Michael Frayn - Copenhagen

Bohr We obviously can’t go to the lecture.

Margrethe Not if he’s giving it at the German Cultural Institute — it’s a Nazi propaganda organisation.

Bohr He must know what we feel about that.

Heisenberg Weizsäcker has been my John the Baptist, and written to warn Bohr of my arrival.

Margrethe He wants to see you?

Bohr I assume that’s why he’s come.

Heisenberg But how can the actual meeting with Bohr be arranged?

Margrethe He must have something remarkably important to say.

Heisenberg It has to seem natural. It has to be private.

Margrethe You’re not really thinking of inviting him to the house?

Bohr That’s obviously what he’s hoping.

Margrethe Niels! They’ve occupied our country!

Bohr He is not they.

Margrethe He’s one of them.

Heisenberg First of all there’s an official visit to Bohr’s workplace, the Institute for Theoretical Physics, with an awkward lunch in the old familiar canteen. No chance to talk to Bohr, of course. Is he even present? There’s Rozental … Petersen, I think … Christian Moller, almost certainly.… It’s like being in a dream. You can never quite focus the precise details of the scene around you. At the head of the table — is that Bohr? I turn to look, and it’s Bohr, it’s Rozental, it’s Moller, it’s whoever I appoint to be there.… A difficult occasion, though — I remember that clearly enough.

Bohr It was a disaster. He made a very bad impression. Occupation of Denmark unfortunate. Occupation of Poland, however, perfectly acceptable. Germany now certain to win the war.

Heisenberg Our tanks are almost at Moscow. What can stop us? Well, one thing, perhaps. One thing.

Bohr He knows he’s being watched, of course. One must remember that. He has to be careful about what he says.

Margrethe Or he won’t be allowed to travel abroad again.

Bohr My love, the Gestapo planted microphones in his house. He told Goudsmit when he was in America. The SS brought him in for interrogation in the basement at the Prinz-Albrecht-Strasse.

Margrethe And then they let him go again.

Heisenberg I wonder if they suspect for one moment how painful it was to get permission for this trip. The humiliating appeals to the Party, the demeaning efforts to have strings pulled by our friends in the Foreign Office.

Margrethe How did he seem? Is he greatly changed?

Bohr A little older.

Margrethe I still think of him as a boy.

Bohr He’s nearly forty. A middle-aged professor, fast catching up with the rest of us.

Margrethe You still want to invite him here?

Bohr Let’s add up the arguments on either side in a reasonably scientific way. Firstly, Heisenberg is a friend.…

Margrethe Firstly, Heisenberg is a German.

Bohr A White Jew. That’s what the Nazis called him. He taught relativity, and they said it was Jewish physics. He couldn’t mention Einstein by name, but he stuck with relativity, in spite of the most terrible attacks.

Margrethe All the real Jews have lost their jobs. He’s still teaching.

Bohr He’s still teaching relativity.

Margrethe Still a professor at Leipzig.

Bohr At Leipzig, yes. Not at Munich. They kept him out of the chair at Munich.

Margrethe He could have been at Columbia.

Bohr Or Chicago. He had offers from both.

Margrethe He wouldn’t leave Germany.

Bohr He wants to be there to rebuild German science when Hitler goes. He told Goucdsmit.

Margrethe And if he’s being watched it will all be reported upon. Who he sees. What he says to them. What they say to him.

Heisenberg I carry my surveillance around like an infectious disease. But then I happen to know that Bohr is also under surveillance.

Margrethe And you know you’re being watched yourself.

Bohr By the Gestapo?

Heisenberg Does he realise?

Bohr I’ve nothing to hide.

Margrethe By our fellow-Danes. It would be a terrible betrayal of all their trust in you if they thought you were collaborating.

Bohr Inviting an old friend to dinner is hardly collaborating.

Margrethe It might appear to be collaborating.

Bohr Yes. He’s put us in a difficult position.

Margrethe I shall never forgive him.

Bohr He must have good reason. He must have very good reason.

Heisenberg This is going to be a deeply awkward occasion.

Margrethe You won’t talk about politics?

Bohr We’ll stick to physics. I assume it’s physics he wants to talk to me about.

Margrethe I think you must also assume that you and I aren’t the only people who hear what’s said in this house. If you want to speak privately you’d better go out in the open air.

Bohr I shan’t want to speak privately.

Margrethe You could go for another of your walks together.

Heisenberg Shall I be able to suggest a walk?

Bohr I don’t think we shall be going for any walks. Whatever he has to say he can say where everyone can hear it.

Margrethe Some new idea he wants to try out on you, perhaps.

Bohr What can it be, though? Where are we off to next?

Margrethe So now of course your curiosity’s aroused, in spite of everything.

Heisenberg So now here I am, walking out through the autumn twilight to the Bohrs’ house at Ny-Carlsberg. Followed, presumably, by my invisible shadow. What am I feeling? Fear, certainly — the touch of fear that one always feels for a teacher, for an employer, for a parent. Much worse fear about what I have to say. About how to express it. How to broach it in the first place. Worse fear still about what happens if I fail.

Margrethe It’s not something to do with the war?

Bohr Heisenberg is a theoretical physicist. I don’t think anyone has yet discovered a way you can use theoretical physics to kill people.

Margrethe It couldn’t be something about fission?

Bohr Fission? Why would he want to talk to me about fission?

Margrethe Because you’re working on it.

Bohr Heisenberg isn’t.

Margrethe Isn’t he? Everybody else in the world seems to be. And you’re the acknowledged authority.

Bohr He hasn’t published on fission.

Margrethe It was Heisenberg who did all the original work on the physics of the nucleus. And he consulted you then, he consulted you at every step.

Bohr That was back in 1932. Fission’s only been around for the last three years.

Margrethe But if the Germans were developing some kind of weapon based on nuclear fission …

Bohr My love, no one is going to develop a weapon based on nuclear fission.