Copenhagen (2 page)

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.

Margrethe
  But if the Germans were trying to, Heisenberg would be involved.

Bohr
  There’s no shortage of good German physicists.

Margrethe
  There’s no shortage of good German physicists in America or Britain.

Bohr
  The Jews have gone, obviously.

Heisenberg
  Einstein, Wolfgang Pauli, Max Born … Otto Frisch, Lise Meitner .… We led the world in theoretical physics! Once.

Margrethe
  So who is there still working in Germany?

Bohr
  Sommerfeld, of course. Von Laue.

Margrethe
  Old men.

Bohr
  Wirtz. Harteck.

Margrethe
  Heisenberg is head and shoulders above all of them.

Bohr
  Otto Hahn—he’s still there. He discovered fission, after all.

Margrethe
  Hahn’s a chemist. I thought that what Hahn discovered …

Bohr
   … was that Enrico Fermi had discovered it in Rome four years earlier. Yes—he just didn’t realise it was fission. It didn’t occur to anyone that the uranium atom might have split, and turned into an atom of barium and an atom of krypton. Not until Hahn and Strassmann did the analysis, and detected the barium.

Margrethe
  Fermi’s in Chicago.

Bohr
  His wife’s Jewish.

Margrethe
  So Heisenberg would be in charge of the work?

Bohr
  Margrethe, there is no work! John Wheeler and I did it all in 1939. One of the implications of our paper is that there’s no way in the foreseeable future in which fission can be used to produce any kind of weapon.

Margrethe
  Then why is everyone still working on it?

Bohr
  Because there’s an element of magic in it. You fire a neutron at the nucleus of a uranium atom and it splits into two other elements. It’s what the alchemists were trying to do—to turn one element into another.

Margrethe
  So why is he coming?

Bohr
  Now your curiosity’s aroused.

Margrethe
  My forebodings.

Heisenberg
  I crunch over the familiar gravel to the Bohrs’ front door, and tug at the familiar bell-pull. Fear, yes. And another sensation, that’s become painfully familiar over the past year. A mixture of self-importance and sheer helpless absurdity—that of all the 2,000 million people in
this world, I’m the one who’s been charged with this impossible responsibility .… The heavy door swings open.

Bohr
  My dear Heisenberg!

Heisenberg
  My dear Bohr!

Bohr
  Come in, come in …

Margrethe
  And of course as soon as they catch sight of each other all their caution disappears. The old flames leap up from the ashes. If we can just negotiate all the treacherous little opening civilities …

Heisenberg
  I’m so touched you felt able to ask me.

Bohr
  We must try to go on behaving like human beings.

Heisenberg
  I realise how awkward it is.

Bohr
  We scarcely had a chance to do more than shake hands at lunch the other day.

Heisenberg
  And Margrethe I haven’t seen …

Bohr
  Since you were here four years ago.

Margrethe
  Niels is right. You look older.

Heisenberg
  I had been hoping to see you both in 1938, at the congress in Warsaw …

Bohr
  I believe you had some personal trouble.

Heisenberg
  A little business in Berlin.

Margrethe
  In the Prinz-Albrecht-Strasse?

Heisenberg
  A slight misunderstanding.

Bohr
  We heard, yes. I’m so sorry.

Heisenberg
  These things happen. The question is now resolved. Happily resolved. We should all have met in Zürich …

Bohr
  In September 1939.

Heisenberg
  And of course, sadly …

Bohr
  Sadly for us as well.

Margrethe
  A lot more sadly still for many people.

Heisenberg
  Yes. Indeed.

Bohr
  Well, there it is.

Heisenberg
  What can I say?

Margrethe
  What can any of us say, in the present circumstances?

Heisenberg
  No. And your sons?

Margrethe
  Are well, thank you. Elisabeth? The children?

Heisenberg
  Very well. They send their love, of course.

Margrethe
  They so much wanted to see each other, in spite of everything! But now the moment has come they’re so busy avoiding each other’s eye that they can scarcely see each other at all.

Heisenberg
  I wonder if you realise how much it means to me to be back here in Copenhagen. In this house. I have become rather isolated in these last few years.

Bohr
  I can imagine.

Margrethe
  Me he scarcely notices. I watch him discreetly from behind my expression of polite interest as he struggles on.

Heisenberg
  Have things here been difficult?

Bohr
  Difficult?

Margrethe
  Of course. He has to ask. He has to get it out of the way.

Bohr
  Difficult What can I say? We’ve not so far been treated to the gross abuses that have occurred elsewhere. The race laws have not been enforced.

Margrethe
  Yet.

Bohr
  A few months ago they started deporting
Communists and other anti-German elements.

Heisenberg
  But you personally …?

Bohr
  Have been left strictly alone.

Heisenberg
  I’ve been anxious about you.

Bohr
  Kind of you. No call for sleepless nights in Leipzig so far, though.

Margrethe
  Another silence. He’s done his duty. Now he can begin to steer the conversation round to pleasanter subjects.

Heisenberg
  Are you still sailing?

Bohr
  Sailing?

Margrethe
  Not a good start.

Bohr
  No, no sailing.

Heisenberg
  The Sound is …?

Bohr
  Mined.

Heisenberg
  Of course.

Margrethe
  I assume he won’t ask if Niels has been skiing.

Heisenberg
  You’ve managed to get some skiing?

Bohr
  Skiing? In Denmark?

Heisenberg
  In Norway. You used to go to Norway.

Bohr
  I did, yes.

Heisenberg
  But since Norway is also … well …

Bohr
  Also occupied? Yes, that might make it easier. In fact I suppose we could now holiday almost anywhere in Europe.

Heisenberg
  I’m sorry. I hadn’t thought of it quite in those terms.

Bohr
  Perhaps I’m being a little oversensitive.

Heisenberg
  Of course not. I should have thought.

Margrethe
  He must almost be starting to wish he was back in the Prinz-Albrecht-Strasse.

Heisenberg
  I don’t suppose you feel you could ever come to Germany …

Margrethe
  The boy’s an idiot.

Bohr
  My dear Heisenberg, it would be an easy mistake to make, to think that the citizens of a small nation, of a small nation overrun, wantonly and cruelly overrun, by its more powerful neighbour, don’t have exactly the same feelings of national pride as their conquerors, exactly the same love of their country.

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?