The External Stress–Energy Principle: A General-Relativistic Framework for Understanding Why Long-Range Fields Determine Observable Gravity A Conceptual Clarification, Not a Modified-Gravity Theory

This paper introduces a conceptual organizing principle within standard general relativity that clarifies how different components of the stress–energy tensor contribute to the external gravitational field of a body. The key result is that only long-range, externally supported stresses—such as electromagnetic rigidity—generate observable multipole structure in the curvature outside matter, while microscopic confined stresses contribute negligibly. The framework is entirely classical and remains fully consistent with Einstein’s equations. Applications are shown for atoms, solids, plasmas, and astrophysical systems.