Horizon absorption and full scattering conversion

Evaluate horizon absorption and full scattering conversion for the separated, charge-regular Kerr–Newman gravitational and electromagnetic perturbation system, extending the established outgoing-radiation normalization to these processes.

Background

The paper develops charge-regular separated angular and radial systems for coupled gravitational and electromagnetic perturbations of Kerr–Newman spacetime, including a smooth Kerr limit. It also derives normalized maps from separated master solutions to outgoing gravitational and electromagnetic amplitudes and energy fluxes at infinity.

The analysis does not calculate horizon absorption or the complete conversion of incident gravitational and electromagnetic radiation during scattering. These quantities would require applying the boundary-normalized connection framework to fluxes at the horizon and to the full scattering problem, rather than only to outgoing radiation at infinity.