Bohr, Niels (1885–1962), along with Einstein, one of the two most influential physicists of the twentieth century.Bohr was born in Copenhagen, Denmark to affluent, well‐educated parents (his father was a professor of philosophy at the University of Copenhagen). Bohr became a professor at the University of Copenhagen in 1916 and in 1920 established the Institute for Theoretical Physics there, which quickly became a world‐recognized think tank frequented by the best scientific minds of the time. From this institute a new comprehension of the physical world emerged, which would have a profound impact on the remainder of the century and beyond: the observed and the observer were seen to interact; nature was both wave and particle; and philosophy and physics shared subject matter as issues of causality and interdeterminism were raised when Bohr and others deepened their understanding of nuclear fission.

In 1939, Bohr fled Denmark, accepting an invitation from the United States to participate in the Manhattan Project in Los Alamos, New Mexico. There he was instrumental in the development of the atomic bomb but ambivalent about its use as a weapon of mass destruction. Bohr spent the remainder of his life called for international control of nuclear weapons and the peaceful use of atomic energy.
[See also Arms Control and Disarmament: Nuclear; Atomic Scientists.]

Bibliography

Ruth Moore , Niels Bohr: The Man, His Science, and the World He Changed, 1966.
Abraham Pais , Niels Bohr's Times: In Physics, Philosophy, and Polity, 1991.

Peter J. McNelis