alfred whitford (fred) lerdahl (born march 10, 1943, in madison, wisconsin) is the fritz reiner professor of musical composition at columbia university, and a composer and music theorist best known for his work on musical grammar and cognition, rhythmic theory, pitch space, and cognitive constraints on compositional systems. he has written many orchestral and chamber works, three of which were finalists for the pulitzer prize for music: "time after time" in 2001, string quartet no. 3 in 2010, and "arches" in 2011.