COS45 — Coherence Core (Final) A Minimal Closed Axiom Set for Observable Decision Boundaries

This document defines the minimal closed axiom set of COS45. Three observable quantities are defined:δₙ(W): spectral distance to rank-n structureτ_W: indistinguishability threshold (observable quantile)ηₙ(W): admissibility margin The DECISION layer is closed:ηₙ = δₙ − τ_W No model, no training, no distributional assumption. NON-CONCLUSIVE is a valid outcome. The EXACT layer is optional and only partially connected (n=1). All results are local and protocol-dependent. This document is self-contained and defines the core of the COS45 framework.