The Hubble tension is the discrepancy between early-universe measurements of H₀ (from CMB, ~67 km/s/Mpc) and late-universe measurements (from supernovae, ~73 km/s/Mpc). This paper proposes and tests a φ-scaling ansatz: the two measurements relate by a factor of φ^(1/6). The geometric mean gives H₀ = 70.5 km/s/Mpc, consistent with Pentagon Physics predictions. The Hubble tension is not a measurement error — it is a real feature of a universe whose expansion rate is modulated by the φ-damped self-referential structure.