Person: Bohr, Niels
Niels Bohr is best known for the investigations of atomic structure and also for work on radiation, which won him the 1922 Nobel Prize for physics.
Mathematical Profile (Excerpt):
- Christian Bohr was awarded a doctorate in physiology from the University of Copenhagen in 1880 and in 1881 he became a Privatdozent at the university.
- In October 1891 Niels entered the Grammelholms school.
- During his last two years at school Niels specialised in mathematics and physics.
- There is certainly some evidence that he soon realised that the mathematics teacher did not have as good a grasp of the topic as he should have had, and that he became somewhat frightened of his exceptional pupil Bohr.
- In physics too Bohr studied texts ahead of the class finding errors in them.
- Bohr studied at the University of Copenhagen which he entered in 1903.
- Bohr was taught mathematics at university by Thorvald Thiele.
- At university Bohr could not carry out physics experiments since there was no physics laboratory.
- This paper is the only one that Bohr wrote describing experiments which he had carried out.
- By this time Bohr was engaged to Margrethe Norlund.
- Bohr applied to the Carlsberg Foundation for a travel grant in May 1911 and, after the award was made, went to England in September 1911 to study with Sir J J Thomson at Cambridge.
- He had intended to spend his entire study period in Cambridge but he did not get on well with Thomson so, after a meeting with Ernest Rutherford in Cambridge in December 1911, Bohr moved to the Victoria University, Manchester (now the University of Manchester) in March 1912.
- The timing was very fortuitous since shortly before Bohr and Rutherford met, Rutherford had published a major work showing that the bulk of the mass of an atom resided in the nucleus.
- In Manchester Bohr worked with Rutherford's group on the structure of the atom.
- Rutherford became Bohr's role model both for his personal and scientific qualities.
- Using quantum ideas due to Planck and Einstein, Bohr conjectured that an atom could exist only in a discrete set of stable energy states.
- Although Rutherford and Bohr had completely different personalities, they shared an enormous enthusiasm for physics and they also liked each other personally.
- However the relationship was never quite that of close friends since Bohr always saw Rutherford as his teacher.
- On 24 July 1912, with his paper still unfinished, Bohr left Rutherford's group in Manchester and returned to Copenhagen to continue to develop his new theory of the atom, completing the work in 1913.
- formed the foundation of Bohr's early reputation.
- The Bohr atom, although it has been superseded scientifically, persists even today in the minds of many people as a vivid image of what atoms look like and a symbol of physics.
- In July 1913 Bohr was appointed as a docent in Copenhagen.
- It was a bold move but Bohr's already high reputation meant that he would be taken seriously.
- Of course in 1914 times were uncertain and Bohr realised that no quick decision was likely.
- Bohr was in Manchester longer than he expected since his chair was not confirmed until April 1916.
- Four years earlier Bohr had left Manchester full of exciting but undigested ideas about the atom.
- In 1917 Bohr was elected to the Royal Danish Academy of Sciences and he began to plan for an Institute of Theoretical Physics in Copenhagen.
- Their social centre was the mansion "Gamle Carlsberg", given to the nation by the founder of the well-known brewery and placed at Niels Bohr's disposal in 1932.
- students and scholars of all nations gathered to eat and talk and listen to music, and often to sit quite literally at the feet of Bohr, trying to catch his challenging remarks, subtle comments and gentle jokes, spoken in his soft Danish voice.
- Bohr is best known for the investigations of atomic structure referred to above and also for work on radiation, which won him the 1922 Nobel Prize for physics.
- In a meeting at Como in north Italy in September 1927 Bohr put forward his principle of complementarity which gave a physical interpretation of Heisenberg's uncertainty relations.
- Bohr thought that his idea of complementarity could play an important role in fields other than quantum physics and he worked on these ideas throughout the rest of his life.
- It was Bohr's view of quantum theory which was eventually to become accepted.
- Einstein expressed grave doubts about Bohr's interpretation and Bohr, Einstein and Ehrenfest spent many hours in deep discussion, but Bohr's view prevailed.
- Bohr's other major contributions, in addition to quantum theory, include his theoretical description of the periodic table of elements around 1920, his theory of the atomic nucleus being a compound structure in 1936, and his understanding of uranium fission in terms of the isotope 235 in 1939.
- However Bohr was deeply concerned about the control of nuclear weapons and from 1944 he tried to persuade Churchill and Roosevelt for the need to have international cooperation.
Born 7 October 1885, Copenhagen, Denmark. Died 18 November 1962, Copenhagen, Denmark.
View full biography at MacTutor
Tags relevant for this person:
Astronomy, Origin Denmark, Prize Nobel, Physics
Adapted from other CC BY-SA 4.0 Sources:
- O’Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive