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arXiv · 0707.1903

Four-Loop Collinear Anomalous Dimension in N = 4 Yang-Mills Theory

Freddy Cachazo·Marcus Spradlin·Anastasia Volovich
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Abstract

We report a calculation in N = 4 Yang-Mills of the four-loop term g^4 in the collinear anomalous dimension g(lambda) which governs the universal subleading infrared structure of gluon scattering amplitudes. Using the method of obstructions to extract this quantity from the 1/epsilon singularity in the four-gluon iterative relation at four loops, we find g^4 = -1240.9 with an estimated numerical uncertainty of 0.02%. We also analyze the implication of our result for the strong coupling behavior of g(lambda), finding support for the string theory prediction computed recently by Alday and Maldacena using AdS/CFT.

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Freddy Cachazo, Marcus Spradlin, Anastasia Volovich. 2007-11-01. Four-Loop Collinear Anomalous Dimension in N = 4 Yang-Mills Theory. https://doi.org/10.1103/physrevd.76.106004

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