The Litmus Test for Physical Theories: Solving the Observer Problem of Gravitational Influence

This paper presents a definitive and falsifiable criterion—termed <b>The Litmus Test</b>—for evaluating the completeness of any physical theory:<br><i>How does gravitational influence reach every possible observer—down to moving subatomic particles—with correct timing and directionality?</i><br>The work identifies a central blind spot in both General Relativity and Quantum Field Theory, which lack a mechanistic, observer-specific delivery model for gravitational interaction. Field-based theories presuppose omnipresent curvature or continuous influence, bypassing the need to explicitly explain delivery to localized, moving entities.<br>The <b>Computed Universe (CU) model</b> is introduced as the only framework that meets all necessary conditions by:<br>Emitting <b>causal updates</b> from masses that fan out isotropically at the speed of light.Delivering gravitational effects only upon <b>arrival</b> at the observer’s voxel, with directional precision.Supporting granular influence to subatomic scales without reliance on continuous fields or speculative carriers.<br><br>The paper defines formal <b>Litmus Criteria</b> for local propagation, isotropy, timing, and resolution, and shows how the CU model uniquely satisfies them.<br><b>Strategic implications</b> include a new foundation for gravitational measurement, quantum gravity synthesis, cosmological cutoff predictions, and causal consistency within black holes.