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arXiv · 1808.06835

Note on differential operators, CHY integrands, and unifying relations for amplitudes

Kang Zhou·Bo Feng
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Abstract

An elegant unified web for amplitudes of various theories was given by Cachazo, He and Yuan in the CHY framework a few years ago. Recently, similar web has also been constructed by Cheung, Shen and Wen, which relies on a set of differential operators. In this note, by acting these differential operators on CHY-integrands systematically, we have established the relation between these two approaches. Thus, amplitudes for all theories which have CHY representations, include gravity theory, Einstein-Yang-Mills theory, Einstein-Maxwell theory, pure Yang-Mills theory, Yang-Mills-scalar theory, Born-Infeld theory, Dirac-Born-Infeld theory and its extension, bi-adjoint scalar theory, $\phi^4$ theory, non-linear sigma model, as well as special Galileon theory, have been included in the unified web rooted from gravity theory.

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Kang Zhou, Bo Feng. 2018-08-21. Note on differential operators, CHY integrands, and unifying relations for amplitudes. https://doi.org/10.1007/jhep09(2018)160

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