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arXiv · 1203.1019

The cusp anomalous dimension at three loops and beyond

Diego Correa·Johannes Henn·Juan Maldacena·Amit Sever
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Abstract

We derive an analytic formula at three loops for the cusp anomalous dimension Gamma_cusp(phi) in N=4 super Yang-Mills. This is done by exploiting the relation of the latter to the Regge limit of massive amplitudes. We comment on the corresponding three loops quark anti-quark potential. Our result also determines a considerable part of the three-loop cusp anomalous dimension in QCD. Finally, we consider a limit in which only ladder diagrams contribute to physical observables. In that limit, a precise agreement with strong coupling is observed.

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Diego Correa, Johannes Henn, Juan Maldacena, Amit Sever. 2012-04-30. The cusp anomalous dimension at three loops and beyond. https://doi.org/10.1007/jhep05(2012)098

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