Feynman's Rainbow Read online

  Today, we have quantum versions of the old classical theories, such as quantum electrodynamics, and we also have new quantum theories describing forces not even known in Planck’s day, such as quantum chromodynamics. But there is one exception to this trend of quantumization: the theory of gravity. No one has ever figured out how to incorporate the quantum hypothesis into Einstein’s theory of gravity, called general relativity.

  Quantum mechanics makes for a fascinating world. I was naturally curious about it, but I had always found textbook descriptions dry and technical. Feynman made it wondrous and magical. I was riveted. I wanted to read more.

  There were three other books by Feynman in the collection—his three-volume The Feynman Lectures on Physics, from a college survey course he gave at Caltech. They included a picture of the author—an action shot of a happy fellow playing bongo drums. Those books were unlike any textbooks I’d ever seen. They were chatty; they were amusing; it felt as if Feynman was in the room speaking to you. The discussion of mechanics spoke of Newton, but also Dennis the Menace. The section on the kinetic theory of gases included questions like, “Why do we deal with this subject now at all?” The chapters on light included a digression on “some very interesting things (which) have been discovered about the vision of the bee.” But Feynman didn’t just make physics sound fascinating. Without ever saying so, he also made it sound important. As if a physicist, with an idea, could single-handedly change the world, and the way people view it. I found myself thinking over problems and issues from Feynman’s books as I drove the tractor hauling chicken eggs, herded cattle, or peeled potatoes in the communal kitchen.

  By the time I landed back home in Chicago that summer, I had decided I wanted to study physics.

  In view of its great impact on me, the kibbutz had allowed me to keep The Character of Physical Law, in exchange for a pair of old blue jeans. Toward the end of Feynman’s book, I underlined a passage: “We are very lucky to live in an age in which we are still making discoveries. It is like the discovery of America—you only discover it once. The age in which we live is the age in which we are discovering the fundamental laws of nature, and that day will never come again.” I promised myself that I would someday make a discovery. And that I would someday meet this Professor Feynman.

  III

  FALL 1981. A lot had happened since my days in Israel. I had added a major in physics, graduated, gone to graduate school at Berkeley, and obtained my Ph.D. My parents came to the graduation. It was the last major event of my life in which we would be together as a family. It was the end of my childhood.

  Due to some formalities regarding my dissertation—namely, writing it—I arrived at Caltech well after the start of the term. As a private college Caltech had escaped the budget cuts Ronald Reagan had imposed on state schools, especially Berkeley, before he himself graduated from governor to president. Caltech enjoyed one of the highest per capita endowments of any college in the nation. It showed. The campus was beautiful, and serene. And it was large, considering that Caltech undergraduates numbered only in the hundreds. Most of it lay on a site several blocks on each side that was not intruded upon by city streets. Instead, broad sidewalks punctuated by well-kept lawns, shrubbery, and craggy gray olive trees wound their way amongst the low buildings, many of Mediterranean-style architecture. It was a place to feel peaceful and protected, free to forget the outside world and focus on pursuing your ideas.

  I felt that to have a job—any job—in academic physics was a privilege. People sometimes scoffed at academia because of the relatively low pay. But I had seen too many “adults” work too many hours at jobs they did not like in order to amass things they only thought they needed, and then, decades later, regret their “wasted” years. And I had seen my father work long, arduous hours just to make ends meet. I had vowed to have a better life than that. The most valuable asset I figured I could earn was the ability to spend my time doing something I liked.

  At first I was ecstatic that not only did I have an academic job, but it was at an elite university—the home of my hero Feynman. And it was a dream job, a particularly prestigious multiyear fellowship with complete academic freedom. But as my start date came nearer, the ecstasy dissolved and a strange thought began to crystallize: These people at Caltech might actually expect something of me. Before my dissertation had been officially accepted, I was just a promising student. My assignment was to ask questions, learn, and make the naïve mistakes that cause professors to smile and remember their own carefree days of youth. Now suddenly I was on the faculty. Students would be coming to me for wisdom. Famous professors would mutter something at the water cooler and expect an intelligent reply. Editors at prestigious physics journals would be holding spots open for articles describing my latest momentous discovery.

