On n-point Amplitudes in N=4 SYM

Understand

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.