Resolving the Hubble Tension via Kinematic Reinterpretation of the SH0ES Distance Ladder in a Void-Background Spin-2 Framework

The Hubble tension — a 5.0σ discrepancy between the locally measured H₀ = 73.04 ± 1.01 km/s/Mpc (SH0ES) and the CMB-inferred H₀ = 67.40 ± 0.50 km/s/Mpc (Planck) — is examined within SI20-4, a five-axiom void-background spin-2 framework. Axiom 1 (featureless void, no spacetime fabric) implies that cosmological redshift is interpreted as physical motion through the void rather than metric expansion. Replacing the GR recession velocity cz with the SR Doppler velocity v_Doppler = c[(1+z)²−1]/[(1+z)²+1] in the SH0ES Hubble-law analysis, while using observed luminosity distances directly from brightness measurements, yields H₀ = 68.33 ± 0.94 km/s/Mpc from 277 Pantheon+SH0ES Hubble-flow supernovae (χ²/dof = 0.696), reducing the tension with the CMB to 0.9σ with no free parameters. The result is fully reproducible from public data. Companion framework paper: SI20-4 (DOI: 10.5281/zenodo.19154843). Contact: Nigl.Research@proton.me