• DOI:10.21468/SCIPOSTPHYS.10.1.016
• Corpus ID: 202539002

Gravity loop integrands from the ultraviolet

@article{Edison2021GravityLI,
  title={Gravity loop integrands from the ultraviolet},
  author={Alex Edison and Enrico Herrmann and Julio Parra-Martinez and Jaroslav Trnka},
  journal={SciPost Physics},
  year={2021}
}

• Alex Edison, Enrico Herrmann, +1 author J. Trnka
• Published 4 September 2019
• Physics
• SciPost Physics

We demonstrate that loop integrands of
(super-)gravity scattering amplitudes possess surprising properties in the
ultraviolet (UV) region. In particular, we study the scaling of multi-particle unitarity cuts
for asymptotically large momenta and expose an improved
UV behavior of four-dimensional cuts through seven loops as compared to
standard expectations. For N=8 supergravity, we show that
the improved large momentum scaling combined with the behavior of the integrand under BCFW
deformations of external kinematics uniquely fixes the
loop integrands in a number of non-trivial cases. In the integrand
construction, all scaling conditions are homogeneous. Therefore, the only
required information about the amplitude is its vanishing at particular
points in momentum space. This homogeneous construction gives indirect
evidence for a new geometric picture for graviton amplitudes similar to the
one found for planar N=4 super Yang-Mills theory. We also show how the
behavior at infinity is related to the scaling of tree-level amplitudes under
certain multi-line chiral shifts which can be used to construct new recursion
relations.