| Birth Name: | Marc Rieffel |
| Birth Date: | 22 December 1937 |
| Birth Place: | New York City, New York, United States |
| Nationality: | American |
| Fields: | C*-algebras Quantum group theory Noncommutative geometry |
| Workplaces: | University of California, Berkeley |
| Alma Mater: | Columbia University |
| Doctoral Advisor: | Richard Kadison |
| Doctoral Students: | Philip Green Jonathan Rosenberg |
| Known For: | Noncommutative torus |
Marc Aristide Rieffel is a mathematician noted for his fundamental contributions to C*-algebra[1] and quantum group theory.[2] He is currently a professor in the department of mathematics at the University of California, Berkeley.
In 2012, he was selected as one of the inaugural fellows of the American Mathematical Society.[3]
Rieffel earned his doctorate from Columbia University in 1963 under Richard Kadison with a dissertation entitled A Characterization of Commutative Group Algebras and Measure Algebras.
Rieffel introduced Morita equivalence as a fundamental notion in noncommutative geometry and as a tool for classifying C*-algebras.[1] For example, in 1981 he showed that if Aθ denotes the noncommutative torus of angle θ, then Aθ and Aη are Morita equivalent if and only if θ and η lie in the same orbit of the action of SL(2, Z) on R by fractional linear transformations.[4] More recently, Rieffel has introduced a noncommutative analogue of Gromov-Hausdorff convergence for compact metric spaces which is motivated by applications to string theory.[5]