Paper CCLXIV: Population-Scale Validation of the CCLVI Tilt-and-Radiate eta-Only Sector — N = 146 GWTC-4.1 + GWTC-5.0 Events Confirm rho_Pearson(Delta, chi_eff) = +0.97 with 1% Non-Spinning-Sector Accuracy

Paper CCLVI predicted that binary black-hole remnant spin is acquired through a tilt-and-radiate mechanism that produces the eta-only formula a_rem,CCLVI(eta) = 2 sqrt(3) eta (1 - 8 eta/pi^2), where the radiation efficiency 8 eta/pi^2 = 2(1-f_III) eta is fixed by Class III bulk self-coupling saturation f_III = 1 - 4/pi^2 (CCLII, CCXLIV). The framework predicts this eta-only sector factorises cleanly from the initial component-spin sector. Using the GWTC-4.1 O4a parameter-estimation release (Zenodo 10.5281/zenodo.17014085) and the GWTC-5.0 O4b release (Zenodo 10.5281/zenodo.20348005, v9), we extract LVK headline median estimates of measured remnant spin a_rem,meas and effective inspiral spin chi_eff for N = 146 events (85 O4a + 61 O4b) and compute the residual Delta = a_rem,meas - a_rem,CCLVI(eta_median). We report Pearson rho(Delta, chi_eff) = +0.9702 [95% bootstrap CI +0.9457, +0.9843], Spearman rho = +0.9639 [+0.9239, +0.9833], OLS slope +0.3716 [+0.3496, +0.3892], and OLS intercept +0.0101. The t-statistic for the Pearson correlation is ~48 on 144 dof (formally p << 10^-50). For the 63 events with |chi_eff| < 0.05, median(|Delta|) = 0.0104 and std(Delta) = 0.0153, below the typical NR-fit uncertainty floor. The slope sits within the standard NR-fitted aligned-spin contribution range (0.3-0.5), and the intercept is consistent with zero. CCLVI matches the canonical Rezzolla 2008 NR non-spinning polynomial fit to within 0.5%-1.9% across the population eta range. Two low-|chi_eff| outliers (GW230712_090405 and GW230529_181500) fall outside the |Delta| <= 0.02 NR-fit floor and point to expected refinement directions (eccentric correction and NSBH matter effects, respectively); the GW230712 outlier size depends on the eta-posterior choice (LVK precessing headline eta ~ 0.20 vs Pompili EAS eta ~ 0.227), an honest systematic the paper documents. Four explicit population-scale falsification criteria (F1-F4) are stated and all pass by wide margins. Pre-registration of CCXLV-FP1 (chi_p . M^2 residual correlation handle) on the top-10 high-|Delta| sub-population is documented for the next data release. This is the first population-scale OOB framework confirmation, executed with zero free parameters against publicly released LVK headline data. Framework count: 265 numbered papers. 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.