Henry Abel Dye Jr. (1926–1986) was an American mathematician, specializing in operator algebras and ergodic theory.
[2][4] Dye received from Rensselaer Polytechnic Institute a bachelor's degree and in 1950 a Ph.D. from the University of Chicago.
From 1960 until his death in 1986 he was a full professor at the University of California, Los Angeles (UCLA).
[4] His first published paper, "The Radon-Nikodym theorem for finite rings of operators", contained important results which led to many advances in the theory of von Neumann algebras, for example, the non-commutative integration theory of I.E. Segal and J. Dixmier and the modular theory of von Neumann algebras.
[2]One of the most striking early results of Murray and von Neumann implied that all finite measure preserving actions of countable abelian groups give rise to isomorphic operator algebras.