Emergence of Classical Solidity: Inertial Persistence as a Phase Transition Against

We propose a unified theoretical framework explaining the emergence of macroscopic soliditythrough competition between energy scales. Introducing the Persistence Ratio PT = Ec/ℏΓ, wedemonstrate that the quantum-to-classical transition occurs when the system’s characteristic energydominates environmental decoherence rates. Explicit calculations for electrons and protons underthe cosmic microwave background (CMB) yield P(e)T ≈ 9.5×1031 and P(p)T ≈ 5.9×1063, explainingtheir classical stability. Newton’s laws emerge as the asymptotic limit of systems with high inertialpersistence, providing a quantitative criterion for classicality beyond mere decoherence.