Scalar and vector tail radiation from the interior of the lightcone

In a generic spacetime massless field propagates not just on the surface of forward lightcone source, but in its interior. This inside-the-lightcone "tail radiation" is often described as having "scattered" off curvature. this work, we study propagation such tail radiation for compact, static, spherically symmetric weak-field (i.e. low density) mass distribution that well line-of-sight (LOS) between source and an observer, coupled to only gravitationally. For perturbers, there are four distinct epochs observed radiation: light-cone piece; subsequent early-time tail—ending at first time signal moving speed light could travel from point perturber thence observer; middle-time tail; late-time tail, beginning last make journey. scalar vector (eg. electromagnetic radiation), revisit previously studied early perform full examination tail. Studying shorter wavelengths perturbers LOS, find carries small fraction energy received by however, total contains much more energy. We also note whereas appears observer emanate perturber—as one might expect gravitational perturbation—the come back source. speculate potential utility detecting or probing wide variety perturbations geometry including dark matter candidates halos.