Simon Bernhard Kochen (born 1934, Antwerpen) is an American mathematician, working in the fields of model theory, number theory and quantum mechanics.
Kochen received his Ph.D. (Ultrafiltered Products and Arithmetical Extensions) from Princeton University in 1958 under the direction of Alonzo Church. Since 1967 he has been a member of Princeton's Department of Mathematics. He chaired the department 1989-92 and became the Henry Burchard Fine Professor in mathematics in 1994.[1] During 1966-7 and 1978-9, Kochen was at the Institute for Advanced Study.
In 1967 he was awarded, together with James Ax, the seventh Frank Nelson Cole Prize in Number Theory for a series of three joint papers[2][3][4] on Diophantine problems from involving p-adic techniques.
In 1967 Kochen and Ernst Specker proved the Kochen–Specker theorem in quantum mechanics.[5] In 2004 Kochen and John Horton Conway proved the free will theorem. The theorem states that if we have a certain amount of free will, then, subject to certain assumptions, so must some elementary particles.