Nevertheless, I want to reiterate that the chosen example of gravity-assist is just analogy for the sake of a better imagination of the physical phenomena in question. You don’t use Newton’s law of universal gravitation to calculate the electrostatic interaction between electrically charged particles, but apply the Coulomb’s law instead, which is mathematically similar to Newton’s law of universal gravitation.

In fact, the theoretical physicists are struggling without success (none have been confirmed experimentally) to reconcile the Gravitational force (large-scale structure of space-time) and the Electronuclear force (small-scale structure of elementary particles) under a single physical framework called the “Theory of Everything” (ToE).


I have no idea how you synthesized Radioactivity in your mind, but it is related to Electricity. If you are interested, please study about the Holy Grail of Electrodynamics, the “Maxwell’s equations” because Gauss’s law for electrostatics is one of the four well-known Maxwell’s equations, which can be used to derive Coulomb’s law.