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arXiv · 1712.07563

The nonplanar cusp and collinear anomalous dimension at four loops in ${\mathcal N} = 4$ SYM theory

Rutger H. Boels·Tobias Huber·Gang Yang
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Abstract

We present numerical results for the nonplanar lightlike cusp and collinear anomalous dimension at four loops in ${\mathcal N} = 4$ SYM theory, which we infer from a calculation of the Sudakov form factor. The latter is expressed as a rational linear combination of uniformly transcendental integrals for arbitrary colour factor. Numerical integration in the nonplanar sector reveals explicitly the breakdown of quadratic Casimir scaling at the four-loop order. A thorough analysis of the reported numerical uncertainties is carried out.

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Rutger H. Boels, Tobias Huber, Gang Yang. 2017-12-20. The nonplanar cusp and collinear anomalous dimension at four loops in ${\mathcal N} = 4$ SYM theory. https://arxiv.org/abs/1712.07563

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