  I formulated a strategy to keep the pressure off: Keep expectations low, stay unnoticed, and, I hoped, discover that except for a couple of Feynman types, everybody at Caltech was as ordinary as I was.

  On my first day, I was called into the department chairman’s office. At Caltech they grouped the departments of physics, mathematics, and astronomy into one division, so this guy was really the head of all three departments. I didn’t see why a person so high up would need to see a guy like me. All I could think of was that I was being called in because they realized they had given me the fellowship by mistake. I’m sorry, I pictured him saying, my secretary sent the offer letter to the wrong guy. We meant to hire a fellow named Leonard M. Lodinow, not Leonard Mlodinow. You must know of him, Dr. Lodinow from Harvard? Anyway, it was an easy mistake, you must admit. In my daydream, I admitted it, and started looking for another job.

  When I got to the chairman’s office I found a middle-aged man, balding, holding a cigarette in his fingers. I later heard he had ulcers. He smiled, stood, and waved me in. The smoke from his cigarette left a wispy trail in the air. He spoke with an authoritative voice and a German accent.

  “Dr. Mlodinow, welcome. Things all finished up in Berkeley? We’ve been looking forward to your arrival.” We shook hands and took seats.

  I knew his comment was meant to be encouraging, but having the head of physics, mathematics, and astronomy personally looking forward to my arrival didn’t quite fit my strategy of lying low. On the other hand, at least he wasn’t telling me the fellowship was a mistake. I tried to act pleasant as my stomach tightened even further.

  “How do you like southern California so far?” He leaned back in his chair.

  “I haven’t seen much of it yet,” I said.

  “Of course not. You just got here. How about the campus? Been to the Athenaeum yet?”

  “I had lunch there today.” Actually for me it had been breakfast. I worked late and slept late in those days.

  The Athenaeum was the faculty club, a fifty-year-old building done in what I was told was the campus’s “Spanish Renaissance style.” Inside, there was a lot of fine wood, velvet curtains, and elaborately painted ceilings. I heard that upstairs there were a few guest-rooms. I thought it felt like a fine resort, but I wasn’t sure, never having been to a fine resort.

  “Did you know Einstein stayed there for two winters before he settled in Princeton?”

  I shook my head.

  “Some say he only settled in Princeton because we refused to give a staff position to his assistant. If I had been around we wouldn’t have made that mistake.” He chuckled.

  We made a little small talk. His secretary came in with a phone message, and he told her no messages until we were finished. He studied me for a moment.

  “Let me guess. You’re wondering what you’re doing here?”

  Did he see right through me?

  “I guess because people liked my graduate work?”

  “No, not here at Caltech. Here in my office.”

  “Oh . . . actually, yeah, I was wondering . . .”

  “I’ll tell you why. I asked you here because you have a special position at Caltech, and because Caltech is a special
place. That means that you deserve a special welcome, a personal welcome, from me.”

  To someone else his welcome might have sounded like a friendly gesture. But I couldn’t help thinking there was an implied and remember, just in case we’re wrong, I’ll be watching at the end of his sentence.

  “Oh . . .” I muttered. “Thanks.”

  He took a hit from the cigarette and leaned back in his chair.

  “How much do you know about Caltech?” he said.

  I shrugged. “I know the physics department.”

  “Of course, and just down the hall from your office, as I’m sure you’ve noticed, are the twin titans of physics, Dick Feynman and Murray Gell-Mann.”

  Actually this was news to me. I hadn’t yet been shown my office.

  “But you’ll find as you explore our campus further that Caltech has a rich history you might not be fully aware of. Oh, you probably know that it was here that Linus Pauling discovered the nature of the chemical bond. But did you know that it was at Caltech that Charles Richter and Beno Gutenberg invented the Richter scale? Or where computer pioneer Gordon Moore received his Ph.D.?”

