Validating Einstein's Principle of Equivalence in the Context of the Theory of Gravitational Relativity

Having validated local Lorentz invariance (LLI) on flat spacetime in a gravitational field of arbitrary strength in the context of the theory of gravitational relativity (TGR), and having shown that the weak equivalence principle (WEP) is valid in the context of TGR, in so far as it is valid at the classical (or Newtonian) gravitation limit in previous articles, the invariance with position on flat spacetime in every gravitational field of the non-gravitational and gravitational laws (in their usual instantaneous differential forms), are demonstrated in every gravitational field and consequently in the entire universe. This thereby validates the strong equivalence principle (SEP) in the context of TGR. Einstein's equivalence principle (EEP) that embodies LLI, WEP and SEP has thus been validated theoretically in the context of TGR in this and previous articles.