Simon Kirwan DonaldsonBorn 20 Aug 1957.British mathematician who was awarded the Fields Medal in 1986 for his work in topology. Nearly all his work falls in the two realms of (1) differential geometry of holomorphic vector bundles and (2) applications of gauge theory to 4-manifold topology. Remarkably, Donaldson has solved problems of mathematics by using ideas from physics (wheras most mathematics in usually applied to physics). From the Yang-Mills generalizations of James Clerk Maxwell's electromagnetic equations, Donaldson used special solutions to these equations, called instantons, to look at general four-manifolds. After being awarded the Fields Medal, Donaldson continued his exploitation of ideas from physics with applications to mathematics.