It has often been said that Dirac hated his father so much that he denied him an invitation to attend the Nobel ceremony.1 Plausible though the story sounds, it is probably untrue. The Nobel Foundation invited the laureates each to bring only one guest, but they could bring others if the prize-winner paid for their travel and accommodation.2 Heisenberg took his mother, and Schrödinger brought his wife, so it did not look at all odd that Dirac was accompanied only by his mother. She gave her husband a dose of his own medicine by not telling him about her trip until a few days before she set off, determined to make the most of her time away. She knew that, in only eleven days, she would back at the kitchen sink, the Cinderella of 6 Julius Road.3
Early on the Friday evening of 8 December 1933, Dirac and his mother were in the Swedish port of Malmö, waiting for the night train that would take them to Stockholm in time for breakfast. A few reporters spent several hours hunting for them all over Malmö and eventually tracked them down to a station café, which became the unlikely scene of a press conference. The journalists’ persistence was rewarded with a newsworthy interview with two prize eccentrics, ‘a very shy and timid boy’ and ‘a lively and talkative lady’.4
‘Did the Nobel Prize come as a surprise?’ asked one journalist. ‘Oh no, not particularly,’ Dirac’s mother butted in, adding, ‘I have been waiting for him to receive the Prize as hard as he has been working.’ She was so curious about Sweden that one reporter found himself answering her questions rather than asking his own – here was a woman who revelled in the attentions of the press. Dirac did not stay silent but was unusually forthcoming when the journalist from Svenska Dagbladet asked him how quantum mechanics applies to everyday life and was rewarded with a stream of insights into his unapologetic philistinism:
DIRAC: My work has no practical significance.
JOURNALIST: But might it have?
DIRAC: That I do not know. I don’t think so. In any case, I have been working on my theory for eight years and now I have started developing a theory that deals with the positive electrons. I am not interested in literature, I do not go to the theatre, and I do not listen to music. I am occupied only with atomic theories.
JOURNALIST: The scientific world that you have built during the past eight years, does it influence the way you look at everyday occurrences?
DIRAC: I am not that mad. Or rather, if it did [have such an influence] then I would go mad. When I rest – that is when I am at sleep of course also when I am taking a walk or when I am travelling – then I make a complete break with my work and my experiments. That is necessary so that there is no explosion here. (Dirac points to his head).
The story of the interview was on the news-stands in Stockholm station when the Diracs arrived shortly before eight o’clock in the morning. A quarter of an hour later, Heisenberg, Schrödinger and their guests stepped off the train and were met by a posse of dignitaries, all of them concerned that Dirac and his mother were nowhere to be seen. But when the photographers asked for the laureates and guests to pose, Dirac and his mother stepped forward into the flashes of the awaiting cameras. The welcoming committee was apparently too stunned to ask where they had been and only later heard what had happened: after Dirac’s absent-minded mother had failed to wake up when the train reached the station, she had been ejected by a guard, who had thrown her clothes, hairbrush and comb out of the carriage window.5 After the kerfuffle, the Diracs had made their way to the warm waiting room and had sat apart from the party of officials. When the group left the room, the Diracs followed them like a pair of ducks, without saying a word.
Heisenberg and Schrödinger obliged the press with interviews, but Dirac wanted to escape to the hotel as quickly as politeness allowed.6 He and his mother were accompanied on the short chauffeur-driven journey to their hotel by the Nobel Foundation’s attaché Count Tolstoy, a grandson of the novelist and a polished diplomat. His first challenge was to sort out the Diracs’ accommodation in the 500-room Grand Hotel, overlooking the harbour. The staff must have thought they had done Dirac a favour by putting him and his mother in the bridal suite, but Flo was having none of that and demanded a room of her own. After making plain his displeasure, Dirac – about to pocket his prize money, approximately £200,000 in today’s money – took the cost on the chin.
