Ellis Robert Kolchin (April 18, 1916 – October 30, 1991) was an American mathematician at Columbia University. Kolchin earned a doctorate in mathematics from Columbia University in 1941 under supervision of Joseph Ritt. He was awarded a Guggenheim Fellowship in 1954 and 1961. Kolchin worked on differential algebra and its relation to differential equations, and founded the modern theory of linear algebraic groups. His doctoral students include Azriel Rosenfeld and Irving Adler. See also Kolchin topology Lie–Kolchin theorem Picard–Vessiot theory Publications References External links 1916 births 1991 deaths 20th-century American mathematicians Columbia University alumni Columbia University faculty Institute for Advanced Study visiting scholars