STRESS–ENERGY SUBSTRATE AS A PHYSICALLY NECESSARY INTERACTION MEDIUM

This paper applies a strict mechanism-only, elimination-by-necessity analysis to the physical enforcement of energy–momentum conservation during interaction propagation. By restricting admissibility to localized exchange, reciprocal back-reaction, locality, and finite response speed, the paper examines whether abstract descriptions—particles, equations, fields as mathematical assignments, or spacetime geometry—can physically carry energy and momentum between separated interaction events. Removing all non-enforcing attributions reveals that conservation fails unless a physically real, continuous interaction medium exists. The analysis establishes by logical necessity the existence of a stress–energy interaction substrate that locally stores and transmits energy–momentum, providing the physical continuity required to enforce known interactions.