Gluons and gravitons at one loop from ambitwistor strings

  title={Gluons and gravitons at one loop from ambitwistor strings},
  author={Yvonne Geyer and Ricardo Monteiro},
  journal={Journal of High Energy Physics},
A bstractWe present new and explicit formulae for the one-loop integrands of scattering amplitudes in non-supersymmetric gauge theory and gravity, valid for any number of particles. The results exhibit the colour-kinematics duality in gauge theory and the double-copy relation to gravity, in a form that was recently observed in supersymmetric theories. The new formulae are expressed in a particular representation of the loop integrand, with only one quadratic propagator, which arises naturally… 

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