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arXiv · 1409.8256

Einstein-Yang-Mills Scattering Amplitudes From Scattering Equations

Freddy Cachazo·Song He·Ellis Ye Yuan
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Abstract

We present the building blocks that can be combined to produce tree-level S-matrix elements of a variety of theories with various spins mixed in arbitrary dimensions. The new formulas for the scattering of $n$ massless particles are given by integrals over the positions of $n$ points on a sphere restricted to satisfy the scattering equations. As applications, we obtain all single-trace amplitudes in Einstein--Yang--Mills (EYM) theory, and generalizations to include scalars. Also in EYM but extended by a B-field and a dilaton, we present all double-trace gluon amplitudes. The building blocks are made of Pfaffians and Parke--Taylor-like factors of subsets of particle labels.

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Freddy Cachazo, Song He, Ellis Ye Yuan. 2014-09-29. Einstein-Yang-Mills Scattering Amplitudes From Scattering Equations. https://doi.org/10.1007/jhep01(2015)121

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