I admired him for something else, too. Schwarz, like me, had gone to Berkeley. His Ph.D. advisor there, in the sixties, was a fellow named Geoffrey Chew, who was the leading figure behind another very ambitious approach called S-matrix theory. The aims and philosophy behind S-matrix theory were similar to those behind string theory, and for a few years it was the hottest thing around, but it didn’t pan out. Chew, however, didn’t drop it, and for decades he worked, like Schwarz, snickered at and virtually alone. Chew got nowhere and ended his once brilliant career in oblivion. For Schwarz to work in Chew’s shadow, to seem to be repeating his history, and still to move forward smiling, I thought, showed great character.
I knew Ray wouldn’t understand a word of the seminar, which would put him only slightly behind me, but I figured since he kept asking what it was we really do all day, I might as well give him a taste of it.
Only about ten people, half of whom were Schwarz’s graduate students, showed up for the talk. But shortly before the talk began, joining the group loitering outside the seminar room were both Murray and Feynman. It was the first time I had seen them both attend a seminar, and I figured it could mean fireworks.
Some years earlier, when it was more common to see Feynman and Murray both attend, seminars at Caltech had the reputation of being brutal events. Murray might challenge you incessantly, even on the tiniest point. Or worse, if he thought what you were saying was of little importance or interest, he might pull out a newspaper, and read it in conspicuous boredom. Feynman, too, was always brash and unwilling to accept wrong or sloppy thinking, and he seemed to revel in playing cat-and-mouse. To Feynman physics was a show, and if you didn’t satisfy him with your answers his response was sometimes to get up, announce his opinion, and march out of the room. The combination of Murray and Feynman was so intimidating that at least one future Nobel Prize winner hesitated to lecture at Caltech.
As we walked over Murray was speaking to a visitor who apparently had just come from Montreal. Only Murray insisted on pronouncing the city’s name as the natives did, “Mon-ray-al.”
Feynman turned to face Murray. “Where?” he said.
“Mon-ray-al,” repeated Murray.
“Where’s that?” said Feynman. “I’ve never heard of Mon-ray-al.” He exaggerated Murray’s pronunciation for effect.
“I’ve observed that there are many well-known cities whose names you don’t seem to recognize,” said Murray.
“Logically speaking, that means that either I’m an ignoramus . . . or you say them in a funny way.”
“Not true,” said Murray. “Logically speaking, it could also be both.” Murray was always a stickler for precision.
Feynman smiled. “Well, we’ll just have to let everyone draw their own conclusions.”
Murray smirked and walked into the seminar room. Feynman found teasing Murray to be fun and games; Murray always let it upset him. I quietly pointed Feynman out to Ray.
“Who was the other one?” he said.
“Murray Gell-Mann.”
“Oh, the quarks guy.”
“Yeah, the quarks guy.”
“Do they always talk to each other like that?” he asked.
I shrugged. I rarely saw them together.
“They remind me of my mother and father,” Ray said.
As the seminar began Feynman yelled out, “Hey Schwarz, how many dimensions are you in today?”
It wasn’t the only time I heard him utter that gibe, referring to the extra dimensions required by string theory. But it was always good-natured. This meant something, because Feynman’s quips did not always possess that quality. So I didn’t feel it necessarily showed where he stood on the subject. I felt a little tense, standing there, waiting with Ray. I was ready to watch a fight—would Feynman and Murray team up against Schwarz, or would they end up somehow battling each other? I was a little embarrassed to have brought Ray, the way you might be embarrassed to have a friend hear your parents argue.
Schwarz smiled and began his talk. He seemed at ease. He even wove in a few jokes. They received hardly a chuckle. Years later Schwarz would tell me with amusement how, after he became famous, similar quips would bring roars of laughter.
Feynman and Murray listened respectfully, and asked only a few technical questions. There were no derisive comments.
A few minutes into the talk I looked over at Ray. He was asleep.
At the tea and cookies in the back of the room after the lecture I introduced Ray to Feynman. I had warned Ray not to be too aggressive. And for God’s sake not to ask questions of a psychological or metaphysical nature. Feynman has doctor’s orders not to discuss metaphysics, I had told him. He had given me a weird look, but I was confident he’d be on his best behavior. Feynman turned to me.
“So, did the seminar teach you anything useful about that ‘nonsense’ theory you were interested in?” he said.
“You mean you knew all along it was string theory?”
“It’s the only nonsense theory we’ve got going in this department,” he said.
“If the theory is nonsense,” Ray asked, “why are you here?”
Feynman grinned. “I came for the cookies.”
We drifted into the corridor outside the seminar room. At that point the visitor from Montreal, who had been eavesdropping, stepped over.
“I don’t think we should discourage young people from investigating new theories just because they are not accepted by the physics establishment,” he said.
Something about his challenging tone made me feel this guy would be at home addressing a Berkeley rally against cultural imperialism. But Feynman took it well.
“I’m not telling him not to work on something new,” Feynman said. Then he looked at me and said, “I’m just saying, whatever you choose to work on, be your own worst critic. And then don’t do it for the wrong reasons. Don’t do it unless you really believe. Because if it doesn’t work out, you could end up wasting a lot of time.”
