Richard Feynman

A New Yorker with a bongo-drum and a talent for explaining anything. As a young man he worked on the Manhattan Project at Los Alamos, later taught at Caltech, and became the best-loved physics teacher of the twentieth century.

In the late 1940s he developed quantum electrodynamics, the quantum theory of light and electrons, in a new form: the path integral, in which a particle takes every possible route and the results are added up. He also invented Feynman diagrams, drawings that turn terrifying calculations into bookkeeping of particles meeting and parting. He shared the 1965 Nobel Prize with Julian Schwinger and Sin-Itiro Tomonaga.

In 1981 at a conference at MIT on the physics of computation he asked how to simulate quantum systems efficiently, and argued that ordinary computers cannot do it because the cost explodes with size. His answer was to build a computer out of quantum parts. The talk was published in 1982 and is the usual starting point of quantum computing.

The path integral is the main language of modern particle physics. The 1981 talk turned quantum mechanics from a theory we describe into a resource we use. His Lectures on Physics (1963–65) are still among the best introductions to the subject.

'Shut up and calculate' is often credited to Feynman. The phrase was coined by the physicist N. David Mermin, who has said so himself; it does not appear in Feynman's writing.

The line 'What I cannot create, I do not understand' was found on Feynman's blackboard at his death in 1988. It was a note to himself, not a published statement.