2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/220597The general relativistic version is developed for Robertson's discussion of the Poynting-Robertson effect that he based on special relativity and Newtonian gravity for point radiation sources like stars. The general relativistic model uses a test radiation field of photons in outward radial motion with zero angular momentum in the equatorial plane of the exterior Schwarzschild or Kerr spacetime.19 pages iop style, 8 eps figure files for 5 figuresGeneral Relativity and Quantum Cosmologytext