A flat-spacetime scalar model where gravity emerges as radial ruler contraction along the line-of-sight: s = max (1 - κₑff ∫ ρ ds, 0. 01), with κₑff = 7. 39 × 10⁵ m² kg^-1 (Gaia DR3 calibrated) scaling as κₑff ∝ 1/ (1 + ρ/ρcrit) ², ρcrit = 10^-24 kg m^-3. Reproduces Milky Way rotation (220 km/s at 8 kpc → 195 km/s at 30 kpc) without dark matter, LIGO strain via density shear, redshift as λₒbs = λ₀ / s. Includes GPS clock match, proposed muonium lab test (Δf ≈ 10^-10 Hz at 1 atm), and falsifiable predictions: JWST z>5 SN extra stretch, Swarm SAA cosmic-ray spike, NANOGrav nHz background from density variance. All open—no funding.
Boris Karagiannis (Sat,) studied this question.