One-loop unifying relations between Yang-Mills theory and the nonlinear sigma model from Berends-Giele currents

Zhenhua Guo; Xin Yan

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arXiv · 2610.25972

One-loop unifying relations between Yang-Mills theory and the nonlinear sigma model from Berends-Giele currents

Zhenhua Guo·Xin Yan

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Abstract

We study unifying relations between Yang-Mills theory and the nonlinear sigma model. We extend tree-level amplitude relations expressed through differential operators to off-shell multiparticle currents and obtain one-loop integrand relations by sewing two off-shell legs. This off-shell approach may also apply to higher-loop integrands.

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Zhenhua Guo, Xin Yan. 2026-10-19. One-loop unifying relations between Yang-Mills theory and the nonlinear sigma model from Berends-Giele currents. https://arxiv.org/abs/2610.25972

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