Michael Frayn - Copenhagen

Margrethe Niels, we agreed.

Bohr To talk about physics, yes.

Margrethe Not about politics.

Bohr I’m sorry.

Heisenberg No, no — I was simply going to say that I still have my old ski-hut at Bayrischzell. So if by any chance … at any time … for any reason …

Bohr Perhaps Margrethe would be kind enough to sew a yellow star on my ski-jacket.

Heisenberg Yes. Yes. Stupid of me.

Margrethe Silence again. Those first brief sparks have disappeared, and the ashes have become very cold indeed. So now of course I’m starting to feel almost sorry for him. Sitting here all on his own in the midst of people who hate him, all on his own against the two of us. He looks younger again, like the boy who first came here in 1924. Younger than Christian would have been now. Shy and arrogant and anxious to be loved. Homesick and pleased to be away from home at last. And, yes, it’s sad, because Niels loved him, he was a father to him.

Heisenberg So … what are you working on?

Margrethe And all he can do is press forward.

Bohr Fission, mostly.

Heisenberg I saw a couple of papers in the Physical Review . The velocity-range relations of fission fragments …?

Bohr And something about the interactions of nuclei with deuterons. And you?

Heisenberg Various things.

Margrethe Fission?

Heisenberg I sometimes feel very envious of your cyclotron.

Margrethe Why? Are you working on fission yourself?

Heisenberg There are over thirty in the United States. Whereas in the whole of Germany … Well.… You still get to your country place, at any rate?

Bohr We still go to Tisvilde, yes.

Margrethe In the whole of Germany, you were going to say …

Bohr… there is not one single cyclotron.

Heisenberg So beautiful at this time of year. Tisvilde.

Bohr You haven’t come to borrow the cyclotron, have you? That’s not why you’ve come to Copenhagen?

Heisenberg That’s not why I’ve come to Copenhagen.

Bohr I’m sorry. We mustn’t jump to conclusions.

Heisenberg No, we must none of us jump to conclusions of any sort.

Margrethe We must wait patiently to be told.

Heisenberg It’s not always easy to explain things to the world at large.

Bohr I realise that we must always be conscious of the wider audience our words may have. But the lack of cyclotrons in Germany is surely not a military secret.

Heisenberg I’ve no idea what’s a secret and what isn’t.

Bohr No secret, either, about why there aren’t any. You can’t say it but I can. It’s because the Nazis have systematically undermined theoretical physics. Why? Because so many people working in the field were Jews. And why were so many of them Jews? Because theoretical physics, the sort of physics done by Einstein, by Schrödinger and Pauli, by Born and Sommerfeld, by you and me, was always regarded in Germany as inferior to experimental physics, and the theoretical chairs and lectureships were the only ones that Jews could get.

Margrethe Physics, yes? Physics.

Bohr This is physics.

Margrethe It’s also politics.

Heisenberg The two are sometimes painfully difficult to keep apart.

Bohr So, you saw those two papers. I haven’t seen anything by you recently.

Heisenberg No.

Bohr Not like you. Too much teaching?

Heisenberg I’m not teaching. Not at the moment.

Bohr My dear Heisenberg — they haven’t pushed you out of your chair at Leipzig? That’s not what you’ve come to tell us?

Heisenberg No, I’m still at Leipzig. For part of each week.

Bohr And for the rest of the week?

Heisenberg Elsewhere. The problem is more work, not less.

Bohr I see. Do I?

Heisenberg Are you in touch with any of our friends in England? Born? Chadwick?

Bohr Hebenberg, we’re under German occupation. Germany’s at war with Britain.

Heisenberg I thought you might still have contacts of some sort. Or people in America? We’re not at war with America.

Margrethe Yet.

Heisenberg You’ve heard nothing from Pauli, in Princeton? Goudsmit? Fermi?

Bohr What do you want to know?

Heisenberg I was simply curious … I was thinking about Robert Oppenheimer the other day. I had a great set-to with him in Chicago in 1939.

Bohr About mesons.

Heisenberg Is he still working on mesons?

Bohr I’m quite out of touch.

Margrethe The only foreign visitor we’ve had was from Germany. Your friend Weizsäcker was here in March.

Heisenberg My friend? Your friend, too. I hope. You know he’s come back to Copenhagen with me? He’s very much hoping to see you again.

Margrethe When he came here in March he brought the head of the German Cultural Institute with him.

Heisenberg I’m sorry about that. He did it with the best of intentions. He may not have explained to you that the Institute is run by the Cultural Division of the Foreign Office. We have good friends in the foreign service. Particularly at the Embassy here.

Bohr Of course. I knew his father when he was Ambassador in Copenhagen in the twenties.

Heisenberg It hasn’t changed so much since then, you know, the German foreign service.

Bohr It’s a department of the Nazi government.

Heisenberg Germany is more complex than it may perhaps appear from the outside. The different organs of state have quite different traditions, in spite of all attempts at reform. Particularly the foreign service. Our people in the Embassy here are quite old-fashioned in the way they use their influence. They would certainly be trying to see that distinguished local citizens were able to work undisturbed.

Bohr Are you telling me that I’m being protected by your friends in the Embassy?

Heisenberg What I’m saying, in case Weizsäcker failed to make it clear, is that you would find congenial company there. I know people would be very honoured if you felt able to accept an occasional invitation.

Bohr To cocktail parties at the Germany Embassy? To coffee and cakes with the Nazi plenipotentiary?

Heisenberg To lectures, perhaps. To discussion groups. Social contacts of any sort could be helpful.

Bohr I’m sure they could.

Heisenberg Essential, perhaps, in certain circumstances.

Bohr In what circumstances?

Heisenberg I think we both know.

Bohr Because I’m half-Jewish?

Heisenberg We all at one time or another may need the help of our friends.

Bohr Is this why you’ve come to Copenhagen? To invite me to watch the deportation of my fellow-Danes from a grandstand seat in the windows of the German Embassy?