Picture two materials sandwiched together. The boundary between them may appear flat, but, in reality, it is full of tiny bumps and dents. Suddenly, the materials are hit with a shockwave. If that wave hits a bump in the material interface, it slows down. If it hits a dent, it accelerates forward. T his imbalance creates fast, narrow jets of material—called the Richtmyer-Meshkov (RM) instability. ...read more read less