Evolution of the Quantum Theory

Abstract

The great new reformulation of quantum theory, which we know today as quantum mechanics, occurred mostly in 1925 and 1926. I shall not attempt to deal with the events of the past few years, on the ground that it is too soon to try to see them in historical perspective. But so great was the range of subject matter opened up for physics in the quantum-theoretical problems of the period 1925–40, that I shall have difficulty in even taking the barest notice of them in a short article.

Dr. Condon (Ph.D. California, 1926), who has been director of the National Bureau of Standards since 1945, has just been elected president of the Philosophical Society of Washington, the capital’s oldest scientific society. The University of Delhi and the New Mexico School of Mines have recently awarded him honorary of D. Sc. degrees, and the Royal Swedish Academy of Engineering Sciences has elected him a corresponding members in recognition of his contributions to science. His article is based on a paper presented in the Section B symposium on “Fifty Years of Quantum Theory” held during the December 1950 meetings of the AAAS in Cleveland, Ohio.