Einstein's 1915 GR Coupling Matter to Gravity is not fixed at 8piG/c^4 ~ 2 x 10^-43 Newtons^-1.

We present military observational evidence that Einstein's coupling of stress-energy current densities Tuv to the gravity field Guv is a controllable variable inside matter with electromagnetic dispersion. The effective coupling in the simplest case is 8piG(erur)^2/c^4 where c^2 = (e0u0)^-1, er is the relative electric permittivity, ur is the relative magnetic permeability. A test of this hypothesis has been proposed by Dr. Michael G. Anderson of Lawrence Livermore Laboratory in a hot plasma reactor with er ~ 10^16. We also propose a much simpler cheaper modified Cavendish Experiment involving the prediction that in H20 Ice to Water phase transition, the active mass = (static er) passive mass. The equivalence principle only requires passive mass = inertial mass restricted to non-spinning neutral test particles with effective zero active mass (self-gravity). That the active mass is not equal to passive mass inside dispersive matter was first predicted by Ray Chiao as "gravitational permeativity" to obey Kramer's-Kronig retarded causality dispersion relations of analyticity of the scattering amplitudes in the upper half complex frequency plane.