  “No, I didn’t.”

  “It was. And I’m sure that, as a physicist, you know that it was here that antimatter was discovered. But you might not know it was at Caltech where the principles of modern aviation were conceived, and where the age of the earth was first accurately determined. Or that it was here where Roger Sperry figured out that the right and left hemispheres of the brain have different functions—left for language, right for visual and spatial functions. It was also at Caltech that molecular biology was practically invented. One of the key people in that was Max Delbrück, a physicist like yourself. For this, in 1969, he got the Nobel Prize.”

  He chuckled again. I didn’t see any humor in the conversation, but I tried to chuckle back.

  “Do you know how many Nobel Prizes have been received by members of the Caltech community?”

  I shook my head. I’d never thought about it.

  “Nineteen. By comparison, MIT, which is roughly five times our size, boasts only twenty.”

  I wondered if they also kept track of how many members of the Caltech community were dismal failures.

  “Why am I telling you this? Because even as we speak, the great triumphs of the future are going on today. Explore. Learn what people are doing. You’ll be surprised—and, I hope, stimulated. Beginning today, you, too, are a part of our great intellectual tradition.”

  If I had felt the least bit comfortable before, this trip down the memory lane of genius had definitely made me carsick. I wanted to tell him it sounded as if I had six months to prove myself, and then it would be all over. But I didn’t think this was quite the right time and place to open up. So what I said was: “I’ll try to live up to it.”

  He accepted my hopeless wish with great enthusiasm. “Oh, we think you will! That’s why we offered you the fellowship we did. Most postdoctoral fellows come here to work under the supervision of a specific professor. Not you. You, Dr. Mlodinow, are a free agent. You are accountable to no one but yourself. You may choose to teach if you wish, which most postdocs cannot, or you may choose not to teach. You may conduct research in physics, or, like Max Delbrück, in biology, or in any other field you wish. If you want, you can use your time to design sailboats! It is all up to you! We give you this freedom because we have judged you to be the best of the best, and we have confidence that, given the freedom, you will do great things.”

  His pep talk was heartfelt, and he was good at it. But I was the wrong subject. I left his office feeling as I did in a dream I once had. I was in an elevator going up, on my way to my office at Berkeley, when I suddenly realized that I was naked—I had forgotten to put my clothes on that morning. So there I was with a choice: push the stop button, which would delay my having to get out, but set off the alarm and call attention to myself. Or wait for the door to open and try to get to my desk without anyone noticing. In life, as in my dream, I chose the latter.

  Some days later I was in my office pondering my plight when I was suddenly offered the opportunity to deaden my nerves with champagne. The whole campus was celebrating, as it had been announced that for his split-brain research Roger Sperry had just won the 1981 Nobel Prize in Physiology or Medicine. In Nobel laureates, Caltech and MIT were now tied. One hemisphere of my brain was proud and excited to be in the midst of this, the other disquieted, as if the pressure had just been turned up a notch.

  IV

  WHEN I WAS FINALLY shown my office, it turned out to be right next door to that of Murray Gell-Mann—one of the twin titans the department chair had mentioned. Some days later I introduced myself and we talked a little over the tea and cookies table that was where people went after a seminar. Murray looked exactly as I had expected from the pictures I had seen—right down to his trademark bolo tie. I told him my name. He didn’t tell me his—when you are that famous why bother—but he did repeat mine. It was unrecognizable to me, but, he told me, it was the “correct” (Russian) pronunciation. He also gave the etymology. I didn’t ask him the origin of his own unusual name; it turned out the hyphen was his father’s invention. Almost everyone called him by his first name, anyway. Feynman was “Dick” to a much smaller group.

