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arXiv · 0805.4832

Leading Singularities of the Two-Loop Six-Particle MHV Amplitude

Freddy Cachazo·Marcus Spradlin·Anastasia Volovich
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Abstract

We use the leading singularity technique to determine the planar six-particle two-loop MHV amplitude in N=4 super Yang-Mills in terms of a simple basis of integrals. Our result for the parity even part of the amplitude agrees with the one recently presented in arXiv:0803.1465. The parity-odd part of the amplitude is a new result. The leading singularity technique reduces the determination of the amplitude to finding the solution to a system of linear equations. The system of equations is easily found by computing residues. We present the complete system of equations which determines the whole amplitude, and solve the two-by-two blocks analytically. Larger blocks are solved numerically in order to test the ABDK/BDS iterative structure.

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Freddy Cachazo, Marcus Spradlin, Anastasia Volovich. 2009-02-05. Leading Singularities of the Two-Loop Six-Particle MHV Amplitude. https://doi.org/10.1103/physrevd.78.105022

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