New expressions for gravitational scattering amplitudes

  title={New expressions for gravitational scattering amplitudes},
  author={Andrew P. Hodges},
  journal={Journal of High Energy Physics},
  • A. Hodges
  • Published 10 August 2011
  • Physics
  • Journal of High Energy Physics
A bstractNew methods are introduced for evaluating tree-level gravitational scattering amplitudes. A new N=7 super-symmetric recursion yields amplitudes free from the spurious double poles of the N=8 theory. This is illustrated by a new nine-term expression for the six-graviton NMHV amplitude. The general scheme also implies a simplified recurrence relation for MHV amplitudes. We show how this relation is satisfied by a new expression for MHV amplitudes, far simpler than those hitherto… 
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