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Niels Bohr's atom model turns 100

In his model, electrons orbitted the nucleus like planets around the sun. This year is the centennial of Niels Bohr’s paper

“Prediction is very difficult, especially about the future”.

The words are by Niels Bohr, the father of the atom as we know it.

And he was right. Take for example the three scientific papers on the atomic model he published in 1913: No-one could have foreseen the ubiquitous effect these discoveries have on our lives, one century later. It is thanks to quantum mechanics, based on Bohr’s theory, that we can charge our laptops, and google search for whatever we like.

Niels Bohr, ironically known as ‘the Pope’ among his colleagues, was born in 1885, in Copenhagen, where he lived for most of his life. He created the Institute for Theoretical Physics, now known as the Niels Bohr Institute, where he mentored and collaborated with the best scientists of his time.

A ground breaking trilogy

“The three papers by Bohr, also known as ‘The Trilogy’, were ground breaking because for the first time they described how atoms work” says Troels Petersen, associate professor of experimental particle physics at the Niels Bohr Institute, to the University Post.

“In this way, the structure of the matter could be explained from basic principles. Combining previous works Bohr produced a new model, governed by new quantum laws, where electrons orbit around the nucleus like planets around the sun,” he adds.

“This gave answers to many unsolved questions, not the least why atoms do not collapse! Bohr also realized that electrons can change orbit only by emitting or absorbing a photon of discrete energy. All this is the basis of the so-called original quantum theory, for which Bohr received the physics Nobel prize in 1922.”

The short film below explains the context of his model and follows Finn Aaserud, director of the Niels Bohr Archive, through the archives where Niels Bohr’s papers are kept (refresh page if this does not load).

(Film by Experimentarium, Niels Bohr Archive, and the Lundbeck Foundation)

Man of many interests

Bohr’s interests ranged from philosophy to soccer. He was influenced by the work of Søren Kierkegaard and usually played as a goalkeeper. But the family’s football star was his younger brother Harald, who played in the Danish national team and won the silver medal at the 1908 Summer Olympics.

Niels Bohr had six children. One of them, Aage, was awarded the physics Nobel Prize in 1975.

Bohr believed in the importance of sharing knowledge about nuclear research. In 1950 the United Nations, following his suggestions, created the International Atomic Energy Agency (IAEA).

Book, conferences and more

The Niels Bohr Institute and other institutions are planning various events to celebrate the 100th anniversary of Niels Bohr’s atomic model. A complete list can be found here.

Oxford University Press will publish a book on the Trilogy in the light of the extensive correspondence between Niels Bohr and his wife, Margrethe Nørlund. A History of Science Conference is organized in June and a meeting on the “Quantum Century” will follow in October.

In July, the world most talented high school students will compete for the 2013 International Physics Olympiads, which will be in Copenhagen.

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