Neils Bohr was born on this day in 1885

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BOHR (bohr)

Danish physicist

Common clues: Einstein contemporary; Los Alamos scientist; Quantum physics pioneer; Danish physicist; Nobelist Niels ____; Atomic physicist Niels

Crossword puzzle frequency: 2 times a year

Frequency in English language: 39594 / 86800

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Video: Quantum Physics – Einstein and Neils Bohr

Anyone who is not shocked by quantum theory has not understood a single word ~ Niels Bohr

Niels Henrik David Bohr (October 7, 1885 – November 18, 1962) was a Danish physicist who made essential contributions to understanding atomic structure and quantum mechanics.

In 1941, during the German occupation of Denmark in World War II, Bohr was visited by Heisenberg in Copenhagen (see next section). In 1943, shortly before he was to be arrested by the German police, Bohr escaped to Sweden, and then travelled to London.

He worked at the secret Los Alamos laboratory in New Mexico, USA, on the Manhattan Project, where, according to Richard Feynman, he was known by the assumed name of Nicholas Baker for security reasons. However his role in the project was minor. He is quoted as saying "That is why I went to America. They didn't need my help in making the atom bomb." He was seen as a knowledgeable consultant or "father confessor" on the project. After the war he returned to Copenhagen, advocating for a peaceful use of nuclear energy. He died in Copenhagen in 1962.

The element bohrium is named in his honor.

Werner Heisenberg claimed in an interview after the war, when the author Robert Jungk was working on the book Brighter Than a Thousand Suns, that he had tried to establish a pact with Bohr such that scientists on neither side should help develop the atomic bomb. He also said that the German attempts were entirely focused on energy production, and that his circle of colleagues tried to keep it that way. Heisenberg nuanced his claims, though, and avoided implication that he and his colleagues had purposely sabotaged the bomb effort. However, this nuance was lost in Jungk's original publication of the book, which strongly implied that the German atomic bomb project was rendered purposely stillborn by Heisenberg.

When Bohr saw this depiction in the Danish translation of Jungk's book, he disagreed wholeheartedly. He said that Heisenberg had indeed let him know in Copenhagen that he was working on an atomic bomb project, and that he thought that Germany would win the war. He dismissed the idea of any pact as an after-the-fact construction. He drafted several letters to inform Heisenberg about this but never sent any of them. Michael Frayn's play Copenhagen, which ran on Broadway for a time, explores what might have happened at the 1941 meeting between Heisenberg and Bohr. The truth of the historical event is still a matter of scholarly debate.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Niels Bohr".