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arXiv · 1608.05291

Color-factor symmetry and BCJ relations for QCD amplitudes

Robert W. Brown·Stephen G. Naculich
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Abstract

Tree-level $n$-point gauge-theory amplitudes with $n-2k$ gluons and $k$ pairs of (massless or massive) particles in the fundamental (or other) representation of the gauge group are invariant under a set of symmetries that act as momentum-dependent shifts on the color factors in the cubic decomposition of the amplitude. These symmetries lead to gauge-invariant constraints on the kinematic numerators. They also directly imply the BCJ relations among the Melia-basis primitive amplitudes previously obtained by Johansson and Ochirov.

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Robert W. Brown, Stephen G. Naculich. 2016-08-18. Color-factor symmetry and BCJ relations for QCD amplitudes. https://arxiv.org/abs/1608.05291

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