Classical and Quantum Two-Body Problem in General Relativity
  The two-body problem in general relativity is reduced to the problem of an effective particle (with an energy-dependent relativistic reduced mass) in an external field. The effective potential is evaluated from the Born diagram of the linearized quantum theory of gravity. It reduces to a Schwarzschild-like potential with two different `Schwarzschild radii'. The results derived in a weak field approximation are expected to be relevant for relativistic velocities. 
Amar Maheshwari, Emil Nissimov, Ivan Todorov
gr-qc hep-th