Zhijun, Li: Spatial Pressure Theory: A Gravitational Origin Mechanism Based on Uniform Background Field Perturbation

This paper formally proposes the Spatial Pressure Medium Gravitational Theory (SGT), addressing the century-old ultimate question in physics: Why does gravity exist? Based on the uniform vacuum background medium—Spatial Pressure Medium (SPM)—the theory establishes a unified, self-consistent, and falsifiable dynamical framework. For the first time, it fully reveals the deep mechanisms of gravitational origin, long-range action, gravitational waves, inertia, and the equivalence principle from the