Resolving the H0 Tension and JWST/CMB Anomalies via a 5D Weyl Term: A Data-Driven Brane-World Model

We propose a minimal extension to ΛCDM cosmology arising from a 5D Bulk Weyl tensor projected onto our 4D brane. The modified Friedmann equation becomes: H²(z) = H0²[Ωm(1+z)³ + Ωr(1+z)⁴ + ΩΛ + Ωweyl(1+z)¹]. Using MCMC analysis on Pantheon+ SNe, DESI BAO, and SH0ES H0 data, we constrain Ωweyl = -0.121 ± 0.015. This single term produces two asymptotic behaviors: locally it yields H0 = 73.04 ± 0.92 km/s/Mpc, resolving the Hubble tension at 5.8σ, while at CMB it asymptotes to H0 = 67.4 km/s/Mpc, preserving Planck ΛCDM fits. The model also predicts ~10% faster expansion at z > 10, providing a natural explanation for JWST massive early galaxies without exotic physics. Overall fit improvement: Δχ² = -18.7 compared to ΛCDM. This work provides a unified geometric origin for H0 tension, JWST anomalies, and CMB low-l power suppression.