Charles William Gear

C. William Gear (Charles William "Bill" Gear; born 1 February 1935, London) is a British-American mathematician, who specializes in numerical analysis and computer science.

Gear studied at the University of Cambridge with a bachelor's degree in 1957 and an M.A. in 1960 and at the University of Illinois, Urbana-Champaign with an M.S. in 1957 and a Ph.D. in 1960 under Abraham H. Taub with thesis Singular Shock Intersections in Plane Flow. From 1960 to 1962 he worked as an engineer for IBM. From 1962 to 1990 he was a professor of computer science at the University of Illinois, Urbana-Champaign, where he was from 1985 to 1990 head of the computer science department. From 1992 to 2000 he was president of the NEC Research Institute in Princeton.

From 1966 to 1971 he was a consultant at Argonne National Laboratory.

Gear works on numerical analysis, computer graphics, and software development. He is known for the development of BDF methods (originally introduced by the chemists Charles Francis Curtiss and Joseph Oakland Hirschfelder in 1952), a multi-step method for solving stiff systems of differential equations. Gear first published on BDF methods in 1966.

Since his retirement from NEC he has collaborated with Prof. Kevrekidis at Princeton on equation-free methods.

Gear is an American citizen. He is a Fellow of the American Academy of Arts and Sciences, the IEEE and the National Academy of Engineering. In 1987 he received an honorary doctorate from the Royal Institute of Technology in Stockholm.

Selected works

• Computer Organization and Programming. McGraw Hill, 1969; 4th edition: 1985 (with emphasis on the personal computer)
• Introduction to Computer Science. Science Research Associates, Chicago 1973
• Programming in Pascal. Science Research Associates, 1983
• Numerical Initial Value Problems in Ordinary Differential Equations. Prentice Hall, 1971
• Backward Differentiation Formulas. Scholarpedia