When a plate drops or a glass smashes, you’re annoyed by the mess and the cost of replacing them. But for some physicists, the broken pieces are a source of fascination: Why does everything break into such a huge variety of sizes? Now, Emmanuel Villermaux at Aix-Marseille University in France and the University Institute of France has come up with a simple, elegant law for how objects shatter, whether they are brittle solids, liquid drops, or exploding bubbles.