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Courtesy of AIP Emilio Segrè Visual Archives
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Interview of Gino Segrè by [David Zierler on May 8, 2020,Niels Bohr Library & Archives, American Institute of Physics,College Park, MD USA,www.aip.org/history-programs/niels-bohr-library/oral-histories/XXXX
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In this interview, David Zierler, Oral Historian for AIP, interviews Gino Segrè, emeritus professor of physics and astronomy at the University of Pennsylvania. Segrè recounts his childhood in Italy and his family’s abrupt exit for the United State before the outbreak of World War II. He discusses his life in New York, and his family’s decision move back and forth from Italy. Segrè discusses his undergraduate experience at Harvard and his graduate research at MIT. He discusses his work on field theory at Berkeley, and his decision to join the faculty at Penn where he set about helping to build up the elementary particle physics program. Toward the end of the interview, Segrè discusses his developing interests as a science writer, the present course of theoretical particle physics and the importance for physicists to reinvent themselves over the course of their careers.
Okay. This is David Zierler, oral historian for the American Institute of Physics. It is May 8th, 2020. It's my great pleasure to be here with Professor Gino Segrè. Gino, thank you so much for being with me today.
A pleasure. Thanks, David.
Okay, so to start, tell me your title and institutional affiliation.
Sure. I'm an emeritus professor of physics and astronomy at the University of Pennsylvania in Philadelphia.
Wonderful. And now let's go right back to the beginning. Before World War II, tell me about your birthplace, and your family background, and your early childhood in Italy, and then of course, coming to the United States shortly after you were born.
I was born in Florence, Italy in October 1938. My father is an Italian Jew and my mother is a German Catholic. My father was a university professor, and the anti-Semitic laws had been passed in Italy in the summer of 1938, just before I was born, and so he was suspended from the university. And it began to look like it would be a good thing to get out of Italy. So we left Italy in May of 1939 with a visitor's visa, supposedly just to go see the New York Worlds Fair, which had started in April 1939. We of course had round-trip tickets on the Rex, the [laughs] flagship of the Italian steamship company. Once we got to New York, we looked around, as did many other immigrants, for ways to convert these visitors visas into long-term visas, permanent residence visas, and it appeared that the way to do so was to leave the United States temporarily, go someplace nearby, and then re-enter. Lots of people did this in different ways. I have an uncle who was then in California. He went to Mexicali in Mexico. I know other people went to Canada. We went to Cuba. And so we re-entered with visas from Cuba. As I like to say, "Ah, the old days in Havana." Back in 1939.
[laughs] Now, I'm curious, I don't know if you ever talked to your par-- Obviously, you were too young for this, but in terms of your parents sensing what was going on in 1938, did your father, did he think that if they had not gotten out, it would have been a matter of life and death at that point?
Well, he had spent a few years in Germany. But he had a very positive view of Germany as a very educated, civilized place. But my mother, who had come from a working class German family, said to him, "You don't know what Germany is like."
"And you have a distorted image of this. And I think it's a good idea to leave." So--
And what language did they speak to each other in?
Primarily in Italian. They had met in the early 20s, and they had come together to Italy around 1923. So my father preferred Italian. But they would sometimes speak in German. But it was, you know, one of those decisions. Other people didn't. For instance, my father was one of three brothers. One of whom was a physicist, and the physicist had left--
Emilio gone to-- in 1938, to Berkeley. Even though it was a demotion, because he had been a professor in Italy. At Berkeley, he was a research associate. But the third brother, Marco, for instance, stayed in Italy. And I think, you know, it was right in the balance of those kind of judgments, and I think Marco was married to another Italian. And Italian women had strong ties to their family. My mother had no such ties So I think that's what made it easier for us to leave.
Did you have any family in New York?
No. My father was one of many émigrés,. He had been a professor of ancient history. But humanities professors from Europe in New York at that time were a glut on the market. And he got some sort of research associateship at Columbia for a while.
And where did the family live? In Manhattan?
We lived on Morningside Drive. Now, sometimes known as Morningside Heights, because that was the connection to Columbia and knew a few people there. I mean, if you want illustrious example, Enrico Fermi had moved to Columbia in, well he did it in a classy way. He got the Nobel Prize in 1938 and came straight from Stockholm to the United States. His wife was Jewish, so that's why they left. I mean, he wanted to leave because he was interested in physics. And physics was much better in Italy. And his wife was Jewish. So that combination, it was again, a husband wanting to go and a wife who was Jewish. So he went to Columbia, but they lived around that area. On Morningside Heights. At least at first. So it was, you know, gemütlich, as we used to say.
As far as those things go.
Do you have a memory of New York? When you were a kid?
Yes, I do. I lived there until I was almost nine. So it's childhood memories, you know. Playing around Morningside Drive, listening to the radio, collecting... My parents managed to get me a war surplus helmet, which I wore proudly. You know, those kind of typical childhood memories.
