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arXiv · 1603.09731

Berends-Giele recursion for double-color-ordered amplitudes

Abstract

Tree-level double-color-ordered amplitudes are computed using Berends--Giele recursion relations applied to the bi-adjoint cubic scalar theory. The standard notion of Berends--Giele currents is generalized to double-currents and their recursions are derived from a perturbiner expansion of linearized fields that solve the non-linear field equations. Two applications are given. Firstly, we prove that the entries of the inverse KLT matrix are equal to Berends--Giele double-currents (and are therefore easy to compute). And secondly, a simple formula to generate tree-level BCJ-satisfying numerators for arbitrary multiplicity is proposed by evaluating the field-theory limit of tree-level string amplitudes for various color orderings using double-color-ordered amplitudes.

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BibTeXRIS

Carlos R. Mafra. 2016-07-27. Berends-Giele recursion for double-color-ordered amplitudes. https://doi.org/10.1007/jhep07(2016)080

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