Proof Engine Verification: Local Cepheid-variable measurements of the Hubble constant exceed 72 km s⁻¹ Mpc⁻¹ while the 2018 Planck CMB inference yields a value below 68 km s⁻¹ Mpc⁻¹.

Automated fact-verification of the claim: "Local Cepheid-variable measurements of the Hubble constant exceed 72 km s⁻¹ Mpc⁻¹ while the 2018 Planck CMB inference yields a value below 68 km s⁻¹ Mpc⁻¹." Verdict: PROVED (with unverified citations) Key Findings The SH0ES Cepheid-calibrated distance ladder yields H₀ = 73.04 ± 1.04 km s⁻¹ Mpc⁻¹ (Riess et al. 2022), which exceeds 72 km s⁻¹ Mpc⁻¹. The Planck 2018 CMB inference under base-ΛCDM yields H₀ = 67.4 ± 0.5 km s⁻¹ Mpc⁻¹, which is below 68 km s⁻¹ Mpc⁻¹. The gap between the two measurements is 5.64 km s⁻¹ Mpc⁻¹, corresponding to the well-documented "Hubble tension" at >5σ significance. Both values are independently confirmed by cross-check sources (arXiv + IOPscience for SH0ES; arXiv + ESA portal for Planck). Files proof.py — Re-runnable Python verification script proof.md — Structured proof report proof_audit.md — Full verification audit trail proof_narrative.md — Plain-language summary proof.json — Machine-readable structured data Generated by Proof Engine v0.10.0.