Now, when the decision to move back to Italy came, was that the plan from the beginning, to go back as soon as the war was over? Or was there consideration to stay in America?
When I was born, my mother was 40 and my father was 48. My observation is, the people who immigrated to the United States, younger than 35, let's say, you started life over again. Or else, if you were older but had a kind of position, a job, that was much desired in the United States, if you were 45 or 50, and didn't have something, a really good position in the United States, then you thought, if you could, you kind of wanted to go back to Europe. But so we went back in 1947. But we were hedging our bets, in the sense that Italy had then a very large Communist party, Socialist party, and in fact, general elections were held in the spring of 1948. And there was a strong possibility that Italy would go leftist, or at least my parents thought so. So they wanted to hold on to their United States citizenship, in case Italy became another Yugoslavia.
So we went back and stayed the first time until 1950. At that point, things were looking pretty good. I have an older brother, he was in high school, I was in 6th grade. My parents were reasonably happy back in Italy. But their passports expired after three years. So we all went back in the summer of 1950, and I suspect the idea was to renew our passports and go back to Italy. But at that time, I don't know how much politics that you-- Do you want to keep on going on the politics?
Absolutely. This is great.
Okay. At that time, the United States had sort of swung rightward. And you know, it's the Cold War then.
McCarthy, McCarran, Senator McCarran had a strong influence on the passport office. And the passport office said, "Hey, you know, what is this business of your wanting to go back to Italy right away? You ought to prove that you love America by staying here." So we didn't get passports back for two years. At that point, my parents decided, "Hmmm. Yes, we want to hold on to our American citizenship, but we also want to go back to Italy." So they embarked on this strange way of living, of six months in the United States, or rather six months and two days in the United States, and five months and 28 days in Italy. And that's what we did. That's what they did, including me, and my brother was then in college. That's what they did for the next ten years.
What impact did this have on you, going back and forth trying to grow up and make a name for yourself?
Well, my parents were eccentric. Let's put it that way, okay? So for instance, when they found that they couldn't get their passports, they decided, "Well, maybe we should move out of New York City."
Oh, Gino, I want to stop you for a second. When you move the computer on your lap, that picks up on the speaker very loudly, so it's hard to hear you.
Okay. So then my uncle, this is my uncle Emilio, who was by then a fairly prominent physicist. He had been at Los Alamos. And he said, "You know, they might drop an atom bomb on New York City. Maybe you should move out of the city." So my parents, who as I said earlier were somewhat eccentric, got on a train and we all moved 40 miles up the Hudson to Peekskill. A town where they didn't know anybody, and didn't have any connections. Also my parents, neither of them knew how to drive. So we got off the train in Peekskill, walked up the hill to find a real estate agent, and bought a house in Peekskill. So--
What was the employment plan? He was going to be a professor in Peekskill?
No, no. My father had inherited some money from his father. So my father gave up ancient history, and decided to devote all his time to painting. To being an unrecognized genius. [both laugh] And my mother, who had been an artist, decided to quit painting. And to take up writing, another unrecognized genius. They basically closed in on themselves. And they also decided at that point that I should become a theoretical physicist.
They figured that out for you?
I mean, my next question is, what semblance of educational continuity could you possibly have had, going back and forth like that?
So, I'm a graduate of Peekskill High School, and what I used to do is arrive in Peekskill at Christmas. I didn't go to school in Italy because I couldn't just go there for two months. I was also hopelessly behind in Latin, which was the big subject there. So, during the fall, I sat at home with the unrecognized geniuses. And then at Christmas, we would go back to Peekskill, and Peekskill I don't mean to insult the city, but at the time, it was not a, let's put it this way, an academic peak.
I went to school in Peekskill for six months a year. I even graduated a year early. Because my 9th grade math teacher had decided, "Hey, this kid is pretty smart. Let's put him in 12th grade math and see how he does." So I did very well, so I skipped all of basically high school math and I took some regents exams.
Now I want to ask you, at this point, I mean, the fact that you have an uncle who's a prominent physicist, right? Any strength that you had, would that have been purely a genetic similarity? Did you learn from him? Were you exposed to his level of physics, you know, growing up at all?
Not at all, because he and my father quarreled. So I never saw him, really. But it was in the air, that, I mean, in Italy, you know, Italian Jews were very oriented toward becoming professors, and particular in math and the sciences. In 1910 Italian Jews were 1/10 of 1% of the Italian population. But they were 10% of the university professors. And close to 30% in math and science. So math and science were talked about as the subjects to do in Italy, at least among Italian Jews.
And then it helped, of course, my uncle at least, even though we didn't see him, he had been Fermi's first student, so that was also in the air. And Florence had been in the 20s and 30s Italy's second hotspot in physics. And my parents knew many of those physicists. So they thought physics is the thing this kid ought to do. And then there would be the added bonus, if he became a genius, then that would prove that we as unrecognized geniuses are also geniuses. [laughs]
There you go.
