NIELS HENRIK BOHR

    Niels Henrik David Bohr was born in 1885 in Copenhagen. In 1908 he finished his studies. He left for Great Britain, where he worked for a few years with J.J.Thomson and E. Rutheford. In 1916 he became the head of the physics faculty at the Copenhagen University. He founded the Copenhagen Institute of Theoretical Physics and became its director. This Institute became one of the major centres for the development of the physics of atom in Europe.
    The most important achievement of Bohr was the development in 1913 of the theory of hydrogen atomic structure, which explained many observed phenomena. He helped develop the quantum theory. In 1928 he published the complementary principle which insisted on dual nature of matter - in some phenomena it takes on the character of a wave and in some - of a molecule. He worked on the theory of the atomic nucleus, which he described as a drop of heavy and incompressible liquid. Such a drop could undergo deformations similar to deformations of a drop of an actual liquid, for example mercury. That model, further developed by K. Ford, became one of the major models of the atomic nucleus. In 1939 he published - together with John Wheeler - the theory of atomic nucleus disintegration. In 1943 he escaped from occupied Denmark. He started working at Los Alamos on the construction of an atomic bomb.
    In 1922 Bohr received a Nobel prize.
    The scientist was admitted to many scientific societies world-wide. He also received numerous honoris causa doctor tittles (including one at the Warsaw University in Poland).
    One of the greatest scientists of the 20th century, he died in 1962.