates for the momenta are introduced, based on the concept of dual conformal invariance. The cancellation of spurious poles for a class of NMHV amplitudes is greatly simplified in these coordinates. The poles are eliminated altogether by defining a new type of twistor integral, dual to twistor diagrams as previously studied, and considerably simpler. The geometric features indicate a supersymmetric extension of the formalism at least to all NMHV amplitudes, allowing the dihedral symmetry of the super-amplitude to be made manifest. More generally, the definition of `momentum-twistor' coordinates suggests a powerful new approach to the study of scattering amplitudes.

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Andrew Hodges. 2009-05-11. Eliminating spurious poles from gauge-theoretic amplitudes. https://arxiv.org/abs/0905.1473

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