Journal of High Energy Physics (Apr 2021)
Scattering of gravitons and spinning massive states from compact numerators
Abstract
Abstract We provide a new efficient diagrammatic tool, in the context of the scattering equations, for computation of covariant D-dimensional tree-level n-point amplitudes with pairs of spinning massive particles using compact exponential numerators. We discuss how this framework allows non-integer spin extensions of recurrence relations for amplitudes developed for integer spin. Our results facilitate the on-going program for generating observables in classical general relativity from on-shell tree amplitudes through the Kawai-Lewellen-Tye relations and generalized unitarity.
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