 Rayleigh–Taylor instability

Rayleigh–Taylor instability is a phenomenon in fluid dynamics that occurs at the interface between two fluids of different densities when the lighter fluid is positioned above the heavier fluid. This instability can arise in various physical scenarios, such as in astrophysics, oceanography, and engineering applications. The classic example is a scenario where a heavy fluid (e.g., water) is at rest below a lighter fluid (e.g., oil).