How Hans Bethe Stumbled Upon Perfect Quantum Theories | Quanta Magazine

Hans Bethe's ansatz, originally developed for understanding magnetic chains, ultimately found success in other areas such as spin chains and particle interactions. It was later applied to thin sheets of ice and discovered that each sheet contained waves traveling down a line, with each molecule taking on one of six different configurations. Theorists used the Bethe ansatz to precisely calculate the chances of measuring these patterns in an experiment, demonstrating its power in understanding certain quantum systems completely.