The visitor said, “Well, I have been working on my own theory for twelve years.”
Feynman asked him what theory that was. The man described it briefly. He seemed peeved at the end that no one was impressed. I felt that just for listening politely we should have all been awarded a prize from the give-dumb-theories-equal-time movement, of which I was certain he must have been a member. He seemed to sense this, for he added, “It took the physics community years to accept Einstein. It is taking them years to accept Schwarz. I don’t mind if it takes them years to accept my work. It’s really a compliment. And it’ll make it all the sweeter when recognition does come.”
I didn’t think the fellow’s attitude would go over well with Feynman, but he seemed to be listening intently. And when the fellow finished, Feynman nodded politely, as if he had just learned something.
Then he looked over at me and said, “That’s exactly what I mean about wasting your time.”
The visitor walked away in a huff. Ray said to Feynman, “How could you say that to him, man? That’s cold.”
I elbowed Ray.
Feynman said, “You don’t like what I told him? Why not? He wanted recognition. I gave it to him. I recognized him as a pompous ass.”
Just then Helen appeared down the hall. She was holding some mail, apparently Feynman’s. She made a gesture that I took to mean she would leave it in his office. He nodded. Then, spotting me, she called me over. I gave Ray a warning look that said, “Watch what you say!” He gave me a look back that said, “Moi?” I was worried about exposing Feynman to Ray untended, but, when Helen called, you obeyed.
When I finally got back from her office around the bend, the corridor was deserted and Ray and a few butter cookies was all that was left in the seminar room.
“How did it go?” I asked. “Will he ever speak to me again?”
“Relax,” he said. And then, “You need some pot.”
“Ray, shut up!” I looked around to be sure no one was within earshot. What I didn’t know at the time was
that Feynman had himself tried marijuana—and even LSD.
“Don’t worry, it went fine. We’re buddies. Hey, you never told me he had a Nobel Prize.”
“He told you that?”
“Yeah.”
“I heard he never talks about that. He thinks the Nobel Prize is by its nature unfair. And a big distraction. A false God, so to speak. He told me when the first reporter called him in the middle of the night to tell him he had won it, he told him to call back at a decent time and hung up.”
“Well, maybe he feels that way. But maybe he’s also proud. That would be human, wouldn’t it? Maybe he just doesn’t open up to you like he does to me.”
“So now you and he are best buddies, I suppose.”
“Well, you know what else he told me? He finally explained to me what you physicists all do, and why you do it.”
“He did?”
“He did.”
“What did he say?”
“No, no, no,” he said. “You don’t get off that easy. Ask him yourself. Or even better, find your own answer.”
“Now you sound like Feynman,” I said.
“Well, we did see eye to eye on certain things.”
I let it go at that. But I figured, one way or another, I’d get it out of Feynman.
XIII
IN 1988 A FORMER CLASSMATE of mine from Berkeley started writing a text on string theory that is now a standard reference for physics graduate students. He projected completing the book a year later in June 1989, “plus or minus one month.” It is not uncommon that books are finished late, but this book wasn’t published until 1998. It had taken eleven years, over ten times the projected period. Why? String theory is hard. There are famous stories about how few people understood relativity and quantum theory in the early days, and even in more recent ones. But it is safe to say that, even today, nobody understands string theory.
Most new theories are demanded by nature. They grow out of new physical principles or experimental facts that need to be explained or accommodated. String theory did not arise that way. String theory was like penicillin, uncovered by accident. Theoretical physicists are still searching for the new physical principle string theory presumably represents. Experimental physicists are still searching for an experimental consequence they can test in the lab. Physicists who study it are like paleontologists, patiently digging and scraping at it, as if they are uncovering a giant skeleton of unknown origin.
It all began in the summer of 1967. Murray, who hadn’t yet received his Nobel Prize, was giving a lecture at the Centro Ettore Majorana in Erice, Sicily. He was speaking about some issues in S-matrix theory, that theory championed by Schwarz’s Ph.D. advisor, Geoffrey Chew. That theory that never panned out. In the audience was an Italian graduate student (then working in Israel) named Gabriele Veneziano. Murray, ever the classifier, ever the Greek, was discussing some striking regularities in data pertaining to the collisions of protons and neutrons. Veneziano was intrigued. It took him a year, but he eventually found a simple mathematical function that magically described the regularities. The word magical here is not used cavalierly: Veneziano did not employ any theory of physics to derive the function; he simply discovered the mathematics that worked. It took a couple more years for physicists to propose a reason why it worked. The why was first presented in 1970, in the work of Nambu and Susskind, who figured out that Veneziano’s mathematical function would arise from the underlying theory if you modeled the protons and neutrons, not as point particles, but as tiny, vibrating strings.
That seemingly simple idea, it turned out, was far richer, and far harder to implement mathematically, than anyone might have guessed at the time. And though it was a physical model of what particles are made of, it wasn’t a physical principle, like the constancy of the speed of light, that could guide you in your thinking as you sorted through all the possible ways to develop the theory. That’s another reason string theory is so hard.
