The Interior Observer Cosmological Framework: Paper 33 - Three Languages of the Horizon: How an Event Horizon Unifies General Relativity and Quantum Mechanics

An event horizon speaks three quantum languages to the classical interior it contains — and those three languages are sufficient to derive every major cosmological observable with zero fitted parameters. The Interior Observer (IO) framework models the observable universe as the interior of a Schwarzschild black hole. Across 32 papers, it derives the CMB temperature, dark energy density, baryon fraction, three BBN abundances (χ² = 1. 13), the spectral index, the scalar amplitude, and the gravitational slip — all from one mass and one external constant. This paper reveals the organizing principle: the boundary-to-bulk crossings fall into three channels. Channel 1 (Geometric) is always on — the boundary's gauge algebra permanently imprints on bulk geometry. Channel 2 (Thermal) is state-gated — processes in thermal equilibrium with the Hawking/KMS boundary state receive geometric dressing. Channel 3 (Fermionic) is density-gated — at Planck density, boundary spinor data sources the bulk spin fluid that drives the torsion bounce, with Rₑq/Rbounce = 1. 00016 from representation theory alone. The framework closes a logical loop: Paper 1 assumed the bounce; Paper 32 derives it from the boundary's own quantum data. The premises generate the mathematics that validates the premises. No other cosmological framework derives its complete lifecycle — birth, expansion, recollapse, and rebirth — with zero continuously fitted parameters. Includes: a geometric dark-matter alternative (predicting continued null results from direct detection), a conditional no-go for quantum gravity signatures in the muon g−2, and the Holographic Selection Rule governing which observables see the boundary and which do not. Interactive bridge map: https: //dfife. github. io/bridge-map. html https: //dfife. github. io/index. html v1. 1 (April 2026): Three-channel reframe. Channel 3 (fermionic bridge, density-gated) added from Paper 32 Part VIII. Self-consistency loop section added. S₈ updated to 0. 811 (+1. 1σ). Bounce upgraded from CONDITIONAL to DERIVED/SCOPED within extended theory. Title and abstract rewritten. v1. 0 (April 2026): Publication release. Systematic inventory of all boundary-to-bulk projection crossings across Papers 1–32, organized into an atlas-level dual-channel classification (static geometric baseline and dynamic thermal channel, with mixed and architectural exceptions). Holographic Selection Rule proposed, scoped to realized typed KMS-synchronized classes, derived from the Paper 17 modular structure and rigidity package. Three-paradigm heuristic comparison (Scale Unification / Exact Duality / Channel-Gated Unification). Dark matter geometric-alternative interpretation presented with explicit proof-gap documentation. Muon g−2 conditional no-go under current bridge architecture documented (five mechanisms attempted, five killed). Adversarial review by all four AI systems completed. Master derivation catalog steps 585–600 appended to Paper 32's catalog (maintained separately on Zenodo). One external constant (γBI = 0. 2375 from LQG) shared across all papers; one irreducibly external nuclear input (QGS = 0. 068 b) imported for Li-7 (Paper 24