That's a tall order for you.
It was a tall order. So I arrived at Harvard, largely because the home economics teacher at Peekskill High School had gone to (Simmons 18:09), and said, "I knew Harvard kids when I went to Simmons, and they were really nice, very smart, and often quite a bit, a little weird. So I think you would really fit in there."
[laughs] Not to mince words.
Exactly. So I said, "Sounds good." In Florence, that early September, I packed my suitcase up, took a boat to New York, took the train to Boston, and then I was told to take a subway to Harvard Square. I landed in Harvard Square, thinking that would be the middle of the campus. Didn't see Harvard Square, but was told that, yes, it was right there, you just have to walk in that gate. So I went to Harvard. Announced to my freshman advisor that I was a genius [laughs], and would they mind putting me in advanced courses? Harvard being Harvard, it's a wonderful place in many ways, but they're not warm and fuzzy, you know?
And they don't pay much attention. So they put me in junior physics and junior math. And then--
Now, did you declare your major right away, or that took some time?
I more or less decided right away, because they also decided, since he's going to take junior physics and junior math, let's make him a sophomore.
So there I was, not quite 17 year old sophomore in junior physics and junior math. Ah. It was tough. The course in junior physics was a disaster. I didn't know how to solve any of the problems.
Do you remember who taught it?
I do. Robert V. Pound. I also remember I got a 31 in the final.
That's out of 100, I assume.
Out of 100. I think the median was 60, you know, so my grade was a C. But obviously, I was not a genius, okay, in physics. In math I did better. There were three freshmen in the class. And the other two were both better than me. Of course, as I later found out, one of them became a math professor at Berkeley and the other one became a math professor at MIT. So it wasn't so bad, but I got a B.
Did you have a sense of you know, the real luminaries in the department in those days, and did you try to avail yourself of getting to know them at all?
A little bit later on. Not quite as a freshman. You know, freshmen, you're too young.
So but after this first semester, I needed to decide. Do I take a step backward, admit that I really don't know anything much, and go back and take freshman physics and an easier math course? Or do I put my chips on the table? In for a nickel, in for dime, and go forward? And I decided I better go forward. Because going backward admits failure. Let's say this is a temporary setback, and you're going to catch up. So that's what I did.
Obviously, you recovered.
Well, my sophomore year, then, I took the lowest graduate course there was, which was an introduction to atomic physics taught by Norman Ramsey.
Ramsey's course, it turned out to be a lot easier than freshman physics. Harvard figured that once you're in graduate school there, "Hey, we've admitted you to graduate school, we aim to keep you. We're not going to make things hard for you." So--
Right. It's a very, which is a very Harvard way of looking at things.
Exactly. So, you know, it wasn't like Harvard Law School, you know, where it says, "Okay, one of three of you is going to flunk out." No, no, we're going to keep you all. So it was kind of easier. They'd ask you, on the final exam, repeat some proofs we have given you in class. I had taken notes and had a really good memory. And then they'd give you some easy problems. So I got an A in Ramsey's course.
I thought, "Hey, maybe I am a genius after all." [both laugh]
Or at least maybe you're capable of getting an A in Ramsey's course.
Exactly, you know? And then I took graduate mechanics in the spring. And there the final exam was, I'm going to give you ahead of time 20 problems. Five of these are going to be on the final. So I worked really hard, you know, and looked at all the books and everything and managed to get solutions to all 20 of them So I got another A.
You're on a roll.
I'm on a roll. So sophomore physics was looking pretty good.
I want to ask, Gino, maybe this is the right time. When did you develop your interest in science writing, in history of science? Was it this early on, or was that later?
Much, much later.
I can answer that one right away, do you want me to answer that one and then go on back?
Sure, let's talk writing for a second, but yeah, please.
No, I'd never written anything and didn't, I mean-- When I showed up at Harvard, before they made me a sophomore, there's a required writing course. And the first assignment was to write an outline. And I didn't know what an outline was. And I'd never written a paper in high school, in Peekskill High School, so I had no idea. Then when they made me a sophomore, it was considered that I had passed the freshman writing. I hadn't even learned to type, because the one course in my going back and forth to Peekskill I couldn't take was typing. Because that was a full year course. So I'd write out all my little papers at Harvard in pencil longhand. My real interest in writing took place at age 60.
Because I didn't want to become a grumpy old theoretical physicist. There were too many of them. They'd walk around and say, "You know, this department isn't friendly the way it used to be." And so I thought, "Hmm, I need an exit strategy." And then in addition, I was on some committee to discuss what it is that every Penn freshman needed to know. And there were the humanities, the social sciences, and the natural sciences people. And the humanities people said, "You know, we need to know about beauty and the Renaissance.” And the social science people would say, "We need to know about racism and elitism and so on." And I got up and said, "Well, I think it'd be a good idea if every Penn freshman had heard of the Big Bang, the beginning of the universe, the formation of the Earth's plate tectonics, and maybe about DNA." You know, beginning of the universe, beginning of the Earth, and beginning of life.
