Equivalence Principle of Inertial and Gravitational Mass

Links: Wikipedia; Einstein (1916);  Test of EP (STEP, 2014)

According to Albert Einstein there is a strong equivalence principle between inertial and gravitational mass, which is the basis of Einstein's Theory of General Relativity. This is generally accepted.

Curently the VTOE shos that the euivalence principle is "weak", because there are experiments which can distinguish between inertial and gravitational mass.

Latest considerations lead to the conclusion that there is no equivalence between inertial and gravitational mass. This is due to the fact that the inertial mass is a pure energy effect of masses according to the definition of mass , whereas the gravitational energy is an effect on number of particles. Thus for ordinary matter there is or better there seems to be equivalence, but for elementary particles the inertial mass is different from gravitational mass.

Currently we know just the inertial masses, because these are determined by energy experiments. The gravitational masses can be estimated on basis of particle theory of VTOE. Accoring to this the inertial mass should be proportional to number of fundamental paticles of an elementary particle (except muon-neutrinos).

For example many particles like electron, positron, muons, pions  have a much higher gravitational mass than inertial mass. Difference of gravitational mass between neutrons and protons is much smaller than difference of gravitational mass.