The double copy: Bremsstrahlung and accelerating black holes
Andrés Luna (School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, Scotland, U.K.); Ricardo Monteiro (Theoretical Physics Department, CERN, Geneva, Switzerland); Isobel Nicholson (Higgs Centre for Theoretical Physics, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3JZ, Scotland, U.K.); Donal O’Connell (Higgs Centre for Theoretical Physics, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3JZ, Scotland, U.K., Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA, 93106-4030, U.S.A.); Chris White (School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, Scotland, U.K.)
Advances in our understanding of perturbation theory suggest the existence of a correspondence between classical general relativity and Yang-Mills theory. A concrete example of this correspondence, which is known as the double copy, was recently intro-duced for the case of stationary Kerr-Schild spacetimes. Building on this foundation, we examine the simple time-dependent case of an accelerating, radiating point source. The gravitational solution, which generalises the Schwarzschild solution, includes a non-trivial stress-energy tensor. This stress-energy tensor corresponds to a gauge theoretic current in the double copy. We interpret both of these sources as representing the radiative part of the field. Furthermore, in the simple example of Bremsstrahlung, we determine a scattering amplitude describing the radiation, maintaining the double copy throughout. Our results provide the strongest evidence yet that the classical double copy is directly related to the BCJ double copy for scattering amplitudes.
