Science at most has models that at most assume that as is so with electromagnetic radiation, so is gravity. The inverse-square relationship applies to both. Some models anticipate such a article as a
https://en.wikipedia.org/wiki/Graviton|graviton analogous to a photon but although loose photons are detectable by experiment, gravitons have yet to be detected or identified as having anything to connection with known particles.
Gravitation is apparently an inherent characteristic of matter and energy so difficult to separate from matter and energy that it defies discovery.
