The Interior Observer Cosmological Framework Paper 27 — Theorem-Grade Closures for the Scalar-Bridge Perturbation Sector

Beginning from two premises — (1) the observable universe exists inside a Schwarzschild black hole, and (2) the physics inside the horizon is the same as outside — Paper 27 executes the first fully IO-native CLASS Boltzmann code confrontation with Planck 2018 TT data. The IO-native configuration achieves 100θ_s = 1.04083 (−0.86σ from Planck) — a zero-parameter prediction of the CMB acoustic scale. The broadband TT spectrum gives χ²(TT) = 2281, a hard failure diagnosed through three rounds as an architectural mismatch: CLASS is a single-baryon bulk simulator, while the IO framework predicts three process-dependent baryon densities from boundary projection. Part II elevates six conditional premises: the Spatial CCR Lift Theorem (Theorem 27.1, DERIVED/THEOREM), the No-Doubling Theorem upgrade (Corollary 27.1a, DERIVED/THEOREM), C1a Cross-Term Vanishing (Theorem 27.2, DERIVED), AV1 Visibility-Slot Inheritance (Theorem 27.3, DERIVED/THEOREM), and corrections to C1b (A_s = 2.114 × 10⁻⁹, +0.47σ) and C3 (τ_eff = K_gauge = 0.05488, +0.12σ). Part III documents the updated conditional debt inventory. Multi-AI adversarial collaboration: Claude (Anthropic), Codex/ChatGPT (OpenAI), Gemini (Google DeepMind). https://dfife.github.io/index.html v2.0 (May 2026): Major restructure to a theorem-grade closure paper for the scalar-bridge perturbation sector. Seven new sections §§5–11 establish state-selection boundary characterization on the lifted carrier h_vec via Theorems 27.5.8, 27.6.6, 27.6.7, 27.6.15, 27.7.5, 27.8.5, 27.9.5, 27.10.7, and Corollary 27.10.8. Headline result: full state selection on h_vec remains OPEN/PREMISE_GAP but is non-damaging for current scalar predictions — residual freedom cannot act as a hidden tuning parameter. Closure boundary recorded in §11 (Theorems 27.11.1, 27.11.3–27.11.6, with Corollary 27.11.2). Theorem 27.2 (C1a) promoted to load-bearing Part I; Theorems 27.1, 27.3, Corollary 27.1a, and H2/H3 retained. Superseded v1.5 content removed (CLASS confrontation; C1b/C2c/C3 "Results Not Achieved" — covered by Paper 26 v2.0 and Paper 31). Active labels canonicalized; references list and contributors added. Reproducibility bundle: GitHub Release https://github.com/dfife/io-framework-public/releases/tag/paper27-v2.0; tarball SHA256 83bb435818e0fef0944f932a5f84f9f79457ce5f4b9c4a4777bd6b2192ee224e; mirror https://github.com/dfife/io-framework-public/tree/main/papers/paper27/v2.0. Validation: 10/10 PASS plus an independent Model Context Protocol (MCP) validation pass. Audit boundary: no active R4 = 1 use, no active independent Cosmic Microwave Background temperature prediction, and no hidden fitted parameter in the active theorem and bundle chain; retired CMB-T scripts excluded and named in the bundle audit report. Claim naming convention: https://github.com/dfife/io-framework-public/tree/main. v1.5 (April 2026): Title updated. CLASS results demoted to non-load-bearing (architectural incompatibility). C1b variance ratio KILLED as fitted parameter (IO Law); A_s = 2.114 retired, A_s = 2.007 active. Appendix replaced with Paper 26 v1.1 clean + Paper 27 theorems. Appendix purged to theorem-grade only (30+ non-theorem steps removed: scorecards, kill lists, diagnostics, literature searches, sensitivity tables). Document order corrected. Cosmetic: Schur definitive→conditional Schur, Rosetta→gauge partition, energy→matter projection. v1.4 (April 2026): Appendix Steps 58 and 60 updated to Schur definitive