Ralph William Gosper Jr. (born April 26, 1943), known as Bill Gosper, is an American mathematician and programmer. Along with Richard Greenblatt, he may be considered to have founded the hacker community, and he holds a place of pride in the Lisp community.
In high school, Gosper was interested in model rockets until one of his friends was injured in a rocketry accident and contracted a fatal brain infection. Gosper enrolled in MIT in 1961, and he received his bachelor's degree in mathematics from MIT in 1965 despite becoming disaffected with the mathematics department because of their anti-computer attitude.
His contributions to computational mathematics include HAKMEM and the MIT Maclisp system. He made major contributions to Macsyma, Project MAC's computer algebra system. Gosper later worked with Symbolics and Macsyma, Inc. on commercial versions of Macsyma.
He became intensely interested in the Game of Life shortly after John Horton Conway had proposed it. Conway conjectured the existence of infinitely growing patterns, and offered a reward for an example. Gosper was the first to find such a pattern, the glider gun, and won the prize. Gosper was also the originator of the hashlife algorithm that can speed up the computation of Life patterns by many orders of magnitude.
Gosper was the first person to realize the possibilities of symbolic computation on a computer as a mathematics research tool, whereas computer methods were previously limited to purely numerical methods. In particular, this research resulted in his work on continued fraction representations of real numbers, and he developed Gosper's algorithm for finding closed form hypergeometric identities.