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Niels Bohr

NIELS BOHR

1885 - 1962

Niels Henrik David Bohr is considered the father of the theory (the structure of the atom), and he was born in 1885 in Copenhagen, and in 1911 he obtained a doctorate in physics from the University of Copenhagen. Then he went to Cambridge, where he studied under the supervision of the English scientist Thompson, who had discovered the electron. Then Bohr moved to Manchester to study with Ernest Rutherford, who had discovered a few years before the atomic nucleus. Ruther Ford had suggested (contrary to previous opinions) that the atom It contains a heavy nucleus in the middle of which electrons are outside the nucleus. Bohr soon began discovering his new theory of the structure of the atom.

He said that the atom is like a miniature case of the solar system. The electrons revolve in their orbits around the heavy nucleus (which resembles the sun), but with a slight difference between the solar system and the atom, which is that while the planets revolve around the sun in orbits of different sizes, the electrons revolve around the nucleus with certain special sizes. Each orbit of these electrons has a certain energy associated with it. When the electron jumps from one orbit to another, it emits light with frequencies equal to the change in energy divided by Planck's constant.

Bohr's theory represents a breach of the ideas of classical physics. Many scientists, such as Einstein, welcomed Bohr's theory and considered it a scientific masterpiece. But many doubted the validity of that theory, and finally that theory was accepted, and in 1922 Bohr was presented with the Nobel Prize in Physics.

In 1920, the Institute of Theoretical Physics was opened in Copenhagen, and Bohr was appointed as its director. This institution has become under the management and supervision of Bohr. It attracted a large number of brilliant young scientists and soon became one of the leading centers of scientific research.

But difficulties returned to appear before Bohr's theory. Although the hydrogen atom has only one electron, this cannot be applied to other materials. Scientists were waiting for Bohr to amend his theory, but he could not.

As for the one who solved the problem, he was Werner Heisenberg. Heisenberg had studied in Copenhagen, where he benefited from Bohr. Bohr himself welcomed the new ideas presented by Heisenberg.

In 1930, Bohr directed his attention to the problem of the composition of the nucleus, and he developed the idea of ​​​​the complex nucleus in nuclear reactions, and he was the first to suggest that the radioactive uranium isotope is the isotope 235, which is responsible for atomic fission. This proposal was important in making the atomic bomb later.