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arXiv · 1605.04268

Scattering amplitudes from a deconstruction of Feynman diagrams

M. Maniatis·C. M. Reyes
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Abstract

We show how to apply the BCFW recursion relation to Feynman loop integrals with the help of the Feynman-tree theorem. We deconstruct in this way all Feynman diagrams in terms of on-shell subamplitudes. Every cut originating from the Feynman-tree theorem corresponds to an integration over the phase space of an unobserved particle pair. We argue that we can calculate scattering amplitudes alternatively by the construction of on-shell and gauge-invariant subamplitudes.

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M. Maniatis, C. M. Reyes. 2016-05-17. Scattering amplitudes from a deconstruction of Feynman diagrams. https://arxiv.org/abs/1605.04268

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