On Conditional Regularity of 3D Navier‑Stokes: A Polycentric Geometric Framework with Scenario‑Structural Diffusion and Fluctuation Decay

The proof is based on a new geometric and categorical framework: 1. Polycentric geometry: the flow is represented as a system of interacting spheres with universal proportions. 2. Annihilation superposition: the sign of the annihilation spectrum is determined by pairwise contributions. 3. Scenario-structural diffusion: entropy-driven diffusion regularizes the flow. 4. Categorical ensemble: the ensemble is a functor from the groupoid of scenarios. 5. Correlated fluctuation decay: fluctuations decay exponentially in amplitude while preserving direction. We prove that if these five conditions hold, then the solution is globally smooth. We carefully distinguish between theorems rigorously proved, hypotheses assumed, and axioms postulated. The work does not claim to resolve the Millennium Problem unconditionally. It offers a new framework that reduces the problem to five explicit conditions, of which two are proved, two are partially proved, and one remains open.