A rum lot, the English. Fine, civilised people, of course, liberal in politics, tolerant in social life, solicitous for the young and caring of the old. When it comes to the matter of what they consider funny, however, a strangeness enters, to the eyes of outsiders, at least. As one of the "characters" - what does one call the people invented by a hoaxer? - in Celia's Secret remarks, "The English sense of humour is something that I could write whole volumes about - but no one would laugh." Well, quite.
Here is the background. Michael Frayn's play Copenhagen began a highly successful, almost year-long run at the National Theatre in London in May 1998. The play has three characters, the physicists Werner Heisenberg and Niels Bohr, and Bohr's wife, Margrethe; the actors in that first production were Sara Kestelman, Matthew Marsh as Heisenberg, and David Burke as Bohr. The time is a timeless present, in which the three engage in a conversation beyond the grave. The subject they discuss, circling it like - the comparison is inevitable - electrons about the nucleus of an atom, is the mysterious visit which Heisenberg, Nazi Germany's leading scientist, paid to Bohr, his one-time friend and mentor, in 1941, at the Bohrs' house in Copenhagen, in occupied Denmark.
After initial, somewhat stilted pleasantries - Bohr was Jewish, and Heisenberg was working for the Nazis - the two men went out for a walk, during which they had a violent disagreement. When they returned to the house, Bohr as good as showed Heisenberg the door. Later, while the war was still on, Bohr escaped to America, where he worked on the Los Alamos atomic bomb project, that was to culminate in the destruction in 1945 of the Japanese cities of Hiroshima and Nagasaki. In 1947, Heisenberg, now a privileged detainee of the Allies, returned to Copenhagen, accompanied by a British Secret Service minder, and visited Bohr again, apparently to take up the subject that had divided them six years previously, but without success; Frayn quotes Heisenberg, from his somewhat self-serving memoir, Physics and Philosophy, to the effect that he and Bohr "both came to feel that is would be better to stop disturbing the spirits of the past".
So what did happen on that snowy walk, as Europe was plunging deeper and deeper into the abyss? Theories abound. It is highly probable that the point of contention between the two men was Germany's nuclear programme, in which Heisenberg was a leading figure. Did Heisenberg go to Copenhagen to pick Bohr's brain - Bohr, one of the greatest physicists of the century, was, with Heisenberg, one of the founders of Quantum Theory - or to warn him that Hitler's Bomb was a possibility, even if a remote one? We do not know, and probably never will know. In the play - which is well worth reading, if you have not seen a production of it, or, indeed, even if you have - Michael Frayn puts forward a compelling and highly dramatic answer. Frayn's drama is fascinating, subtle, at once passionate and cool, and highly skilled in its exposition of extremely complex scientific issues. It must have been hell to act in, night after night, with a matinee on Saturdays, through the long months of its run, and it is no wonder that under the strain at least one of the actors went . . . um, a little funny.
After the war, the team of scientists who had worked on the German nuclear programme, including Heisenberg, were brought to England and held under loose house arrest in the former Intelligence institution at Farm Hall, near Cambridge. They were treated well, and were left largely to their own devices. However, hidden microphones recorded all their conversations, for the Allies were anxious to find out just how close the Germans had come to building a bomb. The answer, it seems, is, not close at all. The team had built the rudiments of a nuclear reactor, but even if they had succeeded in making it work and had got it to "go critical", the absence of safeguards would have meant that the thing would have melted down, and melted its inventors along with it.
The main difficulty the Germans faced in their A-bomb project was producing Uranium-235 in sufficient quantities to construct an explosive device. One commentator, Thomas Powers, author of Heisenberg's War, believes that Heisenberg, unwilling to deliver atomic weapons into the hands of Hitler and his gang, deliberately refrained from working out a crucial diffusion equation that would have shown how to make a bomb from a few kilograms of U-235, rather than the tons the Germans believed it would require. Others, including Michael Frayn, are not convinced. All is uncertainty. And this is apt, since Heisenberg is the formulator of the celebrated Uncertainty Principle, which, as Frayn in a postscript to the text of his play tartly observes, "is one of those scientific notions that has become common coinage, and generalised to the point of losing much of its original meaning".
What the principle says, in essence, is that an observer of an event at the atomic level will not be able to measure simultaneously the position and the momentum of an atomic particle. Frayn: "The more precisely you measure one variable . . . the less precise your measurement of the related variable can be; and this ratio, the uncertainty relationship, is itself precisely formulable." We are all engaged, consciously or otherwise, in the quest for certainty. We want to know. Michael Frayn, for instance, desperately wanted to know the secrets that had died with Bohr and Heisenberg.
Imagine his excitement, then, when one morning in January 1999, as his play was preparing to transfer to a new London theatre, he received a letter signed "Celia Rhys-Evans", saying she had been to see his play, and was interested to hear the characters speak of Farm Hall, where she and her husband had lived for a time in the 1960s, and where she had found under the floorboards some papers written in German, a sheet of which she enclosed. Frayn, who knew some German, set about the task of translation, which was not easy, for much of the writing was gibberish, and seemed to consist of instructions for building a ping-pong table. Nevertheless, he persevered, meanwhile telling anyone who would listen, including the cast of the play, of the wonderful find he had made. Perhaps at last he would discover the explanations that had not been disclosed in the hours and hours of tape transcripts from those six months of monitored conversations at Farm Hall.
Celia's Secret is written in alternating chapters by Frayn and the actor who played Niels Bohr in the play, David Burke. In fact, as the reader soon discovers, Burke, an inveterate practical joker, was the real "Celia Rhys-Evans", and the page in German and the subsequent tantalising tidbits he had sent to Michael Frayn were fakes that he had got up. Why? Why did he do it, and, more interestingly, why did Frayn fall for it?
As to the latter, Frayn offers a rueful defence; the stuff Burke had written was so ridiculous that "No hoaxer could possibly have been idiot enough to try persuading anyone of such nonsense! It could only have been genuine!" < xo In the end, Frayn was tipped off that he was being hoaxed. And what did he do? He set out immediately to hoax the hoaxer, sending fake threatening letters to Burke, supposedly from the Ministry of Defence, demanding the return of confidential papers the Ministry had reason to believe were in his possession. Burke, however, was too old a hand to have his wrist burned in this way. There followed an elaborate cat-and-mouse game between the two principals, which ended with surrender on both sides, a laugh, a slap on the back, a clinking of glasses . . . Rum; distinctly.
The hero of the book, for this reader, is Matthew Marsh, who, knowing what Burke was up to, and feeling distinctly uncomfortable before the spectacle of a man as decent and gullible as Frayn being made a public fool of, told the playwright what was going on. How ironic, though, that it was Marsh who at the time was playing the part of Werner Heisenberg, that master of secrecy and close-mouthedness, and discoverer of the profound uses of uncertainty.
John Banville is Associate Literary Editor and Chief Literary Critic of The Irish Times