Hidden conformal symmetry in tree-level graviton scattering

  • Florian Loebbert
  • Matin Mojaza
  • Jan Plefka
Open Access
Regular Article - Theoretical Physics


We argue that the scattering of gravitons in ordinary Einstein gravity possesses a hidden conformal symmetry at tree level in any number of dimensions. The presence of this conformal symmetry is indicated by the dilaton soft theorem in string theory, and it is reminiscent of the conformal invariance of gluon tree-level amplitudes in four dimensions. To motivate the underlying prescription, we demonstrate that formulating the conformal symmetry of gluon amplitudes in terms of momenta and polarization vectors requires manifest reversal and cyclic symmetry. Similarly, our formulation of the conformal symmetry of graviton amplitudes relies on a manifestly permutation symmetric form of the amplitude function.


Conformal and W Symmetry Scattering Amplitudes 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Institut für Physik and IRIS Adlershof, Humboldt-Universität zu BerlinBerlinGermany
  2. 2.Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-InstitutPotsdamGermany

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