Paul Dirac

Paul Adrien Maurice Dirac was born in Bristol, England, on August 8, 1902. His father, Charles Adrien Ladislas Dirac, a Swiss citizen born in Monthey, was a teacher of French; his mother, Florence Hannah Holten, came from Cornwall, England.⁠[1][2]

At about the age of twelve Dirac entered the secondary school run by the Merchant Venturers’ Technical College in Bristol, finishing there in 1918.⁠[1][2]

From 1918 to 1921 Dirac studied engineering at the University of BristolUniversity of BristolThe University of Bristol is a research university in Bristol, England, United Kingdom. It began as University College, Bristol, which opened in 1876, became a university under a royal charter in 1909 and is a member of the Russell Group.Open the full entry, graduating with a BSc in engineering in 1921.⁠[3][4]

In June 1921 Dirac sat the Cambridge scholarship examination and won an award from St John’s College, but it was not enough for him to go up. He instead studied mathematics at the University of Bristol for two further years, graduating with first-class honours in 1923.⁠[1][4]

While studying mathematics at Bristol, Dirac attended the physicist A. M. Tyndall’s lectures on the kinetic theory of gases and on quantum theory.⁠[5]

In 1923 Dirac went to St John’s College, Cambridge, as a research student in mathematical physics under Ralph Fowler. In May 1924 he completed his first paper on quantum theory, and four more papers by November 1925.⁠[6][3][1]

In the summer of 1925 Dirac read the proofs of a paper by Werner Heisenberg. In 1925–26 he gave the first complete formulation of quantum mechanics, building on Heisenberg’s matrix mechanics.⁠[3][1]

In 1926 Dirac and Enrico Fermi independently developed what became known as Fermi–Dirac statistics. In the same year Dirac received his PhD for a thesis entitled Quantum mechanics.⁠[3][1][6]

After working with Niels Bohr in Copenhagen, Dirac went to Göttingen in February 1927. That year he was elected a Fellow of St John’s College, holding a research fellowship there from 1927 to 1932.⁠[1][6]

In 1927 Dirac applied quantum mechanics to electromagnetic radiation, founding quantum field theory.⁠[3]

In 1928 Dirac developed a relativistic quantum theory of the electron, now known as the Dirac equation; the wave equation introduced special relativity into Schrödinger’s equation. The work appeared that year as Quantum Theory of the Electron.⁠[7][2]

In the same year Dirac made the first of many visits to the Soviet Union.⁠[1]

In 1929 Dirac made his first visit to the United States and travelled around the world, visiting Japan with Heisenberg.⁠[1][2]

He studied or worked as a visitor at universities in Copenhagen, Göttingen and Leiden, and at the universities of Wisconsin and Michigan and at PrincetonPrinceton UniversityPrinceton University is a private university and Ivy League member in Princeton, New Jersey. Chartered on October 22, 1746 as the College of New Jersey, it moved to Princeton in 1756 and adopted its present name in 1896. Undergraduate education leads to A.B. and B.S.E. degrees and emphasizes small-group discussion, independent research and residential college life. Graduate education spans the humanities, social sciences, natural sciences and engineering. As of October 2026, Christopher L. Eisgruber was president. Its 2026–27 operating budget was $3.407 billion, including $342 million for undergraduate aid.Open the full entry.⁠[2]

In 1930 Dirac published The Principles of Quantum Mechanics, which reached its third edition in 1947. In the same year he put forward his theory of holes and was elected a Fellow of the Royal Society (FRS).⁠[3][2][6]

In 1931 Dirac predicted the positron and, more generally, antiparticles, and made the first study of magnetic monopoles, returning to them in a second paper in 1948. The positron was discovered experimentally in 1932.⁠[3][2]

In 1932 Dirac became Lucasian Professor of Mathematics at the University of CambridgeUniversity of CambridgeThe University of Cambridge is a university in Cambridge, England, United Kingdom. It gives 1209 as its founding date, is made up of Schools, Faculties, Departments and autonomous Colleges, and is a member of the Russell Group.Open the full entry, a chair he held for 37 years until 1969; during this period he was a Professorial Fellow of St John’s College.⁠[1][6]

