Title: The Viscous Vacuum Framework (V2.0): Unifying the Hubble Tension, GW Dispersion, and the Cosmic Microwave Background Origin

Abstract We present an extended phenomenological framework where the physical vacuum is modeled as a viscous superfluid medium with a non-trivial refractive index (n > 1). This "Viscous Vacuum" model resolves the Hubble Tension (H0 discrepancy) not as a crisis of cosmology, but as a direct measurement of wave attenuation, yielding a viscosity parameter ηwave ≈ 0.10. We provide a comprehensive analysis of four independent observational pillars: (1) The Hubble Tension implies n ≈ 1.10; (2) Fast Radio Bursts exhibit a dispersion floor consistent with this index; (3) Raw LIGO data for GW150914 reveals a ∼ 21 ms dispersion lag; (4) The Cosmic Microwave Background (CMB) temperature of 2.725 K is derived as the thermodynamic equilibrium temperature of starlight absorbed by the viscous medium, matching historical calculations by Eddington (1926) and Regener (1933) without invoking a Big Bang singularity. We also distinguish between the Wave Regime (η ≈ 0.10) and the Matter Regime (η ≈ 0.14), offering a unified solution to both cosmological and microphysical anomalies.Contains raw data analysis of GW150914 confirming 21ms dispersion lag.