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arXiv · 2211.16405

Colour-kinematics duality, double copy, and homotopy algebras

Leron Borsten·Hyungrok Kim·Branislav Jurčo·Tommaso Macrelli·Christian Saemann·Martin Wolf
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Abstract

Colour-kinematics duality is a remarkable property of Yang-Mills theory. Its validity implies a relation between gauge theory and gravity scattering amplitudes, known as double copy. Albeit fully established at the tree level, its extension to the loop level is conjectural. Lifting the on-shell, scattering amplitudes-based description to the level of action functionals, we argue that a theory that exhibits tree-level colour-kinematics duality can be reformulated in a way such that its loop integrands manifest a generalised form of colour-kinematics duality. Moreover, we show how the structures of higher homotopy theory naturally describe this off-shell reformulation of colour-kinematics duality.

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Leron Borsten, Hyungrok Kim, Branislav Jurčo, Tommaso Macrelli, Christian Saemann, Martin Wolf. 2022-11-29. Colour-kinematics duality, double copy, and homotopy algebras. https://doi.org/10.22323/1.414.0426

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