Shape-preserving dynamics of melting ice

We conduct tabletop experiments to discover an entire class of ice geometries that preserve their shape during melting and serve as robust attractors under perturbations. These attractors differ from predictions of the convective Stefan problem for melting. To resolve these deviations, we use our experimental data to develop and tune a phase-field model that generalizes the Stefan problem by incorporating small-scale thermodynamic effects. This work generalizes melt modeling across scales, elucidates physics at the fundamental scale of the ice-water interface, and demonstrates the striking dynamics of melting ice.