I like it.
I tried to not sound partisan by leaving physics out.
And then all my science colleagues jumped on me and said, "You know, this is all bullshit. You're talking about just having a smattering of this stuff. What they really need to know is about dissecting frogs and pulleys and all that kind of stuff." So I left the meeting, and I said, "Okay, I'm going to write a book which has in it the Big Bag, plate tectonics, and DNA." So--
Which book was that?
It was called The Matter of Degrees.
Oh, that one, okay.
So what happened was, I decided I'd better get an agent, because otherwise, what am I doing? And I'd heard John Brockman, you know? Agent of the-- You know who he is?
Okay. Agent to the science--
Stars. And I had just seen a book by Alan Guth in which he had as his agent, John Brockman. So I said, "Alan, would you drop a line to John Brockman saying I'm a real guy?" And so he did, and John Brockman had a son who was then at Penn. So John Brockman happened to be at Penn, and we had lunch together. And I pitched this book to him. And he said, "Great!" And I said, "John? Are we having lunch or are you my agent?" He says, "I can't afford to have lunch with people. I'm your agent." And I said, "Okay John, what do you want?" And he said, "I want a 5-page summary of what this book is going to be about. A 1-page outline," by then I knew what an outline meant. "And one page which says why everybody's going to want to read the book." So I said, "Okay, John. I can do that. Don't you want to see a chapter?" And he said, "No, Gino. No chapters. I sell hope. If we show them anything you've written, then there's less hope." So I got that stuff, sent it to John, and he made one correction. Because I had said, this is about the Big Bang, plate tectonics, DNA, and also quantum neutrinos and stuff. It's a set of loosely connected, intertwined passages about this. And he says, "No, no, no, not 'loosely intertwined', 'closely connected'. So I made that change. He sold it to Viking.
And they gave me an advance. And there was a wonderful editor there named Wendy Wolf, and then he sold it also to Penguin in the UK. I thought, "Hey, I'm an author. All I have to do now is write this book." And--
Now, was your intention to gear it towards the same kinds of students at Penn that you wanted to have this as a course?
No. My clientele was going to be 50 year old lawyers with insomnia. So it was called A Matter of Degrees: What Temperature Reveals about the Past and Future of Our Species, Planet, and Universe.
Okay. I'm glad you were so narrowly-focused on your first book.
Exactly. [both laugh] So it was going to be for the general reader. So over the next three years, I mean, I was still a professor at Penn. So I was still teaching. And I eased out of research at that point, and I eased into being a writer, which was great fun.
My wife, who's actually a good writer herself, was extremely helpful, including giving me the title. I mean, I'll give you an example. We needed a title, and at the time I was a great admirer of Jared Diamond's Guns, Germs, and Steel. So one day I said, "I've got the title. It's going to be: Fevers, Tubeworms, and Neutrinos." And she looked at me and she said, "Are you crazy?" And I said, "Okay, I'm very good at taking criticism. So give me a better title." And so the next day, she said, "A Matter of Degrees." So she did a lot of leavening, as we say, of this book. But by the end of the first book, I was then an author.
So being an author means you can sell your second book, you get to go to Bellagio, you know what Bellagio is?
It's a beautiful place on Lake Como, where the Rockefeller Foundation has an institute, and you are invited to go there for a month and live with other like-minded individuals in the arts and stuff.
And look down at Lake Como and eat wonderful meals. We can get to my career as a writer later, but back to Harvard and the would-be genius, okay?
So junior year, by then, I was taking the real first year graduate courses in physics. The hard ones. And they weren't that hard. So it looked like maybe I had made it, you know? But then came time to go to graduate school. And yeah, it might have been natural to stay at Harvard for graduate school, but I still really felt too young. So I went back to Harvard and I said, "Hey, can I stay an extra year?" And they said, "Sure. Whatever you want." So I stayed my fourth year, and kept thinking, "Do I really want to stay at Harvard?" Which is what many of the bright undergraduates did-- My best friend was Michael Wortis, who was a year ahead of me, and he stayed, and he had graduated summa cum laude, first in his class at Harvard, and went on to stay at Harvard. And I thought, "Gee, you know, all these Harvard people, then they go and work for Julian Schwinger I went to a couple of his lectures, and they were totally incomprehensible to me.
You're not the first to say that.
And his graduate students were all super bright, and what they would do is they would wait for him after his lecture, and Schwinger would give them a problem, and they were all very bright, and so they would write wonderful theses for him. And I thought, "You know, I don't feel like going into this. On the other hand, I've got to become a genius in theoretical physics."
