Celestial amplitudes from UV to IR

@article{ArkaniHamed2020CelestialAF,
  title={Celestial amplitudes from UV to IR},
  author={Nima Arkani-Hamed and Monica Pate and Ana-Maria Raclariu and Andrew Strominger},
  journal={arXiv: High Energy Physics - Theory},
  year={2020}
}
Celestial amplitudes represent 4D scattering of particles in boost, rather than the usual energy-momentum, eigenstates and hence are sensitive to both UV and IR physics. We show that known UV and IR properties of quantum gravity translate into powerful constraints on the analytic structure of celestial amplitudes. For example the soft UV behavior of quantum gravity is shown to imply that the exact four-particle scattering amplitude is meromorphic in the complex boost weight plane with poles… 

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