Starting in August 2020, Boyle, PLLC
will feature a scientist or event notable in the history of the
development of quantum mechanics every month. For its inaugural post,
Boyle PLLC is pleased to highlight the life of Paul Adrien Maurice Dirac.
Subsequent features can be found here .
Paul Dirac was born August 8, 1902 in Bristol, England to a middle class family. Showing a talent for mathematics while in school, Dirac studied electrical engineering from 1918 to 1921 at Bristol University, but was unable to find a job in postwar England. As a consequence, he accepted an offer to study for a Bachelor of Arts degree in mathematics at Bristol University free of charge.
Graduating with honors from Bristol University in two years, Dirac then entered Cambridge University in 1923, where his supervisor, Ralph Fowler, was a specialist in statistical physics and atomic theory. By the time that Dirac completed his Ph.D. thesis at Cambridge University in 1926, he was an expert in the emerging field of quantum theory.
At that time, among quantum theorists, there was a drive to develop a wave equation for the electron that would be consistent with Einstein's theory of relativity (i.e., that would be relativistically invariant)—but that would not be a second-order equation. Dirac solved the problem in 1928. In, easily, one of the most elegant, and important works in physics, Dirac used linear algebra to define the square root of a second-order relativistically invariant equation. In this way, Dirac established a relativistically invariant linear equation that, today, bears his name.
The Dirac equation solved at least two puzzles at the time: explained electron "spin" and correctly predicted "fine structure" splitting in the spectrum of the hydrogen atom. Remarkably, and by examining the mathematical properties of his new equation, Dirac then predicted the existence of an anti-particle to the electron: today known as the positron.
From 1932 to 1969, Dirac held the Lucasian Chair of Mathematics at Cambridge University—a chair previously held by Isaac Newton. During this time, he continued to publish papers on quantum theory, gravitation, and cosmology. In 1933 Dirac shared the Nobel Prize in Physics with Erwin Schrödinger "for the discovery of new productive forms of atomic theory."
Upon retirement in 1969, Dirac became, first, a Visiting Professor, and then a full Professor at Florida State University in Tallahassee Florida. In 1984, Dirac died in Tallahassee, Florida.
Farmelo, G. The Strangest Man: The Hidden Life of Paul Dirac, Mystic of the Atom (Basic Books, New York, 2009).
Gamow, G. Thirty Years That Shook Physics: The Story of Quantum Theory (Doubleday & Co., New York, 1966).
Kragh, H. "Dirac, Paul Adrien Maurice," MacmIllan Encyclopedia of Physics, Vol. 1 (Macmillan Reference USA, New York, 1996).