English

Constructing Amplitudes from Their Soft Limits

High Energy Physics - Theory 2015-05-30 v2 High Energy Physics - Phenomenology

Abstract

The existence of universal soft limits for gauge-theory and gravity amplitudes has been known for a long time. The properties of the soft limits have been exploited in numerous ways; in particular for relating an n-point amplitude to an (n-1)-point amplitude by removing a soft particle. Recently, a procedure called inverse soft was developed by which "soft" particles can be systematically added to an amplitude to construct a higher-point amplitude for generic kinematics. We review this procedure and relate it to Britto-Cachazo-Feng-Witten recursion. We show that all tree-level amplitudes in gauge theory and gravity up through seven points can be constructed in this way, as well as certain classes of NMHV gauge-theory amplitudes with any number of external legs. This provides us with a systematic procedure for constructing amplitudes solely from their soft limits.

Keywords

Cite

@article{arxiv.1108.5385,
  title  = {Constructing Amplitudes from Their Soft Limits},
  author = {Camille Boucher-Veronneau and Andrew J. Larkoski},
  journal= {arXiv preprint arXiv:1108.5385},
  year   = {2015}
}

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R2 v1 2026-06-21T18:55:47.596Z