Daniel Jay Rudolph (1949–2010) was a mathematician who was considered a leader in ergodic theory and dynamical systems.

He attended Fort Collins High School where he was active in the chemistry, physics, computer and flying clubs, and was on the student council.

[5][3] He was awarded a Master of Science in 1973[1] and completed his PhD under the supervision of Don Ornstein in 1975, with the thesis "Non-Bernoulli Behavior of the Roots of K-automorphisms".

At Maryland, he lived at "Ergodic House" with Bruce Kitchens, Brian Marcus and Laif Swanson; they were regularly visited by Doug Lind and Andres del Junco.

[5] In 1981 Rudolph was appointed associate professor at the University of Maryland[1] and was awarded a Sloan Research Fellowship.

[1] He presented several lectures, including one at the 2002 International Congress of Mathematicians in Beijing, entitled "Applications of orbit equivalence to actions of discrete amenable groups".

[1] Rudolph and his family moved to his hometown of Fort Collins in 2005, where he was appointed to the Albert C. Yates Endowed Chair in Mathematics at Colorado State University.

[5][2] He founded and directed the SPIRAL program at Maryland, an intensive six-week preparation for graduate studies in mathematical sciences.

[3][2][6] As the disease progressed, some physical activities became impossible for Rudolph, but he continued to teach and do some departmental work, including supervising PhD students.

The April 2012 volume of the journal Ergodic Theory and Dynamical Systems (Vol 32, Part 2) was dedicated to him.

One of his last papers was a joint work with Benjamin Weiss and Matthew Foreman in the journal Annals of Mathematics on the conjugacy equivalence relation of automorphisms.