Spinodal decomposition occurs when a binary mixture is quenched into the unstable region of its phase diagram.
The Cahn-Hilliard equation ∂φ/∂t = M∇²(φ³ − φ − κ∇²φ) drives spontaneous phase separation into A-rich and B-rich domains
that coarsen over time via Ostwald ripening, following a t^(1/3) power law.