Space Density Theory: A Modified Gravitational Framework for Dark Matter and Galactic Dynamics

This paper proposes that space is not a passive vacuum but an active medium with a conserved, variable physical property: density. A thermodynamic-style conservation law is applied to space density, and a modified gravitational force law is derived. The framework offers a particle-free candidate explanation for the galactic rotation curve anomaly currently attributed to dark matter, makes specific testable predictions distinguishable from the standard model, and provides a new physical interpretation of the event horizon consistent with general relativity. No new particles are introduced.