After my two attempts at gently raising the issue of string theory, one afternoon I stepped into Feynman’s office to ask him what he really thought.
“Can we talk a little about string theory?” I asked.
“I don’t want to talk about string theory. I don’t know much about it.” He looked back down at his work. “You wanna talk about string theory, go talk to Schwarz.”
“I did.”
“Then go talk some more. I’m working.”
“It’s hard to understand, and I’m trying to decide if it is worth the effort.”
“Like I told you, only you can decide that.”
“Don’t you think there are aspects of it that seem very promising?”
“Promising? What does it promise? Does it promise to tell you the mass of the proton? No. What does it promise to tell you?”
“Well, no one knows how to extract any quantitative predictions yet, but—”
“You’re wrong. It does make a quantitative prediction. Do you know what that is?”
I looked at him. My mind was a blank.
“It requires that we live in ten dimensions. Is it reasonable to have a theory that requires ten dimensions? No. Do we see those dimensions? No. So it rolls them up into tiny balls or cylinders too small to detect. So the only prediction it makes is one that has to be explained away because it doesn’t fit with observation.”
“I know . . . there’s a lot to be worked out. But what intrigues me is that string theory has the potential to unify all known forces of physics into one theory. Even gravity.”
He looked at me with a strange expression. The kind you might expect if you were making small talk with a Catholic bishop and casually inquired about his wife and kids.
“A unified field theory. Isn’t that what we all want?” I said.
“I don’t want anything. Nature has nothing to do with what I want! How do you know there’s one unified theory? Maybe there’s four theories! Maybe there’s a theory for each force! I don’t know. I don’t tell nature what to do. Nature tells me. This whole discussion is pointless! It’s getting on my nerves! I told you—I don’t want to talk about string theory!”
This last part got loud. Plus he was waving his arms. I was taken aback. First, because I thought the reason we all did physics was our passion for the beauty and elegance of nature, and four theories didn’t seem very elegant to me. And second because from the expression on his face, I was afraid he might get up and bite me. I figured it was time to make my exit.
“Look, I’m sorry. I just wanted to get your take on it.”
“My take? My take is that you hit a dry spell, and now you’re scrambling, trying to find something to work on.”
“Is that wrong?” I asked.
“What’s wrong is coming to me to talk string theory.”
“Your opinion matters to me.”
“Like I told you before, what should matter to you isn’t my opinion. It’s your opinion.”
“I’m sorry I bothered you,” I said, and started to leave.
“Look,” he said, “selecting a research problem isn’t like climbing a mountain. You don’t do it just because it is there. If you really believed in string theory, you wouldn’t come here asking me. You’d come here telling me.”
I felt like a little kid who had just been scolded by his dad. Back in the corridor, I got scolded again, by Mom. I ran into Helen. Though she was the secretary for the entire floor, she worked mainly for Feynman and Murray. A thin, middle-aged woman, she had the grit to stand up to both of them, and tons more grit than she needed to handle me. She was sporting a major frown.
“What did you say to piss off Professor Feynman?” she asked.
I shrugged.
“You know you shouldn’t interrupt him when he is working.”
“I guess I just tried to engage him on the wrong topic.”
“Philosophy?” she asked.
“No, string theory,” I said.
“Oh, God, that’s just as bad.”
“Can I ask you a
question?” I said.
“Maybe,” she said. “What is it?”
“If everyone is so skeptical about Schwarz’s work, why is he still here after nine years?”
She gave me a look. I didn’t know if she meant, “You mean you don’t know?” or “Why do you care?” But after a moment, she said, in a lower voice, “He has someone who looks out for him.”
“Oh? Who’s that?” I said.
She said, “Murray.”
XIV
A COUPLE OF DAYS afterward I was at the office late in the day. Earlier, Constantine had told me that Murray had been estranged for years from his daughter, who had joined what became the Marxist-Leninist party of the U.S.A., and was a big fan of Albania. Apparently, although Murray derided Reagan by calling him Ray-gun, Lisa had crossed a line by singing songs like “Down with Ronald Reagan, Chieftain of Capitalist Reaction!”
I sat at my desk thinking there were ironic parallels with Lisa’s politics and Murray’s underground support for Schwarz’s subversive theory. For in their own way, Lisa’s politics were not any farther from the mainstream than string theory, or for that matter, than Murray’s earlier discovery/invention of fractionally charged quarks.
Did daughter inherit from father the ability, for theory’s sake, to be unmoved by seemingly obvious data—like the absence in our world of string theory’s extra dimensions, or the absence in Albania of certain amenities, like food, clothing, and shelter? Did they share a genius (or curse) of being able to see through the façade of reality to a more fundamental truth?
My ruminations were interrupted by Murray, whom I could once again hear yelling through the wall. It was disquieting, but that didn’t bother me, for my office, anyway, was far too quiet for my taste. What did bother me, with communism still fresh on my mind, was the thought of the poor downtrodden individual on the receiving end of his tirade. I decided if Helen could bring it up to him, so could I. I would tell him a thing or two.
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