Richard Phillips Feynman (May 11, 1918 – February 15, 1988) was an American physicist known for the path integral formulation of quantum mechanics, the theory of quantum electrodynamics and the physics of the superfluidity of supercooled liquid helium, as well as work in particle physics (he proposed the parton model).

He assisted in the development of the atomic bomb and was a member of the panel that investigated the Space Shuttle Challenger disaster. In addition to his work in theoretical physics, Feynman has been credited with pioneering the field of quantum computing, and introducing the concept of nanotechnology (creation of devices at the molecular scale). He held the Richard Chace Tolman professorship in theoretical physics at Caltech.

Feynman was a keen popularizer of physics in both his books and lectures, notably a 1959 talk on top-down nanotechnology called There's Plenty of Room at the Bottom, and The Feynman Lectures on Physics.