We report a quantitative match between the Klein ladder spectrum — the eigenvalues of the cyclic graph Laplacian L (C12) on W (G2) orbits, equal to 2 − √ 3, 1, 2, 3, 2 + √ 3, 4 with sum 14 = dim G2 — and the ratio of the metallicity-gradient break radius to the bar length in the five barred spiral galaxies of the Chen et al. (2023, MNRAS 519, 4801) TYPHOON sample. Using published values without refitting, the ratios are: NGC 1365: 0. 642 (target 2/3, −3. 7%) ; NGC 1566: 2. 034 (target 2, +1. 7%) ; NGC 1744: 1. 477 (target 3/2, −1. 6%) ; NGC 2835: 3. 988 (target 4, −0. 3%) ; NGC 5068: 1. 491 (target 3/2, −0. 6%). All five match a Klein-ladder ratio or its inverse to within 5%. The probability of this clustering by chance, against a log-uniform null distribution covering the observed range, is p = 2. 2 × 10−4 (≈3. 5σ Gaussian-equivalent). Independently, the Kewley et al. (2026, Nat. Astr. , NGC 1365 chemical-archaeology) three-zone fit yields four ratios matching framework predictions within 5%: inner/middle slope 3. 625 vs. (2 + √ 3) = 3. 732; inner/disk abundance jump 1. 549 vs. λ4/λ3 = 1. 5; disk/outer abundance jump 2. 089 vs. λ6/λ3 = 2; outer/inner break radius 3. 913 vs. (2 + √ 3). The combined evidence supports a structural prediction of the One-Octonion Brane-Bulk Framework: galactic dynamical features (bar length, break radii, inter-zone abundance jumps) are quantized on the same G2 brane-mode spectrum that governs the framework's particle and nuclear predictions. The strongest claim is geometric rather than chemical: bar length sets the fundamental length scale, and break radii fall at integer-Klein-ladder multiples of it. The inner-versus-outer slope ratio is not universal; that prediction is explicitly retracted. Seven falsifiable predictions, including new TYPHOON public-release galaxies and PHANGS-MUSE independent re-fitting, are registered. 1 Part of the One-Octonion Brane-Bulk Framework series. Anchor DOI: 10. 5281/zenodo. 19120873. Community: one-octonion-brane-bulk. Author: Bharathi Dasan Jagadeesan, M. D. , University of Minnesota. ORCID: 0000-0002-1143-941X.
Bharathi Jagadeesan (Tue,) studied this question.