René Thom
Affiliation
From The New York Times:
“Dr. Thom's expertise was in topology, which studies the shapes and symmetries of abstract geometric objects… This passion to understand the world geometrically led him to invent catastrophe theory, which sought to quantify how continuous actions (sailing along the smooth surface of a lake) could suddenly give way to discontinuous change (plunging over a waterfall). Such events, he believed, could be described with their own topography: abstract mathematical forms, with names like the cusp, the swallowtail and the butterfly, that could be used to chart and even predict life's surprises, bringing them within reach of reason. In 1958 his work on an influential theory called cobordism, which Dr. Ruelle described as lying at the border between algebra and geometry, earned him the Fields Medal.”
Fields Medalist, 1958