And elementary particles is the place where geniuses go at this point, we're talking about the end of the 50s.
"So maybe I should go to Princeton, which is reported to also have geniuses." But Princeton looks like a monastery. And by then, I was a shy, inhibited guy looking to maybe also go out on a date from time to time, and a monastery didn't seem that great. So for the second half of my senior year, this guy from MIT came down to give a set of lectures at Harvard. And that was Francis Low. And Francis Low looked super cool, you know? He was smart, lively, seemed interested, seemed... And I then checked out with my uncle, and I said, "Who are the up-and-coming young geniuses in elementary particle physics?" So he said, "Well, I'm an experimentalist." I'm sorry, I moved my computer again.
And he says, "The names I hear about are Chew and Low, and Lee and Yang." So Yang was at the Institute for Advanced Study, Lee was I think maybe at the Institute then too. Chew was in Berkeley. And hey, here was Low. So I said, "Okay, I'll go to MIT for graduate school, and I'll work for Francis Low." So that's how I went to MIT.
Now did Low accept you right away, or that was your plan when you got there to ask him to work with you?
He more or less accepted me right away. And then I did a very smart thing at the end of my first year at MIT. By the way, I decided to skip all my courses at MIT because I knew everything already. Except for one course on quantum field theory, which was taught by a Ken Johnson, a Schwinger protégé. So I didn't understand what Ken Johnson was saying either. So I went to Low in the spring of my first year at MIT, and I said, "Professor Low, I've taken every course, you know? I'm a genius really, but the truth is I don't understand anything." [both laugh]
You're too much of a genius. Why should you be bothered to understand things?
Incidentally, MIT made you take as an incoming graduate student an exam to check on whether you knew elementary physics, okay? I almost failed that, but I passed, and I said, you know, it's just because I've taken all that stuff so long ago I forgot. So I said to Low, "I think I really don't know anything." So what Low said is, "Okay kid, I think you need to look back at some sort of easier books and just rebuild." I remember he made me read a book by Max Barn called Introduction to Atomic Physics, and it was a terrific book with about 30 appendixes at the end. And I really liked that. It really was good for me. And then I really worked hard for six months rebuilding. And so at the beginning of my second year, I took the qualifying exams. And I passed them, and I did pretty well. So I felt on some quasi-solid ground then. And I basically stopped taking any courses and thought, "Okay, maybe I'll begin to work toward a thesis vaguely. I think I need to do a little more rebuilding before I go on to a PhD thesis." And I walked into Low's office then one day, and on his blackboard he had written "Rome?" So I said, "Professor Low, what does that mean?" And he says, "I'm thinking of going to Rome for a year." And at that point, on the promise of being a genius, I had gotten as a senior at Harvard a National Science Foundation graduate fellowship, which paid me a salary for graduate school. So I didn't even have to become a graduate assistant at MIT. Or a grader or anything. Which was lucky, because I really didn't know anything. [laughs] But I had this fellowship, so I told Low, "Hey, I'll come to Rome with you." And he said, "Sure." So he went to Rome for the year and I went with him.
What was he working on in those days? What was he going to do in Rome?
As far as I could tell, he didn't do very much in Rome. And I think Francis Low, who was by then in his mid-40s, decided, "You know, I think I've worked hard enough for a while. I'm going to have a good time in Rome." So I went to Rome and basically never saw him.
How could you have been productive yourself, if you had not settled on a topic and he wasn't really doing much of anything?
Well, he gave me a topic, which was going to be neutron-deuteron scattering. And I was supposedly going to work on this. It was supposed to be applying the Chew-Low Model to sort of low-energy nuclear physics.
Where was your lab? What was the institution affiliation?
No lab, he was at the university in Rome.
And I got tossed in with a bunch of, about four or five sort of advanced students in Rome. And I got along with them very well, and I sort of felt like an Italian then. And my parents were by then full time in Italy, because the passport office had eased up. So they had moved back full time to Florence. So I lived in Rome, and had a great time that year.
I was friends with some Americans at the American Academy. I had just acquired a girlfriend in Cambridge. She had graduated from Radcliffe, decided to come for Rome for a while. And Rome was terrific fun. But I didn't get to do much work. I applied for a National Science Foundation post-doctoral fellowship. I applied in March of my third year for this fellowship to begin a year from then.
What did you tell them you were ready to do? You didn't have much to show so far.
No. But I had heard about Yang–Mills fields. So I wrote this application, I was going to renormalize Yang–Mills fields. I had read about renormalization theory, and I had heard about Yang–Mills fields. This sounded interesting, so I told the Foundation I was going to work on the renormalization of Yang–Mills fields. [laughs] This is 1962, okay?
So I got this National Science Foundation post-doctoral fellowship. And in June, I went back to Cambridge, and I thought, "I better get a thesis out by March."
