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arXiv · 1910.12791

Off-Shell CHY Amplitudes and Feynman Graphs

Louise Dolan·Peter Goddard
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Abstract

A polynomial form is established for the off-shell CHY scattering equations proposed by Lam and Yao. Re-expressing this in terms of independent Mandelstam invariants provides a new expression for the polynomial scattering equations, immediately valid off shell, which makes it evident that they yield the off-shell amplitudes given by massless $\phi^3$ Feynman graphs. A CHY expression for individual Feynman graphs, valid even off shell, is established through a recurrence relation.

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Louise Dolan, Peter Goddard. 2019-10-28. Off-Shell CHY Amplitudes and Feynman Graphs. https://doi.org/10.1007/jhep04(2020)141

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