We confirm by explicit computation the conjectured all-orders iteration of planar maximally supersymmetric N=4 Yang-Mills theory in the nontrivial case of five-point two-loop amplitudes. We compute the required unitarity cuts of the integrand and evaluate the resulting integrals numerically using a Mellin--Barnes representation and the automated package of ref.~[1]. This confirmation of the iteration relation provides further evidence suggesting that N=4 gauge theory is solvable.
@article{arxiv.hep-th/0604074,
title = {Two-Loop Iteration of Five-Point N=4 Super-Yang-Mills Amplitudes},
author = {Z. Bern and M. Czakon and D. A. Kosower and R. Roiban and V. A. Smirnov},
journal= {arXiv preprint arXiv:hep-th/0604074},
year = {2008}
}