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arXiv · 1511.06716

One-Loop Soft Theorems via Dual Superconformal Symmetry

Andreas Brandhuber·Edward Hughes·Bill Spence·Gabriele Travaglini
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Abstract

We study soft theorems at one loop in planar N=4 super Yang-Mills theory through finite order in the infrared regulator and to subleading order in the soft parameter δ. In particular, we derive a universal constraint from dual superconformal symmetry, which we use to bootstrap subleading log δ behaviour. Moreover, we determine the complete infrared-finite subleading soft contribution of n-point MHV amplitudes using momentum twistors. Finally, we compute the subleading log δ behaviour of one-loop NMHV ratio functions at six and seven points, finding that universality holds within but not between helicity sectors.

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Andreas Brandhuber, Edward Hughes, Bill Spence, Gabriele Travaglini. 2015-11-20. One-Loop Soft Theorems via Dual Superconformal Symmetry. https://doi.org/10.1007/jhep03(2016)084

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