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Dissolving N=4 loop amplitudes into QCD tree amplitudes

Radu Roiban·Marcus Spradlin·Anastasia Volovich
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Abstract

We use the infrared consistency of one-loop amplitudes in N=4 Yang-Mills theory to derive a compact analytic formula for a tree-level NNMHV gluon scattering amplitude in QCD, the first such formula known. We argue that the IR conditions, coupled with recent advances in calculating one-loop box coefficients, can give a new tool for computing tree-level amplitudes in general. Our calculation suggests that many amplitudes have a structure which is even simpler than that revealed so far by current twistor-space constructions.

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Radu Roiban, Marcus Spradlin, Anastasia Volovich. 2004-12-27. Dissolving N=4 loop amplitudes into QCD tree amplitudes. https://doi.org/10.1103/physrevlett.94.102002

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