Per-Galaxy a0 Variation: Angular Velocity-Field Complexity as Carrier of Hidden State (v18 — Programs 1-12, DM-5C Minimal Carrier Confirmed)

v18 — DM-5C complete: minimal carrier confirmed, phase frozen. Single archive (1.3 MB): analysis scripts, result JSONs, source code, documentation. Core Result (unchanged): Hidden state H drives bilateral Vf_Resid-a0_Resid coupling at r = 0.77 (LOO, p < 0.001, N = 55), replicated on N = 59 independent galaxies. 1D information ceiling: 88.5% inaccessible. Red team: 11/11 pass. DM-5C: Extra Physics or Overfitting? M3 (3 params) collapses: LOO R² = −1.055. The R² = 0.90 was overfitting. shapeAmplitude is the minimal robust carrier of H (r = 0.80, LOO 7/7, bootstrap 97.8%). outerSupport has independent information (partial r = 0.50), but N = 7 is insufficient to confirm. downstreamQuietness is downstream, not causal (partial r = −0.04 controlling for shape). Complete DM-5 Series: DM-5A (CDM triaxial: 3/5 pass), DM-5B (hiddenness paradox RESOLVED), DM-5C (minimal carrier confirmed). Model Status: DEAD: CDM smooth, MOND, Fuzzy DM. No signal: SIDM, WDM. LEADING + SUFFICIENT: CDM + complex halo shape. Phase Status: FROZEN. No new analysis until new 2D kinematic data (WALLABY, MeerKAT). Data: SPARC (Lelli, McGaugh & Schombert 2016); THINGS (Walter et al. 2008).