Gauge and gravity amplitudes on the celestial sphere

  title={Gauge and gravity amplitudes on the celestial sphere},
  author={Nikhil Kalyanapuram},
  journal={Physical Review D},
The analytic structures of scattering amplitudes in gauge theory and gravity are examined on the celestial sphere. The celestial amplitudes in the two theories---computed by employing a regulated Mellin transform---can be compared at low multiplicity. It is established by direct computation that up to five external particles, the double copy relations of Kawai, Lewellen, and Tye continue to hold identically, modulo certain multiplicative factors which are explicitly determined. Supersymmetric… 

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