While Heisenberg and Schrödinger were relaxing in their baths, Dirac escaped the gaggle of journalists by leaving the hotel surreptitiously, taking his mother with him. They were then free to walk anonymously around the chilly city, in its best suit for the Nobel celebrations, a pre-Christmas festival unique to Stockholm. It looked like fairyland when darkness fell, the firs and Christmas trees lit up with coloured electric lights, the murmurings of the crowd accompanied by the tinkling of lounge pianists and the occasional cry of a seagull overhead.
Flo was not going to be deprived of press attention for much longer. While Dirac was resting, she held court with four journalists, inviting them separately to her suite to talk about her son and to show them the frocks, furs and jewellery he had bought her. The reporters already knew she was a colourful character, but they were not prepared for her torrent of maternal ardour, delivered in words that resembled ‘shattering beads of quicksilver’, as the Svenska Dagbladet put it. In the interviews, her eyes darted around as she delivered a disjointed, stream-of-consciousness lecture, as if she had been given two minutes to convince them that her son was Superman. One of her targets was the Nobel authorities, who had shamefully credited her son only as ‘Dr Dirac’ when he is ‘the top professor in the world!’
Asked about life at home, Mrs Dirac laid into his father, ‘the domestic tyrant’, a man who hated wasting time and whose motto was ‘work, work, work’. Not mentioning Felix, she described how Charles leant heavily, and unnecessarily, on the young Paul to study, not allowing him to play with other boys: ‘If the boy had shown any other tendencies they would have been stifled. But that stifling was not necessary. The boy was not interested in anything else.’
As a result, Dirac had never known what it was to be a child. None of the journalists appears to have asked her if she took any responsibility for this; it was all the fault of her husband, she thought. When a reporter enquired whether Dirac’s father was happy about his son’s success, Flo replied disingenuously: ‘I would not say so. The father has been surpassed and he doesn’t like it.’ What of her son’s interest in the opposite sex? ‘He is not interested in young women […] despite the fact that the most beautiful women of England are in Cambridge.’ The only women he cares for are his mother, his sister and ‘perhaps ladies with white hair’ (she may have been referring to Isabel Whitehead).7 Since Flo had vetoed the visit of Felix’s girlfriend a decade earlier, possibly before, Dirac had known that his mother feared that young women would be attracted to him, and her attitude had not changed.
On the following day, the Stockholm news-vendors sold newspapers with headlines that included ‘Thirty-One-Year-Old Professor Dirac Never Looks at Girls’.
Early on Sunday evening, hundreds of coiffed men and women packed the galleries at the Stockholm Concert Hall to witness the King’s presentation of the prizes. At 5 p.m. sharp, a blazing chorus of trumpets silenced the crowd before the opening of the two huge doors into the room where the prizes would be awarded. Each of the laureates, escorted by one of the Swedish hosts, marched to their separate armchairs by the platform, covered in red velvet and decorated with banks of pink cyclamen, maidenhair ferns and palms. The national flags of the new laureates hung overhead alongside Sweden’s. The prize-winners were in the customary starched white shirt and bow tie, and all of them wore dinner suits, except Dirac, who won the sartorial booby prize by wearing a pitifully old-fashioned dress suit. He bowed low to the King before accepting his medal and certificate and then bowed several times to the crowd amid tumultuous applause. Compared with Heisenberg, Dirac looked pallid and sickly: he looked ‘far too thin and stooping’, one reporter worried, adding that ‘All the motherly ladies warmly hoped
that he should feed up and get the time to exercise and enjoy himself a bit.’8
After the ceremony, the laureates were driven back to the Grand Hotel to attend the Nordic midwinter feast of the Nobel Banquet, in the winter garden of the Royal Salon. Even by the standards of Cambridge this was a spectacular setting for a dinner: the tables, lit with hundreds of bright-red candles in silver holders, were arranged in a horseshoe shape around the water fountain in the centre of the room. There were three hundred guests, every woman in her most scintillating gown, every man in a dinner jacket, except Dirac.9 At the top table, men were seated alternately with women.10 On a balcony above, liveried musicians played, in competition with canaries chirruping in their cages near the glass roof.
