Anomaly and double copy in quantum self-dual Yang-Mills and gravity

Ricardo Monteiro; Ricardo Stark-Muchão; Sam Wikeley

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arXiv · 2211.12407

Anomaly and double copy in quantum self-dual Yang-Mills and gravity

Ricardo Monteiro·Ricardo Stark-Muchão·Sam Wikeley

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Abstract

Recent works have explored how scattering amplitudes in quantum self-dual Yang-Mills theory and self-dual gravity can be interpreted as resulting from an anomaly, as first proposed by W. Bardeen. We study this problem in the light-cone-gauge formulation of the theories. Firstly, we describe how the infinite tower of symmetries associated to classical integrability can be quantum corrected, exhibiting the one-loop anomaly. Secondly, we present quantum-corrected light-cone Lagrangians worthy of the simplicity of the amplitudes, building on recent works describing the anomaly in twistor space. Finally, we discover an unexpected BCJ-like double copy for the (loop-integrated) amplitudes, distinct from the well-known BCJ double copy for the loop integrands.

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Ricardo Monteiro, Ricardo Stark-Muchão, Sam Wikeley. 2022-11-22. Anomaly and double copy in quantum self-dual Yang-Mills and gravity. https://arxiv.org/abs/2211.12407

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