In functional analysis, the Hille-Yosida theorem characterizes one-parameter semigroups of linear operators on Banach spaces satisfying certain continuity restrictions. The theorem is useful for solving certain differential equations such as the heat equation. The theorem is named after the mathematicians Einar Hille and Kosaku Yosida who independently discovered the result around 1948.
Reference
- K. Yosida, Functional Analysis, Springer-Verlag 1968.