A Scale Dependent Structural Constant in CMB Data Predicts the Hubble Tension Through a Ripple Modification to GR Expansion

This work identifies a scale‑dependent structural constant that appears consistently across multiple CMB analysis pipelines, GCC cold‑clump sampling, lensing reconstructions, and multipole‑range decompositions. The constant forms a smooth numerical family spanning −1.75 to −1.96, with stable anchor values at −1.8889 (GCC), −1.9367 (CMB), and an asymptotic limit near −1.9593 (lensing). I show that this structural constant naturally defines the amplitude of a minimal ripple added to the standard GR expansion history. When this ripple is applied to the Hubble parameter, it produces a few‑percent shift in the inferred value of H0, matching the observed Hubble tension without introducing new physics, tuned parameters, or additional degrees of freedom. The result demonstrates that the Hubble tension emerges directly from the same geometric structure already present in CMB data. This provides a unified explanation linking CMB scale‑dependent behavior with late‑time expansion measurements. The ripple modification is small enough to preserve CMB anisotropy constraints and early‑universe observables, while large enough to reproduce the observed tension. This paper presents the ripple model, its derivation from the structural constant family, and its implications for cosmology. It is intended as a standalone preprint documenting the connection between CMB structural geometry and the Hubble tension.