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arXiv · 1401.7274

On Yangian-invariant regularisation of deformed on-shell diagrams in N=4 super-Yang-Mills theory

Niklas Beisert·Johannes Broedel·Matteo Rosso
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Abstract

We investigate Yangian invariance of deformed on-shell diagrams with D=4, N=4 superconformal symmetry. We find that invariance implies a direct relationship between the deformation parameters and the permutation associated to the on-shell graph. We analyse the connection with deformations of scattering amplitudes in N=4 super-Yang-Mills theory and the possibility of using the deformation parameters as a regulator preserving Yangian invariance. A study of higher-point tree and loop graphs suggests that manifest Yangian invariance of the amplitude requires trivial deformation parameters.

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Niklas Beisert, Johannes Broedel, Matteo Rosso. 2014-01-28. On Yangian-invariant regularisation of deformed on-shell diagrams in N=4 super-Yang-Mills theory. https://doi.org/10.1088/1751-8113/47/36/365402

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