Richard Phillips Feynman (May 11, 1918 - February 15, 1988) was an American theoretical physicist whose work helped reshape modern quantum theory. He shared the 1965 Nobel Prize in Physics for fundamental contributions to quantum electrodynamics, the theory describing how charged particles and electromagnetic radiation interact. Feynman was also an influential teacher, author and public advocate for scientific curiosity.
Born in New York City and raised in Far Rockaway, Queens, Feynman showed an early talent for mathematics and science. He studied at the Massachusetts Institute of Technology, earning his undergraduate degree in 1939, and completed his doctorate at Princeton University in 1942 under the guidance of John Archibald Wheeler. His doctoral work explored the principle of least action in quantum mechanics, an approach that later influenced his path-integral formulation of the subject.
During World War II, Feynman joined the Manhattan Project at Los Alamos, New Mexico. Working in the Theoretical Division under Hans Bethe, he contributed to calculations concerning the behavior and yield of nuclear weapons. He also helped improve the project's use of mechanical and punched-card computation. Although his wartime work was important, Feynman's later reputation rested primarily on his achievements in fundamental physics.
After the war, Feynman taught at Cornell University before joining the California Institute of Technology in 1950. At Caltech, he developed some of his most influential ideas. His path-integral formulation presented quantum behavior as a sum over possible histories, offering a powerful alternative to more conventional interpretations of quantum mechanics. He also made major contributions to the understanding of superfluidity in liquid helium and to particle physics through the parton model, which helped explain the structure of protons at high energies.
Feynman's most recognizable contribution was the creation of Feynman diagrams. These simple visual representations show how particles interact and became an essential tool for calculating processes in quantum electrodynamics and quantum field theory. Alongside Julian Schwinger and Sin-Itiro Tomonaga, he developed methods that made previously difficult calculations manageable. Their work earned them the 1965 Nobel Prize in Physics.
Feynman was equally notable for his approach to teaching. In the early 1960s, he gave a demanding series of introductory physics lectures at Caltech with Robert Leighton and Matthew Sands. The lectures were later published as The Feynman Lectures on Physics, a widely respected set of textbooks praised for its clarity, originality and physical intuition. Feynman preferred explaining the reasoning behind an idea rather than presenting formulas without context.
His interests extended beyond academic research. In a 1959 lecture, "There's Plenty of Room at the Bottom," he anticipated possibilities associated with nanotechnology and information storage. He was also an accomplished bongo player, artist and storyteller, qualities that contributed to his unusual public image.
In 1986, Feynman served on the Rogers Commission investigating the Space Shuttle Challenger disaster. His direct examination of the shuttle's solid rocket booster seals helped expose the technical and organizational failures behind the accident. He published accounts of his scientific life and public work in Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think?
Feynman's legacy combines groundbreaking research with an insistence that science should remain understandable, testable and open to questioning. His diagrams, lectures and methods continue to influence physicists and students worldwide.