Patrick C. Fischer

Patrick Carl Fischer (1935 to 2011) was an American computer scientist and a noted researcher in computational complexity theory and database theory. Born in St. Louis and raised in Ann Arbor, he studied at the University of Michigan and earned a doctorate at the Massachusetts Institute of Technology in 1962 with a thesis on recursion theory. He taught at Harvard, Cornell, the University of Waterloo, Pennsylvania State University and Vanderbilt University, where he chaired the computer science department for fifteen years. His early work compared models of computation, including counter machines that obey time and space hierarchy theorems, and he helped establish theoretical computer science as a discipline separate from mathematics and electrical engineering. He founded the ACM special interest group SIGACT and the Symposium on Theory of Computing. In the 1980s he turned to database theory and the nested relational model. He was also one of the targets of the Unabomber.