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arXiv · 0711.0192

Some properties of the Alday-Maldacena minimum

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

The Alday-Maldacena solution, relevant to the n=4 gluon amplitude in N=4 SYM at strong coupling, was recently identified as a minimum of the regularized action in the moduli space of solutions of the AdS_5 sigma-model equations of motion. Analogous solutions of the Nambu-Goto equations for the n=4 case are presented and shown to form (modulo the reparametrization group) an equally large but different moduli space, with the Alday-Maldacena solution at the intersection of the sigma-model and Nambu-Goto moduli spaces. We comment upon the possible form of the regularized action for n=5. A function of moduli parameters z_a is written, whose minimum reproduces the BDDK one-loop five-gluon amplitude. This function may thus be considered as some kind of Legendre transform of the BDDK formula and has its own value independently of the Alday-Maldacena approach.

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A. Mironov, A. Morozov, T. Tomaras. 2007-11-01. Some properties of the Alday-Maldacena minimum. https://doi.org/10.1016/j.physletb.2007.11.025

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