After the speeches, a silent toast to the memory of Alfred Nobel and the singing of the Swedish national anthem, a fleet of waiters began to deliver the first course from a menu that featured game consommé, sole fillets with clams and shrimps and fried chicken with vegetable-stuffed artichokes. The climax was the chef’s pièce de résistance dessert: ice-cream bombes that shone in the dark after they had been doused in alcohol and set alight.11 Afterwards, each laureate was expected to make a short speech, customarily a few pieties of gratitude and reflection, laced with self-deprecating wit. After the first speech – given by Ivan Bunin, winner of the prize for literature – Dirac rose from his seat and walked to the rostrum, where, as usual, he shed his shyness. After paying his compliments to the hosts, he declared that he was not going to speak about physics but, instead, wanted to outline how a theoretical physicist would approach the problems of modern economics. This was just the kind of applied thinking that Bernal and his colleagues had been urging Dirac to do, but they might have expected him to choose a different venue for his first public comment on social and economic affairs. Nervous glances were exchanged round the great hall as he leaned over the rostrum and presented an argument that all the economic troubles of the industrialised world stemmed from a fundamental error:
[W]e have an economic system which tries to maintain an equality of value between two things, which it would be better to recognise from the beginning as of unequal value. These two things are the receipt of a certain single payment (say 100 crowns) and the receipt of a regular income (say 3 crowns a year) through all eternity. The course of events is continually showing that the second of these is more highly valued than the first. The shortage of buyers, which the world is suffering from, is readily understood, not as due to people not wishing to obtain possession of goods, but as people being unwilling to part with something which might earn a regular income in exchange for those goods. May I ask you to trace out for yourselves how all the obscurities become clear, if one assumes from the beginning that a regular income is worth incomparably more, in fact infinitely more, in the mathematical sense, than any single payment?
Without bothering to suggest how his explanation could be tested, he concluded with a Rutherfordian swipe at science popularisers, informing the diners that once they had done their homework, they will have ‘a better insight into the way in which a physical theory is fitted in with the facts than you could get from studying popular books on physics’.12 After thanking the audience for its patience, he returned to his seat. A spatter of clapping gradually gathered into firm applause, many of the diners laughing nervously and apparently wondering what to make of Dirac’s speech. Heisenberg and Schrödinger did not follow suit by talking about economics and politics; speaking in German, they gave speeches that followed the convention of steering clear of anything that might be politically controversial.
Dirac’s reasoning puzzled Schrödinger and his wife, and Anny described it as a ‘tirade of communist propaganda’.13 But if the written record of Dirac’s speech is accurate, she was being unfair: Dirac was addressing a topic of theoretical economics that transcended politics. He was also wrong: his theory is approximately correct only when interest rates are always low, but he had not taken into account that it makes good sense to take the lump sum if interest rates are high and remain so.14 If Dirac had bothered to consult a professional economist, such as his Cambridge colleague John Maynard Keynes, he would have been spared posterity’s judgement that in his first foray outside his own field he had talked nonsense. And he had done so in the glare of the Nobel spotlight.
Dirac’s fallacy seems to have gone unnoticed or, at least, unremarked in the after-dinner levity. Flo watched Heisenberg and Schrödinger closely as they laughed and joked with the other guests, while Dirac strained to make conversation and occasionally disappeared from gatherings, as if vanishing into thin air. Flo kept a sharp eye on Schrödinger, not caring much for his braggadocio: by far the oldest of the trio of physics prize-winners, he kept trying to assert himself as their leader, though Heisenberg and Dirac declined to follow him. She also noticed that Schrödinger and his wife ‘terribly resent’ that he had to share his prize with her son. More to her liking was the genial Heisenberg and his mother, dressed like a Dresden shepherdess. Flo admired Heisenberg for having ‘no swank at all’, although she thought him a ‘terrible flirt’, like her son, and she complained that both of them cruised the circles of adoring ladies before they ran ‘back to [their] poor, tired mother [s] whenever they have had enough’.15 She had not previously seen Dirac in the company of admiring young women, and she did not like it: whether or not she noticed, he was drifting away from her.
