Copenhagen (play)

Copenhagen is a play by Michael Frayn, based around an event that occurred in Copenhagen in 1941, a meeting between the physicists Niels Bohr and Werner Heisenberg. It debuted in London in 1998 and in 2000 won the Tony Award for Best Play.

Contents

The play

The play contains three characters: Heisenberg, Bohr, and Bohr's wife Margrethe. Its temporal and spatial location was purposely vague, suggesting that the three were spirits in some sort of timeless, ethereal realm of some sort, reflecting on past events and interpretations.

Bohr and Heisenberg were friends and had collaborated together and were influential in developing quantum theory before World War II. Heisenberg in 1941 was in charge of the German effort to develop atomic energy for practical purposes (possibly including an atomic bomb). Bohr's native Denmark was occupied by Germany, and he was under severe restrictions on what he could work on, and was in a position of potential danger because he was considered half-Jewish.

At one point in Heisenberg's visit with Bohr, they went outside for a walk so that they could speak without fear of being monitored by the Gestapo. The walk was however brief: Bohr came back, furious. The two formerly close companions were never again good friends.

There is considerable speculation on what occurred at the real-life meeting, and the actual accounts of it from the parties involved differ. The pro-Bohr version of the story asserts that Heisenberg was seeking to recruit Bohr to the Nazi nuclear effort, and offering him academic advancement in return. The pro-Heisenberg version asserts that Heisenberg was attempting to give Bohr information about the state of the German atomic programme, in the hope that he might pass it to the Allies through clandestine contacts. At that point the German atomic programme was not progressing well (the Nazi government had decided not to undertake the investment required to develop a weapon during the war); Heisenberg may have suspected that the Allies had a viable atomic programme, and hoped that by disabusing them of the idea that the German programme was also successful he could dissaude the Allies from using an atom bomb on Germany.

These and other possibilities are considered in the play, and it is the uncertainty that makes it interesting. Two concepts which Frayn uses as overarching metaphors in the play are the most famous scientific theories associated with Bohr and Heisenberg: Bohr's idea of complementarity (by which a photon can be regarded as both a wave and a particle, depending on how one looks at it) and Heisenberg's idea of the uncertainty principle (by which it is impossible to know the exact momentum and location of a particle at the same time, because the measurement of one property affects the other). Frayn stresses the complementarity of language (by which an ambigious statement can be seen in a number of ways) and the uncertainty of history (by which looking backwards at the past clouds our ability to fully understand it).

Bohr was later smuggled out of Denmark (it is insinuated in the play that Heisenberg may have had a role in this, likely saving his life), and went to work on the Allied effort to produce nuclear weapons at Los Alamos. By the time Germany lost the war in 1945, Heisenberg had only to almost construct the first self-sustaining chain reaction in a primitive nuclear reactor in a cave, without proper safety equipment. He made it into a zone of Allied occupation and was later moved to Farm Hall, Great Britain, where he and other German scientists were kept under observation as part of an Allied attempt to discover the full extent of the German bomb program.

The play was adapted as a television movie in 2002, with Daniel Craig as Heisenberg, Stephen Rea as Niels Bohr, and Francesca Annis as Margrethe Bohr. The movie substantially cuts down the script of the play, eliminating several recurring themes, and most of the material that established the community of scientists in Copenhagen. It also abandons the abstract staging of the theatrical version in favor of being set in the city of Copenhagen, in Bohr's old house.

Historical debate

Heisenberg historians remain divided over their own interpretations of the event, and the 1998 play put more attention on what had been a previously primarily scholarly discussion.

Much of the initial "controversy" resulted from a 1956 letter Heisenberg sent to the journalist Robert Jungk after reading the German edition of Jungk's book Brighter than a Thousand Suns (1956). In the letter, Heisenberg described his role in the German bomb project. Jungk published an extract from the letter in the Danish edition of the book in 1956 which, out of context, made it look as if Heisenberg was claiming to have purposely derailed the German bomb project on moral grounds. (The letter's whole text shows Heisenberg was careful not to claim this.) Bohr was outraged after reading this extract in his copy of the book, feeling that this was false and that the 1941 meeting had proven to him that Heisenberg was quite happy with producing nuclear weapons for Germany.

After the play inspired numerous scholarly and media debates over the 1941 meeting, the Niels Bohr Archive in Copenhagen released to the public all heretofore sealed documents related to the meeting, a move intended mostly to settle historical arguments over what they contained. Among the documents were the original drafts of letters Bohr wrote to Heisenberg in 1957 about Jungk's book and other topics. The documents added little to the historical record but were interpreted by the media as supporting the "Bohr" version of the events.

Frayn has said the play was inspired by Thomas Powers' book Heisenberg's War: The Secret History of the German Bomb (Knopf, 1993).

See also

External links

See also: Copenhagen (play), 1941, 1945, 1956, 1998, 2000, 2002, ALSOS, Atomic bomb, Complementarity