branch. Website added to title page. All CLASS results in Part I remain on the retired mixed branch (H₀ = 67.58) as documented in v1.1 — the mismatch diagnosis is branch-independent. v1.3 (April 2026): Paper 24 v2.0 consistency update. TBSb promoted from SEMICLASSICAL PRINCIPLE to DERIVED/SCOPED on the physical Paper 24 TT observable class via the Modular Intertwiner Theorem (Paper 24 v2.0 §13.2). Conditional debt table and Appendix C updated. v1.3 (April 2026): Paper 24 v2.0 consistency update. TBSb promoted from SEMICLASSICAL PRINCIPLE to DERIVED/SCOPED on the physical Paper 24 TT observable class via the Modular Intertwiner Theorem (Paper 24 v2.0 §13.2). Conditional debt table and Appendix C updated v1.2 (April 2026): Paper 31 consistency update. C3 (τ = K_gauge) KILLED by Paper 31 post-bridge field class no-go theorem: within the scalar primary CMB class, X_obs = f_Γ X_prim is proved impossible; only X_obs = f_Γ^{1/2} X_prim survives, giving τ = K_gauge/2. The original Paper 26 derivation τ = K_gauge/2 is restored as DERIVED/SCOPED on the reduced source-covariance class, supported by three independent routes. C1b WEAKENED: Paper 31 Weyl-response bridge (η_IO = 0.623) shows Planck’s GR lensing extraction is biased for IO geometry, removing the observational authority for the C1b correction; both A_s candidates (2.007 native, 2.114 Planck-calibrated) are now CONDITIONAL. C2c narrowed to C2q: the bridge quotient theorem shows A_s depends only on the one-dimensional bridge quotient, not the full δΓ ⊕ δK carrier. All theorem elevations in Part II (§§6-9) are unaffected. Appendix steps 417-420 added with Paper 31 cross-references. v1.1 (April 2026): Paper 29 branch consistency audit. The CLASS run in Part I (§§2–5) used the retired mixed branch (H₀ = 67.58, ω_cdm = 0.13029). The Schur definitive branch (H₀ = 68.91, Ω_m = 0.336, Ω_k = −0.006) also fails CLASS for the same architectural reason — the mismatch diagnosis is branch-independent. §2 IO-Native Parameter Set annotated. All theorem elevations (Part II §§6–10) are unaffected. v1.0 (March 2026): First fully IO-native CLASS Boltzmann code confrontation with Planck 2018 TT data: θ_s = 1.04083 (−0.86σ from Planck) with χ²(TT) = 2281, diagnosed through three rounds as an architectural mismatch between the IO boundary-projective multi-baryon framework and CLASS's single-baryon bulk simulator. Six theorem promotions: Spatial CCR Lift (Theorem 27.1), No-Doubling upgrade (Corollary 27.1a), C1a Cross-Term Vanishing (Theorem 27.2), AV1 Visibility-Slot Inheritance (Theorem 27.3), H2 Spatial CCR for WMR (via Theorem 27.1), H3 Rate is Two-Point (via Theorems 25.9–25.11). Two corrections: C1b variance ratio corrected from r=1 (−3.09σ) to r=1+γ²=Q(q_γ) (+0.47σ), SEMICLASSICAL PRINCIPLE; C3 propagator identification corrected from τ=K_gauge/2 (−3.8σ) to τ=K_gauge (+0.12σ), SEMICLASSICAL PRINCIPLE. Two elevations: C2c Hawking state selection elevated to SEMICLASSICAL PRINCIPLE via horizon-first route; H1 bridge state selection elevated to SEMICLASSICAL PRINCIPLE via minimal spatial KMS extension. Full A_s normalization chain audited: A_s = (25/9) × f_src × g_H/√2 with two semiclassical inputs (C1b, C2c), zero continuous parameters. Damped amplitude A_s e^{-2τ} preserved to 0.3% across both corrections. All seven geometric observables within 1σ of measurement. Independent AlterBBN cross-verification confirms BBN predictions at sub-percent level (Paper 24 v1.3). Items needing elevation reduced to two: PSRP and Boundary Covariance Exponent. Five-system adversarial AI collaboration.