The lavish hospitality continued for four days, unabated. Dirac’s only task was to give his Nobel lecture on the Tuesday afternoon, traditionally an opportunity for the laureates to present their work to other academics. Dirac spent most of his twenty-minute presentation on ‘The Theory of Electrons and Positrons’, describing how quantum mechanics and relativity made possible ‘the prediction of the positron’. This was the first time he had referred to his speculation about the positron as a prediction, and he went on to repeat another of his speculations, with more confidence than usual: ‘It is probable that negative protons can exist.’ Finally, after pointing out the apparent symmetry between positive and negative charge, he hinted that the universe might consist of equal amounts of matter and anti-matter:
[W]e must regard it as an accident that the Earth (and presumably the whole solar system), contains a preponderance of negative electrons and positive protons. It is quite possible that for some of the stars it is the other way about, these stars being built up mainly of positrons and negative protons. In fact, there may be half the stars of each kind.16
He had glimpsed a universe made from equal amounts of matter and anti-matter in which, for some unknown reason, human experience is confined almost entirely to matter. But was this a speculation or a prediction? The audience had good reason to be unsure.
Dirac appears to have been unaware that he was not the first to imagine a universe made of both matter and anti-matter. In the high summer of 1898, soon after J. J. Thomson had discovered the electron, the Manchester University physicist Arthur Schuster had hatched a similar idea. In a light-hearted article in a summer edition of Nature, he conceived a universe made of equal amounts of ‘matter and anti-matter’, based on the bizarre idea that atoms are sources of invisible fluid matter that flow into sinks of anti-atoms.17 But Schuster’s whimsy lacked substantial underpinnings from reason or observation and so remained a ‘holiday dream’, as he termed it. Within a decade, it was forgotten.
After the Nobel festivities, most of the prize-winners usually return home. But Dirac, Heisenberg and their mothers moved on to yet more celebrations, in Copenhagen. Bohr, probably wanting a piece of the action, threw a grand party in their honour on the Saturday evening at his mansion. Schrödinger, not a member of Bohr’s inner circle, declined his invitation and returned to Oxford, where he was living, having fled Germany a few months before. His colleagues in England looked askance at his personal life – he lived with his wife and his mistress – and he, in return, despised the colleges as ‘academies of homosexuality’.18
Dirac’s mot
her had heard many stories about the agreeable life at the court of Bohr, and she was not disappointed. Bohr’s was a ‘commanding’ presence, Flo observed, and she was charmed by his wife Margrethe, whose donnish air was lightened by her daring dress, a green morning frock trimmed with leopard skin and yellow beads.19 The Bohr residence was looking resplendent: the sprays of winter flowers and ferns, the statues, the cubist painting hanging above the grand piano, the huge windows overlooking acres of garden and woodland. For Flo, this opulence had done nothing to spoil the family, least of all the Bohrs’ five playful but well-behaved boys.
Bohr was out during the guests’ first evening at the house and returned to find that Dirac had been the first to retire to bed. Unwilling to lose precious time, Bohr bounded up to Dirac’s room and brought him downstairs for a discussion that lasted into the small hours. She could now see why Dirac held Bohr in such affection: here was an older man, authoritative but not authoritarian, forceful but not intimidating, able to bring out the best in everyone. It may well have crossed Flo’s mind that Bohr would have been the perfect father for her son.
The Bohrs’ party would not have disgraced one of the Nobel Foundation’s receptions. In the mansion’s main hall, three hundred guests sat at tables under the huge glass roof, drinking the endless supplies of champagne, beer and wine and eating the food from the generous buffet. When everyone had eaten, Bohr stood in the centre of the hall and gave a speech in English, subtly ensuring that no one overlooked his contribution to the achievements of his ‘young pupils’. Heisenberg replied, in German, but Dirac said nothing; throughout the speeches, he stood behind a pillar. After the toasts, Bohr steered the party into the drawing room for a cabaret from a pink-frocked American singer accompanied by the Danish virtuoso Gertrude Stockman and, inevitably, by Heisenberg at the piano.
The Strangest Man Page 35