Because if I haven't, then I have to say, "Sorry, I haven't managed to do it." And then I've got to admit, "Gino, you're a failure." And so I worked really hard for the next seven or eight months and patched together a thesis. Now I had an NSF post-doctoral fellowship to go to CERN for two years. In the meantime, I'd also gotten married to this young woman I had met. There were two American post docs who had been there one year, and they were there for a second year, but neither of them had done anything. And so this looked scary again. But I managed to once again do some reasonable work, as a first-year postdoc. So I managed to write a few papers, and I guess if I'll say one thing about myself, as a technical physicist, I've never been that good. My grounding never was very good. But I've been ambitious, and I've always had a good feeling or a good sense of the direction physics is moving in. So for instance, not going to work for Schwinger and working for Low was a good move. Saying you need to back up and get some better grounding, good move. And so at the end of my first year, there was a craze then known in physics as SU6. Combining internal symmetry with spin. And I thought, this doesn't sound quite right. And there's this guy, Italian guy, Sergio Fubini, who's ten years older than me, and he's moving in this really cool direction, which is current algebra. And I talked to Sergio, and Sergio had a little group there of maybe three or four people. And he said, "Gino, I really like you because you know some field theory, you know some group theory." Sergio was great. Sergio was a genius on the move. So I worked with Sergio and we and a couple of other people there wrote some really good papers. And then, some other Americans there started offering me assistant professorships.
Professors who are also on sabbatical at CERN?
Yeah, they were older guys. So I was offered an assistant professorship at Duke, and at Maryland. But I didn't want to go to Duke and Maryland, so I said okay, let's go to a second post doc. And I said, I'd like to see the west coast. So I applied to Berkeley and Stanford. And got accepted by both. And I went to Berkeley. And at the same time, Sergio decided, "I want to go to America for a while." And he accepted a visiting professorship at Stanford. So we continued working together.
Now, why did you choose Berkeley?
Well, Berkeley accepted me first. And I thought, well, I like Berkeley, and the other half of Chew and Low is there. And then I thought, okay, maybe I'll also get to know my uncle, which would be nice.
Yeah. He was still there?
He was still there. So I went to Berkeley, but Stanford was, you know, less than an hour away. So I kept working with Sergio. And at that point, SU6 kind of died. And current algebra became very hot. So I became relatively attractive, and there were two very good assistant professors then at Berkeley. Korkut Bardacki and Marty Halpern. And they both wanted to work with me. Eventually, both of them got tenure at Berkeley. Chew was working on Regge poles, if that's a name familiar to you. You know, bootstrap theory Regge poles.
I didn't want to work on that. But field theory and current algebra was good, and I was working with Sergio, and that was great, and then Bardacki and Halpern wanted to work with me. And there were two young guys are Berkeley then who had just become full professors. They were in their early 30s. Their names were Steven Weinberg and Sheldon Glashow.
Now, what was, Gino at this point, what was exciting about field theory? What were some of the hopes that would come out of, you know, what field theory could do?
Well, what looked really good then was SU3. Current algebra and field theory was all looking good.
But you had mentioned earlier at CERN, that you said that you found some problems with SU3?
Not with SU3, with SU6.
Oh SU6, okay.
I said trying to combine SU3 with spin was a dead end.
Steven Weinberg left and went to MIT after my first year at Berkeley. And Sheldon Glashow went to Harvard. And Sergio went back to Italy and CERN. So I was looking for an assistant professorship then. There were a lot of assistant professorships then. This was the still the era when there were plenty of jobs--
But by then, I was also married, had one child born in Geneva, and a second child born in Berkeley. So here I was at age, let's say, 26, 27, with a wife and two kids. Berkeley wouldn't hire me because they had just hired these two assistant professorships. Stanford did offer me an assistant professorship, but they had the reputation of keeping assistant professors and then bouncing them.
Yeah, yeah. And who tipped you off to that? How'd you know about that?
Well, I was working with Sergio, and there was a third person in our collaboration. It was Dirk Walecka, a tenured professor at Stanford. He said to me however, "Gino, I'm going to try and get you an assistant professorship, but I worry, because I really like you, and we have this tradition of bouncing people. So I'm not sure I recommend it." Santa Cruz was attractive.
But Santa Cruz was, you know, a hut in the middle of the woods.
Seattle was attractive, but I had old parents in Italy, and my wife's family lived in New Haven.
East coast. So I'd better go to the east coast. MIT had just hired four assistant professors, and Francis said, "Hey, Gino, I love you, but MIT isn't going to work because we just hired four."
Just as well, probably. They would eventually bounce all four of them, you know. Because in the meantime they had managed to hire Weinberg and Fubini.
They figured, who needs assistant professorships? And Penn looked okay, you know? So I went to Penn.
What year? What year did you start at Penn?
And at first, I didn't really like Penn. You know? Berkeley, '65-67 politically was interesting. The free speech movement.
It had not gotten ugly yet though?
