Heisuke Hironaka (1931) is celebrated for proving in 1964 that singularities of algebraic varieties admit resolutions in characteristic zero. This means that any projective variety can be replaced by a similar one (i.e. birationally equivalent) which has no singularities. For this theorem he won the
Fields Medal in 1970. He was for many years a professor of mathematics at Harvard but currently lives in
Japan where he is deeply respected and influential. He has been active in raising funds for causes such as mathematical education.