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arXiv · 1711.08435

Tree-level gluon amplitudes on the celestial sphere

Anders Schreiber·Anastasia Volovich·Michael Zlotnikov
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Abstract

Pasterski, Shao and Strominger have recently proposed that massless scattering amplitudes can be mapped to correlators on the celestial sphere at infinity via a Mellin transform. We apply this prescription to arbitrary $n$-point tree-level gluon amplitudes. The Mellin transforms of MHV amplitudes are given by generalized hypergeometric functions on the Grassmannian $Gr(4,n)$, while generic non-MHV amplitudes are given by more complicated Gelfand $A$-hypergeometric functions.

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Anders Schreiber, Anastasia Volovich, Michael Zlotnikov. 2017-11-22. Tree-level gluon amplitudes on the celestial sphere. https://doi.org/10.1016/j.physletb.2018.04.010

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