Not ugly yet, but I was all, you know. I've got to live in the inner city with the people.
Then I discovered that arriving there with two little kids and a third one on the way, I wasn't so keen on living in the inner city.
You know, there'd been lots of people at CERN. There was Sergio, Bruno Zumino, and many others. And Berkeley, Stanford, was a hotbed. But I got to Penn and there was very little in the way of new exciting particle physics. The Penn people started saying, "Okay, we want to rebuild.” So I wasn't happy. And then in my second year at Penn, Cornell offered me a tenure position. So I went up to Cornell, and it was really nice.
But you know, it was now 1969, and let me remind you that in the 60s, I had lived for three years in Cambridge, one year in Rome, two years in Geneva, two years in Berkeley, one year in Philadelphia. I had gotten married, had three children, and had flown to Italy a number of times to help take care of my parents, who were very old by now and my father was basically dying. And I thought, "I can't move again." You know? So I stayed in Philadelphia, and decided, okay, dig in here. You've had to dig in before in your life, so dig in here. So I did. I stayed at Penn, and decided, okay, let's try and build up things at Penn in elementary particle physics.
And in that-- And in, you know, on that level, and they're hiring you and being in building mode, right? What were their larger goals? What was the physics department trying to accomplish?
The physics department didn't know really what they were trying to accomplish. But--
Were they thinking about trying to enter into the upper echelons of physics departments?
Yes. And they were already in the upper echelons in many body physics.
Or condensed matter physics.
Because they had a couple of people. Eli Burstein, Herb Callen, older guys, experimentalists. No, sorry. Eli was an older experimentalist, Herb was an older theorist. These are two guys who would both eventually end up in the National Academy. And they had hired a really bright, young theorist, Bob Schrieffer. Who would eventually win his own Nobel prize.
They had two terrific, young experimentalists, Alan Heeger and Don Langenberg. Alan Heeger would eventually win his Nobel prize, and Don Langenberg was really good. They had a really good condensed matter physics group. They had a pretty good nuclear physics group. And nuclear physics wasn't yet dead. [laughs] And they wanted to build up particle physics. And particle physics was still in that mode of transitioning from nuclear physics to particle physics. They were trying to go to Brookhaven and to be big deals. But they weren't yet. And the same in theoretical particle physics. They weren't yet, but they had hopes. And they decided they had had one really young guy at Penn just before I came, Ben Lee, but Ben Lee had left to go to Stony Brook. So they were saying, okay, maybe Gino can help us.
And who was the institutional face of the department? who would have been the person to sort of communicate these structural goals to you?
It would be the condensed matter people.
So Bob Schrieffer took me aside and said, " You know, we're going to build. We're strong in condensed matter, and whatever you need, Gino, we're going to back you." And in the meantime, by the end of the 60s, one of the senior experimentalists at Penn, Al Mann, he took the bull by the horns and went into particle physics big time. He did this by joining in a collaboration with David Cline and Carlo Rubbia. So they became the famous Harvard-Penn-Wisconsin group at Fermilab. So they were a big neutrino group at Fermilab. And that was big time. And they were the competitors to CERN for all the big, you know, neutrino experiments that started in the 70s. And Harvard-Penn-Wisconsin also built a big low energy neutrino group at Brookhaven, and Brig Williams was the Penn guy at Brookhaven. And Brig was a real electronics hotshot.
So, experiment was on the way. And it was up to me to try and build theory. You know. So I had started in the late 60s. I thought a really interesting way to go would be weak interactions. To try and build a renormalizable model of weak interactions. So I did some fairly clever things in the late 60s, but Steve Weinberg and Shelly Glashow were all much better theoretical physicists than me, you know?
Did you work with them? Were you collaborating at all?
No. No. In parallel things.
But they beat me out at every step. Okay. So comes the early 70s, and things sort of break loose. I got a Sloan fellowship. So I went back to MIT for a year. I had had some ideas, but Shelly Glashow had beat me to it. I had some other things I was following, but I was barking up the wrong tree.
What were you after? I mean, what are the big questions that you're after, what are you looking to accomplish with this, you know, field of inquiry?
A renormalizable model of weak interactions.
Okay? That's what I was looking for. But I didn't get there. And then Yang-Mills field broke loose, you know? And I knew those people. David Gross was a friend of mine. He had been a graduate student at Berkeley. I knew David well. And David is smarter than me, more aggressive and he works harder. So-
Where was he? Where was Gross at that point?
He wasn't at Santa Barbara yet, was he?
No, no, no, no, no. David, after being, a graduate student of Chew’s said, “Field theory's the way to go." And he went to be a junior fellow at Harvard.
This is like 1969, 1970. He was offered an assistant professorship at Berkeley and at Princeton. Now, his wife was a really smart woman, and was also offered an assistant professorship at Berkeley in statistics. But he basically said, "Honey, we're going to Princeton. Because Princeton is where the action is now." So they went to Princeton. And the rest is history, David has done very well for himself.
