Researchers observe inwardly rotating spirals in a nonoscillatory medium

A team of researchers at UniversitĂ© CĂ´te d’Azur and Hokkaido University have recently carried out a study exploring the spontaneous formation of spiral patterns observed on the downward-facing free surface of a horizontal liquid film. The surface examined by them entails Rayleigh-Taylor instability, which destabilizes the interface between two fluids of different densities when the heavier fluid is pushing down the lighter one.