MECHANISM OF THE MPEMBA EFFECT: Inertial dynamics and active nucleation

The Mpemba effect —the apparent paradox that hot water can freeze faster than cold water— is explained by three elementary physical principles operating as a continuous dynamic regime: Greater molecular agitation: The particles of hot water move with higher velocity and amplitude, increasing the frequency and intensity of collisions with the cooling medium. Induced convection: The accelerated energy transfer generates thermal gradients that trigger convection, constantly renewing the heat exchange surface and maintaining the gradient. When the gradient weakens, the residual motion of convection persists long enough to remain operative. Inertial dynamics and active nucleation: The thermal gradient sustained by convection generates organized movements within the water mass. These structural currents, which persist as residual motion even after the gradient weakens, maintain a continuous reorganization dynamic in the liquid that facilitates the formation of the first ice nuclei. The model is universal, requires no exotic mechanisms, and explains both the inconsistent replicability of the phenomenon and its dependence on initial conditions.This is the English version of the work Mecanismo del Efecto Mpemba: inercia dinámica y nucleación activa, also available in Spanish: https://doi.org/10.5281/zenodo.22133430