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arXiv · 0708.1625

On n-point Amplitudes in N=4 SYM

A. Mironov·A. Morozov·T. N. Tomaras
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Abstract

The computation of n-point planar amplitudes in N=4 SYM at strong coupling is known to be reduced to the search for solutions of the integrable 2d SO(4,2) sigma-model with growing asymptotics on the world-sheet and to the study of their Whitham deformations induced by an epsilon-regularization, which breaks both integrability and SO(4,2) symmetry. A multi-parameter (moduli) family of such solutions is constructed for n=4. They all correspond to the same s and t and some are related by SO(4,2) transformations. Nevertheless, they lead to different regularized areas, whose minimum is the Alday-Maldacena solution. A brief review of results on n-point amplitudes is also provided, with special emphasis on the underlying equivalence of the above regularized minimal area in AdS and a double contour integral along the same boundary, two purely geometric quantities.

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A. Mironov, A. Morozov, T. N. Tomaras. 2007-08-24. On n-point Amplitudes in N=4 SYM. https://doi.org/10.1088/1126-6708%2F2007%2F11%2F021

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