The Phase-State Criticality of Spacetime: Resolving the Hubble Tension via the Superfluid Manifold

This paper provides a mechanical resolution to the "Hubble Tension"—the persistent discrepancy between early-universe (Planck) and late-universe (JWST/SH0ES) measurements of the Hubble constant (H₀). While standard cosmology treats this 9\% gap as a potential crisis in physics, the Schoenfelder Model identifies it as a predictable consequence of vacuum phase dynamics. Building upon the foundations established in The Superfluid Manifold (Schoenfelder, 2026), this work introduces the "Refrigerator Effect": a process of adiabatic cooling where the vacuum manifold undergoes a phase transition as it expands. We demonstrate that: Phase-State Criticality: Spacetime undergoes a structural shift when crossing an energy-density threshold of approximately 10^24 J/m³. Refractive Discrepancy: This transition alters the manifold's refractive index (n_), creating a localized time-dilation effect. Observational Resolution: Measurements of the early universe (CMB) are filtered through a high-density "Liquid" phase manifold, while local measurements occur in a "Gaseous" phase. The "tension" is therefore not a measurement error, but a shift in the "clock speed" of the medium itself between the two eras. This manuscript serves as the cosmological proof for the Superfluid Manifold framework, bridging the gap between theoretical field density and observed expansion rates.