Dirac shared the 1933 Nobel Prize in Physics equally with Erwin Schrödinger “for the discovery of new productive forms of atomic theory.” At the time of the award he was affiliated with the University of Cambridge.⁠[8][9]

On December 12, 1933, Dirac delivered his Nobel Lecture, “Theory of Electrons and Positrons.”⁠[10]

In the same year he published early work on the Lagrangian in quantum mechanics, which later led to Richard FeynmanRichard FeynmanRichard Feynman (Richard Phillips Feynman, 1918–1988) was an American theoretical physicist who rebuilt quantum electrodynamics with the path-integral formulation and Feynman diagrams, for which he shared the 1965 Nobel Prize in Physics with Julian Schwinger and Sin-Itiro Tomonaga. He took part in the Manhattan Project during World War II and then taught for decades at the California Institute of Technology, where his introductory physics course became The Feynman Lectures on Physics; in 1986, as a member of the presidential commission investigating the space shuttle Challenger accident, he used ice water to demonstrate that the O-ring lost its resilience at low temperature.Open the full entry’s path integral formulation.⁠[3]

In 1934–35 Dirac visited Princeton, working at the Institute for Advanced Study; in 1934 he was a Visiting Professor there.⁠[1][2]

In January 1937 Dirac married Margit Wigner of Budapest in London; they had two daughters.⁠[1][2][11]

In 1937 Dirac published early work on large numbers in cosmology, and in 1938 he studied mass renormalization and radiation reaction in the theory of the electron.⁠[3]

Dirac received the Royal Society’s Royal Medal in 1939, gave its Bakerian Lecture in 1941 and was awarded the Copley Medal in 1952.⁠[6][7]

From 1958 to 1961 Dirac worked on constrained Hamiltonian dynamics, and in 1962 he put forward a theory of relativistic membranes.⁠[3]

In 1961 Dirac was elected to the Pontifical Academy of Sciences.⁠[2]

Dirac retired from the Lucasian chair in 1969 and moved to Florida, United States; from 1971 to 1984 he was Professor of Physics at Florida State University.⁠[1][6]

In 1973 Dirac was appointed to the Order of Merit (OM), an honour limited to 24 living holders at any one time.⁠[6][1]

Dirac lectured in Leningrad in 1973 and 1975, and in 1973–75 he proposed that constants of nature, such as Newton’s gravitational constant, may vary with time.⁠[1][3]

Dirac died in Tallahassee, Florida, United States, on October 20, 1984, and is buried there.⁠[9][11]

A memorial meeting for Dirac was held in Cambridge on April 19, 1985.⁠[1]

In the same year the Abdus Salam International Centre for Theoretical Physics (ICTP) first awarded the Dirac Medal, named after him. Proposed by Abdus Salam, the medal is awarded each year on Dirac’s birthday, August 8, to scientists who have made significant contributions to theoretical physics.⁠[12]

On November 13, 1995, a memorial stone to Dirac was unveiled in the nave of Westminster Abbey, near Isaac Newton’s monument. Carved by Lida Cardozo of the Kindersley workshop, it bears the words “1902 P.A.M. DIRAC O.M. PHYSICIST 1984” and the Dirac equation describing the behaviour of the electron.⁠[11][1]

Dirac is regarded as one of the founders of quantum mechanics and quantum electrodynamics; his research centred on the mathematical and theoretical foundations of quantum mechanics.⁠[7][6][2]

Fermi–Dirac statistics explain why particles with spin 1/2 cannot occupy the same quantum state.⁠[3]

The University of Bristol includes Dirac in its list of Nobel laureates, and its School of Physics names him among the renowned figures in its history.⁠[4][5]

Florida State University’s Paul A.M. Dirac Science Library is named after him, and the university’s Department of Physics and Department of Chemistry and Biochemistry each have a professorship named in his honour.⁠[13]