Who was a Hungarian-American mathematician, physicist, and computer scientist that helped introduce a technique for using unbounded operators to study modules generated by a single vector?
Affiliated operator In mathematics, affiliated operators were introduced by Murray and von Neumann in the theory of von Neumann algebras as a technique for using unbounded operators to study modules generated by a single vector. Later Atiyah and Singer showed that index theorems for elliptic operators on closed manifolds with infinite fundamental group could naturally be phrased in terms of unbounded operators affiliated with the von Neumann algebra of the group. Algebraic properties of affiliated operators have proved important in L cohomology, an area between analysis and geometry that evolved from the study of such index theorems.
John Harnad John Harnad (born "Hernád János", Budapest) is a Hungarian-born mathematical physicist. He did his undergraduate studies at McGill University and his doctorate at the University of Oxford (D.Phil. 1972) under the supervision of John C. Taylor. He is currently Director of the Mathematical Physics group at the Centre de recherches mathématiques (CRM), a national research centre in mathematics at the Université de Montréal and Professor in the Department of Mathematics and Statistics at Concordia University. He is an affiliate member of