Arthur R. Butz (born 1933 in New York City) is an American Holocaust revisionist and an associate professor of electrical engineering at Northwestern University, where has been tenured since 1974. Butz attended the Massachusetts Institute of Technology from which he received both his Bachelor of Science and, in 1956, his Master of Science degrees. In 1965 he received his Ph.D. from the University of Minnesota. His doctoral dissertation considered a problem in control engineering.
In 1976, Butz wrote The Hoax of the Twentieth Century: The Case Against the Presumed Extermination of European Jewry. The book is one of the keystones of Holocaust revisionism.
Butz attracted attention when he issued a statement in which he agreed with Iranian President Mahmoud Ahmadinejad's alleged statement that the Holocaust is a "myth." In a press release dated December 18, 2005, Butz wrote, "I congratulate him [Ahmadinejad] on becoming the first head of state to speak out clearly on these issues [the alleged fabrication of the Holocaust], and regret only that it was not a Western head of state. His political remarks receive no comment on my side. By 'political remarks' I mean those that deal with questions of what ought to happen now".
Butz invented the algorithm which bears his name and was published in 1969. A. R. Butz, Convergence with Hilbert's space filling curve, J. Comput. Sys. Sci., vol. 3, May 1969, pp 128-146. It provided a means for computing Hilbert's space-filling curve. This algorithm greatly advanced certain computer search techniques and has numerous other applications. It is used to this day. Professor Butz is the author of numerous other technical papers.