Definition of Newton, Sir Isaac
- (1642–1727), English mathematician and physicist, considered the greatest single influence on theoretical physics until Einstein. In Principia Mathematica (1687), he gave a mathematical description of the laws of mechanics and gravitation and applied these to planetary motion. Opticks (1704) records his optical experiments and theories, including the discovery that white light is made up of a mixture of colors. His work in mathematics included the binomial theorem and differential calculus.