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arXiv · 1004.0476

Perturbative Quantum Gravity as a Double Copy of Gauge Theory

Zvi Bern·John Joseph M. Carrasco·Henrik Johansson
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Abstract

In a previous paper we observed that (classical) tree-level gauge theory amplitudes can be rearranged to display a duality between color and kinematics. Once this is imposed, gravity amplitudes are obtained using two copies of gauge-theory diagram numerators. Here we conjecture that this duality persists to all quantum loop orders and can thus be used to obtain multiloop gravity amplitudes easily from gauge-theory ones. As a nontrivial test, we show that the three-loop four-point amplitude of N = 4 super-Yang-Mills theory can be arranged into a form satisfying the duality, and by taking double copies of the diagram numerators we obtain the corresponding amplitude of N = 8 supergravity. We also remark on a non-supersymmetric two-loop test based on pure Yang-Mills theory resulting in gravity coupled to an anti-symmetric tensor and dilaton.

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Zvi Bern, John Joseph M. Carrasco, Henrik Johansson. 2010-07-30. Perturbative Quantum Gravity as a Double Copy of Gauge Theory. https://doi.org/10.1103/physrevlett.105.061602

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