Static Superfluid–Normal Phase Interfaces in Dark-Matter Halos: Junction Conditions, Interface Location, and the Absence of Discontinuity g-Modes

This paper develops a relativistic theory of static interfaces between superfluid and normal dark matter in galactic halos. Using Israel junction conditions and thermodynamic equilibrium, it derives the interface location, analyzes its stability, predicts the absence of discontinuity g-modes under rapid phase conversion, and establishes observational consequences for galaxy rotation curves.