But the first insight into the realm of antiparticles was gained at a desk, and not in the laboratory. Paul Dirac (1902 to 1984), the discoverer of the anti-world, was a gaunt, pale Englishman who was noticeable for his awkward behavior and his almost pathological reticence. Even in the community of quantum physics pioneers, which was not exactly short of eccentrics, Dirac was seen as exotic. The Danish physicist Niels Bohr described him as "the strangest man," while Albert Einstein was concerned about Dirac's balancing act between genius and madness.
Social settings made Dirac uncomfortable, and he even avoided working with others in his field, theoretical physics. In conversation, there were only three subjects which would prompt him to string together a few coherent sentences: Mickey Mouse, Chopin's waltzes and the singer Cher.
Dirac was happiest when he could be alone with his equations. His colleagues both admired and feared the brilliance of this eccentric Englishman.
According to a story related by the German physicist Werner Heisenberg, he and Dirac were once traveling on a ship to Japan together when Dirac asked him why he liked to dance. When Heisenberg explained that it was a pleasure to dance with nice girls, Dirac replied: "Heisenberg, how do you know beforehand that the girls are nice?"
Dirac was completely baffled by Robert Oppenheimer's interest in poetry. "In science," he is quoted as saying, "you want to say something that nobody knew before, in words which everyone can understand. In poetry you are bound to say ... something that everyone knows already in words that nobody can understand."
The Beauty of Equations
While Dirac seemed to lack the capacity for interpersonal relations, he was all the more obsessed with the elegance of formulas. Probably like no other physicist, he was guided by a desire for mathematical harmony. He was deeply convinced that the truth could be found in the beauty of equations.
It was no accident that Dirac, the magician of formulas, devised the equation that was named after him, an equation that his colleagues perceived as an "absolute miracle."
Dirac had long been searching for a new, improved theory of electrons when, at the end of 1927, he finally stumbled upon a formula of beguiling simplicity. Suddenly it seemed possible to explain the properties of the electron in a completely new way. Frank Wilczek, who, like Max Born, was later honored with the Nobel Prize, described Dirac's equation as "painfully beautiful." At only 25, Dirac had secured his place as a superstar in the relatively new field of quantum physics.
But there was a small problem. Dirac's theory described the electron precisely, but it also predicted the existence of a second, mysterious twin particle, albeit with opposite polarity. What were scientists to make of this strange quirk of mathematics?
At first, scientists tried in vain to make the troublesome ghost particle disappear with mathematical tricks. But it stubbornly resisted all of their efforts.
Messengers from the Universe