In 1921, with the assistance of the Danish government and the Carlsberg Foundation, he founded the Institute of Theoretical Physics in Copenhagen, where he served as director for the rest of his life. In 1920, he established the 'correspondence principle', the idea that classical physics and quantum physics will give the same answers when the systems become sufficiently large. During this time, he postulated that an atom would not emit radiation while it was in one of its stable states but rather only when it made a transition between states, and that the atom could neither absorb nor emit radiation continuously but only in finite steps or quantum jumps. In 1916, he became a full professor at the University of Copenhagen and continued his research. It was largely for this early work that Bohr was awarded the Nobel Prize in Physics in 1922, 'for his services in the investigation of the structure of atoms and of the radiation emanating from them'. In addition, he proposed that an electron could drop from a higher energy orbit to a lower one, emitting a photon of discrete energy in the process, which became part of the basis for quantum theory. He also introduced the idea that the electrons travel in discrete orbits around the atom's nucleus, the chemical properties of the particular element being largely determined by the number of electrons in the outer orbits. In 1913, on the basis of Rutherford's theories, Bohr developed and published his model of atomic structure, known as the Bohr model, which depicts the atom as a small, positively-charged nucleus surrounded by negatively-charged electrons that travel in circular orbits around the nucleus, similar in structure to the Solar System, but with electromagnetic forces providing attraction, rather than gravity.

The couple were to have six children: two died young, but the others went on to lead successful lives, with one, Aage Niels Bohr, also becoming a very successful physicist like his father, winning the Nobel Prize in Physics in 1975. On returning to Copenhagen from Manchester in 1912, Bohr took up a position as assistant professor at the University of Copenhagen, and also married Margrethe Nørlund. Thomson (the discoverer of the electron), and then at the University of Manchester under Ernest Rutherford (the discoverer of the nucleus and the structure of atoms). For his post-doctoral studies, Bohr moved to England, first conducting experiments at Trinity College, Cambridge under J. He completed his doctorate in 1911, under the physicist Christian Christiansen.

Niels’ younger brother, Harald, became a brilliant mathematician as well as an international footballer.īohr enrolled as an undergraduate at Copenhagen University in 1903, initially studying philosophy and mathematics, but switching to physics in 1905 after winning an essay competition with a report on the properties of surface tension. His father was a devout Lutheran and a respected professor of physiology at the University of Copenhagen his mother came from a prominent and wealthy Jewish family of bankers and parliamentarians. Niels Henrik David Bohr was born in Copenhagen, Denmark on 7 October 1885. He is recognized as one of the most influential physicists of the 20th Century, and received the Nobel Prize in Physics in 1922 “for his services in the investigation of the structure of atoms and of the radiation emanating from them”. He mentored and collaborated with many of the top physicists of the century at his institute in Copenhagen, where he and Werner Heisenberg developed the “Copenhagen interpretation” of quantum theory. In particular, he developed the Bohr model of the atom (and later the “liquid drop” model) and the principles of correspondence and complementarity. Niels Bohr was a Danish physicist who made fundamental contributions to understanding the structure of atoms and to the early development of quantum mechanics.

Niels bohr atomic model year