Stephen Smale

From the American Mathematical Society:

"Stephen J. Smale contributed greatly, in the late 1950s and early 1960s, to the development of differential topology, a field then in its infancy. His results on immersions of spheres in Euclidean spaces still intrigue mathematicians, as witnessed by recent films and pictures on his so-called 'eversion' of the sphere. His proof of the Poincaré Conjecture for dimensions bigger or equal to 5 is one of the great mathematical achievements of the twentieth century. His h-cobordism theorem has become probably the most basic tool in differential geometry."

"Furstenberg and Smale Receive 2006–2007 Wolf Prize," AMS

Fields Medalist, 1966