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arXiv · 2312.01580

One-loop Bern-Carrasco-Johansson Numerators on Quadratic Propagators from the Worldsheet

Jin Dong·Yao-Qi Zhang·Yong Zhang
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Abstract

We introduce a novel approach for deriving one-loop Bern-Carrasco-Johansson (BCJ) numerators and reveal the worldsheet origin of the one-loop double copy. Our work shows that expanding Cachazo-He-Yuan half-integrands into generalized Parke-Taylor factors intrinsically generates BCJ numerators on quadratic propagators satisfying Jacobi identities. We validate our methodology by successfully reproducing one-loop BCJ numerators for Non-Linear Sigma Model as well as those of pure Yang-Mills theory in four dimensions with all-plus or single-minus helicities.

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Jin Dong, Yao-Qi Zhang, Yong Zhang. 2023-12-04. One-loop Bern-Carrasco-Johansson Numerators on Quadratic Propagators from the Worldsheet. https://doi.org/10.1103/physrevd.109.l101905

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