Niels Bohr

Who is Niels Bohr?

Niels Bohr was a Danish physicist born in Copenhagen in 1885 who made foundational contributions to understanding atomic structure and quantum theory. In 1913 he proposed the Bohr model of the atom, in which electrons occupy discrete energy levels and emit or absorb radiation when they jump between them, reconciling classical physics with early quantum ideas. For this work he received the Nobel Prize in Physics in 1922. He developed the principle of complementarity and, with Werner Heisenberg, shaped the Copenhagen interpretation of quantum mechanics. In 1921 he founded the Institute for Theoretical Physics in Copenhagen (now the Niels Bohr Institute), which became a leading centre attracting physicists from around the world. During the Second World War he fled Nazi-occupied Denmark and briefly contributed to Allied atomic research, afterwards becoming a prominent advocate for the peaceful use of atomic energy and open scientific cooperation. He died in Copenhagen in 1962; the element bohrium is named in his honour.

Sources: Niels Bohr, 'On the Constitution of Atoms and Molecules' (Philosophical Magazine, 1913) · Nobel Prize in Physics 1922 (nobelprize.org) · Abraham Pais, 'Niels Bohr's Times' (1991)