  Murray’s ideas had dominated physics for over twenty years, but his most famous achievement was to invent, in the 1960s, an elegant mathematical system for classifying and explaining the properties of the dozens of known subnuclear particles. Except for the more traditional nuclear components—protons and neutrons—these subnuclear particles decayed within a small fraction of a second, and had been discovered in the last few decades. They came into existence only when, for instance, protons were smashed together. To account for the mathematical order he found amongst this zoo of subnuclear particles, Murray later proposed that the proton, neutron, and the other particles had an internal structure, being made of different combinations of just a few more basic building blocks. These were “sub-subnuclear particles”—that is, particles within the particles that make up the nucleus. He dubbed them quarks. Individual quarks have never been seen, but eventually physicists grew to accept Murray’s theory. This has earned him comparisons with Dmitri Mendeleev, who invented the Periodic Table of Elements. Like Murray’s system, the Periodic Table organizes the chemical elements into groups based on common properties. And like Murray’s system, this order amongst the elements was eventually explained in terms of an internal structure—in this case, the atom’s internal structure of particles later named electrons.

  Murray’s work won him a Nobel Prize and helped him to become one of the most influential scientists of the postwar era. Yet he appeared to have an inferiority complex and seemed anxious to show off how brilliant he was. It didn’t matter if you talked about particle accelerators or septic tanks, he could and would tell you how they work, the crucial specs, and what to look for in the latest model. His conspicuously “correct” pronunciation of my name was no aberration; he seemed to seek opportunities to say foreign words, such as the names of cities, so that he could show off his ability to pronounce them like a native. One moment you’d be listening to a seemingly normal native New Yorker, then suddenly his face would contort and for the next few words he would be Quebecois, or Russian, or Chinese. Once, a student who had learned a few words of Mayan while on holiday decided to test Murray’s claim that he knew that language by uttering a sentence for Murray to translate. Murray reproached him. The student’s sentence was in Lower Mayan. The language Murray said he knew was Upper Mayan.

  Feynman and Murray were, at least off-and-on, friends. It was to be with Feynman that Murray chose Caltech over other universities that had made him offers. And it was Feynman who, in the late 1960s, provided some key theoretical evidence regarding Murray’s quarks, supposedly inside every neutron and proton but never seen in isolation.

  At the time, it was a major controversy in physics: If we can’t isolate an individual quark
, what sense does it make to say that individual quarks really exist? Aren’t these particles within particles merely a convenient mathematical construct? These questions are part of a greater philosophical issue: To what extent are the results of experiments in modern accelerators direct observations, and to what extent are they merely agreed-upon interpretation of numerical data? After all, even ordinary particles such as electrons and protons are thought of as having been “observed” even though we “see” them only through such indirect evidence as the tracings of their path on film, or the clicks of a Geiger counter. And for more exotic particles the evidence is even less direct: They are inferred to exist from statistical blips on charts of data pertaining to the scattering of other particles. Might not a civilization on Mars, making the same experimental observations, have a completely different concept of the “reality” that underlies them? One school of philosophy, called positivism, avoids these issues by holding that only what we can sense directly can be accepted as reality. Modern physics has ventured far beyond the positivist point of view. But for many, the idea that an unobservable particle like a quark was real was pushing the envelope a little too far. When confronted with such issues, Feynman would say he had doctor’s orders not to discuss metaphysics. Yet it was he who, in the late sixties, published work showing how certain experimental observations of proton behavior could be explained by assuming that protons had an internal structure of unseen subparticles—the kind of indirect “observation” of quarks that most physicists accepted as proof of their existence. Ironically, Feynman, ever the cynic, begged to disagree. Quarks had many special properties that were not relevant to the physical process he had investigated. Thus one could not conclude from his calculations that the unseen particles of his theory had those properties, that is, they were actually quarks. It could have been that Murray’s theory was wrong, and that other, yet to be characterized, unseen particles existed within the proton. Because of this, Feynman refused to dub the internal particles of his theory quarks, and called them, instead “partons.” This annoyed Murray, partly because of the refusal to endorse his work, and partly because the word parton is a mixture of Latin and Greek roots. But that was Feynman: fastidious about describing nature, cavalier about the rules for mixing Latin and Greek.