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arXiv · 2211.00638

Perfecting one-loop BCJ numerators in SYM and supergravity

Alex Edison·Song He·Henrik Johansson·Oliver Schlotterer·Fei Teng·Yong Zhang
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Abstract

We take a major step towards computing $D$-dimensional one-loop amplitudes in general gauge theories, compatible with the principles of unitarity and the color-kinematics duality. For $n$-point amplitudes with either supersymmetry multiplets or generic non-supersymmetric matter in the loop, simple all-multiplicity expressions are obtained for the maximal cuts of kinematic numerators of $n$-gon diagrams. At $n=6,7$ points with maximal supersymmetry, we extend the cubic-diagram numerators to encode all contact terms, and thus solve the long-standing problem of \emph{simultaneously} realizing the following properties: color-kinematics duality, manifest locality, optimal power counting of loop momenta, quadratic rather than linearized Feynman propagators, compatibility with double copy as well as all graph symmetries. Color-kinematics dual representations with similar properties are presented in the half-maximally supersymmetric case at $n=4,5$ points. The resulting gauge-theory integrands and their supergravity counterparts obtained from the double copy are checked to reproduce the expected ultraviolet divergences.

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Alex Edison, Song He, Henrik Johansson, Oliver Schlotterer, Fei Teng, Yong Zhang. 2022-11-01. Perfecting one-loop BCJ numerators in SYM and supergravity. https://doi.org/10.1007/jhep02(2023)164

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