Gravitational Self‐Energy and the Equivalence Principle

The equivalence principle of general relativity asserts that, locally, gravitation is completely indistinguishable from the inertial “pseudo‐force” one would experience in an appropriately contrived accelerated frame. This implies the precise equality of gravitational and inertial mass, irrespective of a body's makeup. And, from special relativity, we know that a body's inertial mass is given by its total energy in its rest frame.