Page 2 of 2
Seed: The book includes several revelatory passages documenting Dirac’s personal life. How did you research and verify that material?
GF: I devoted a lot of time tracking down Dirac’s surviving friends, people who knew him very well. The most important one I found was his last great friend, Leopold Halpern, an expert on relativity who slept in the open air, refused to wash with soap, and liked to slice open baked potatoes with a karate chop. A few years ago, when Halpern was at death’s door with prostate cancer, he flew across the country to Florida, where Dirac spent the latter part of his life, just so he could row me up Wakulla Springs. He and Dirac used to go rowing every weekend. That was a special trip for me: Even now I’m looking at my arm and there are goose bumps. He showed me places where they talked, even where they went skinny dipping. Two and a half months later, Halpern died.
I spent several months consulting the Dirac archive at Florida State University in Tallahassee, which was virtually untouched. Dirac was an FSU professor for the last 14 years of his life. I found amazing things, not just letters from great physicists like Heisenberg and Schrödinger but also an amazing cache of weekly letters from Dirac’s mother, spanning almost 20 years. Many historians would’ve probably turned their noses up at these, but I found in them a dramatic story that illuminates Dirac’s home life and upbringing. I was also blessed with beginner’s luck when I happened to meet Dirac’s younger daughter at a centenary celebration of his birth. We hit it off well, and one day in her kitchen while I was visiting her, she showed me something like 120 private letters between Dirac and his first serious girlfriend, later his wife. Keep in mind, this man hardly spoke a word, and here he was opening up, writing whole pages—epics for him. I couldn’t believe my luck. Here was Dirac talking about his father with whom he didn’t get along at all, and about what it felt like to be someone conscious, that he was unlike most other people, unable to empathize with them. This is just my opinion here, but I believe he demonstrated many symptoms of what we now call autism, though that condition had not been identified at the time.
Seed: You think Dirac had undiagnosed autism?
GF: I did not go into this book project thinking Dirac was autistic in any way. When I started researching him all those years ago, I barely even knew what the term “autism” meant, and certainly didn’t apply it to Dirac. But as I researched, I encountered rumors about Dirac being autistic, about Einstein being autistic, and speculations that autism was more prevalent in scientists and mathematicians. So during one of my stays at Cambridge, I went to see Simon Baron-Cohen, who is arguably Britain’s leading expert on autism. He knew nothing about Dirac, but, to my amazement, he began describing patterns of behavior that exactly correspond to Dirac’s. Let me stress that this is just a hypothesis, and that I’m personally very skeptical of attempts to psychoanalyze people who are dead. This isn’t theoretical physics; I can’t do a slam-dunk experiment to prove it.
Seed: What were some of the behavioral indicators?
GF: There are many of them: inability to empathize, extreme taciturnity and literal-mindedness, a passion for a routine, narrow interests, a lack of physical coordination, dislike of sudden loud noises, and so on. Many of the “Dirac stories” told by physicists are, in my opinion, actually autism stories. When people are laughing at these things, they forget what they’re actually doing is mocking.
Seed: Do you think those traits might have helped him in his work or given him a unique perspective?
GF: Well, he was certainly as focused as a laser and as logical as a computer. He also had a fascinating way of looking at mathematics. He had a phrase, “My equation is smarter than I am.” He really did think that a good equation could be more intelligent than its creator. There’s a kind of mysticism in that. In the last 15 or 20 years of his life, he became obsessed with the philosophy that, for a piece of mathematics to be useful in fundamental physics, it must be beautiful. For instance, he thought the theory of photon and electron interactions—what we call quantum electrodynamics—was ugly, so he wouldn’t accept it. He had this extremely rigorous sense of beauty, and saw each successive revolution in physics progressing through increasingly beautiful mathematics.
Dirac, to his dying breath, pursued this quest for mathematical beauty. For him, everything apart from that principle was just details. The job of the fundamental theorist was to look for mathematically beautiful laws. That’s why the string theorists are on the right track, even though there aren’t experiments to bear them out at the moment.
Seed: So Dirac would be a fan of string theory, you think?
GF: Well, when people get old, they tend to basically think that everything’s gone to the dogs, and there was an element to that in Dirac, who took virtually no interest in the latest findings in his field. But if you apply his idea about sticking to mathematically beautiful generalizations of past theories and to hell with experiments in the short term, then this philosophy should embolden string theorists, yes.
Originally published September 15, 2009
Page 2 of 2