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arXiv · 1612.03885

Uniqueness from locality and BCFW shifts

Laurentiu Rodina
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Abstract

We introduce a BCFW shift which can be used to recursively build the full Yang-Mills tree-level amplitude as a function of polarization vectors. Furthermore, in line with the recent results of arXiv:1612.02797, we conjecture that the Yang-Mills tree-level scattering amplitude is uniquely fixed by locality and demanding the usual asymptotic behavior under a sufficient number of shifts. Unitarity therefore emerges from locality and constructability. We prove this statement at the leading order in the soft expansion.

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Laurentiu Rodina. 2016-12-12. Uniqueness from locality and BCFW shifts. https://doi.org/10.1007/jhep09(2019)078

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