He's also had a couple of very good graduate students, like Frank Wilczek and Ed Witten.
Yeah, yeah. Not bad.
So there I was and I didn't want to work in weak interactions, because I had had my cap set on being a genius and having the renormalizable model of... And there were a couple of years of sort of sour grapes on my part. But then I said, okay, Gino. Pick yourself up. I was also trying to hire some people, but it turned out not to be so easy. You know, the very best people were being snatched up. By that point, SLAC was becoming enormously attractive, so people wanted to go to Stanford or Seattle or Santa Barbara, or you know. So I was having some trouble, but we led the pack to hire Tony Zee. A really good guy, but Tony spent a couple of years at Penn. He had been an assistant professor at Princeton. But didn't get tenure there, because Princeton had Gross and Callan there. And they decided, we don't need Wilczek or Zee. So they let Wilczek go, and they let Zee go. Wilczek went to Santa Barbara, and Zee came to Penn. But then Zee also got snatched up by Santa Barbara, you know. By the mid ‘70s I was over my sour grapes, and said, okay. Let's go into, full time into weak interactions and also there's this exciting field now of unifying the weak interactions and the strong interactions. This is the way physics is going to move. I think it's an example of my maybe not being technically the best, of at least having the sense that this is a good direction.
And why would that be an example of you not having the best technical skills in this regard?
Because that's a direction also Glashow and Georgi were moving in. And they were better at group theory than I was. Okay? But it was also the time that I heard rumors that there was this guy named Alan Guth who had this really cool idea.
So I heard a talk by Alan Guth, who at that point was a post doc. You know the story of Alan Guth? I mean, he was a student of Francis Low's. Then got to be a post--
But you're a different generation? You did not interact with him?
A different generation. I didn't then.
But there's a sort of fraternal bond.
And he got to be a post doc at Princeton. But they thought he was okay, but not that great. So then he got to be a post doc at Columbia. So they thought he was okay, but not all that great. So then, he got to be a post doc at Cornell. So he stuck with it, you know? This was by now the mid-70s, when high energy physicists were not finding jobs, but they were moving them to Wall Street.
But Alan stuck with it. And so in his third post doc, he found this thing about the early universe and I heard about it. And I went to Bob Schrieffer and company and said, "This is our guy. We need Alan Guth." So off the bat, we offered him an assistant professorship. Then Minnesota offered him an associate professorship.
Did you match that?
Then we offered him an associate professorship. I went to Penn and I said, "This guy is gold."
Yeah, yeah. What was so exciting about the early universe stuff to you?
Oh, it looked like, hey, this is particle physicists, you know, moving into a completely new era. And he solved maybe some of the really big, big problems in cosmology. But particle physicists are going to move into cosmology with whatever tools we have. And we're going to revolutionize the field. This is something that really looks great. And let's get in on the ground floor while we can. And then, MIT offered him an associate professorship. [both laugh]
He's thinking now, I'm glad I stuck it out with the post docs.
And we couldn't beat that. But then I saw there's a junior fellow named Paul Steinhardt. And he's working on the early universe too. And people haven't heard of him yet. So maybe we can get Paul Steinhardt. And his wife is also a junior fellow in Chinese art, and they've got a very strong department. So we can get her an assistant professorship then.
And we can lock this up. So that's what happened, and Paul Steinhardt then came to Penn. And we had a guy named Paul Langacker who had been a post doc working with me and then we made him an assistant professorship. And then grand unified theories became hot. That was the area unifying weak interactions and strong interactions.
So that means, the effort to unify weak and strong interactions is directly related to the grand unified theory?
It is. Exact-- Well, they emerged independently. A renormalizable strong interaction, and then a renormalizable weak interactions.
Where does string theory play in on this?
String theory was in the woods, you know?
It was still in the woods?
Yes. But now people started talking about grand unified theories. If you've got SU2 for weak interactions and SU3 for strong interactions, as symmetry, what about combining them into SU5?
Mmhmm. Now, were you still a big fan of SU3? Was that still gold as far as you were concerned?
And was SU6, you were still unimpressed with SU6?
Yeah, yeah. Never to be revived.
Never to be revived. But SU5 looked really good. And SU5 and cosmology, ooh, so exciting.
Yeah. Why? What was so exciting?
Well, because SU5, a grand unified theory, what scale do they unify? One is strong and one is weak, but when they unify in some enormous energy, when they become one, it will be at the scale of ten to the 15th GEV. Ten to the 15 times bigger than ordinary accelerators. Well, what happens there at those enormous scales? We're talking about the Big Bang. You know? So the idea is, grand unified theories. Gravity, the Big Bang, it's all going to be one. And we're all going to live happily ever after, okay? So, I pushed Paul Langacker toward grand unified theories and moved there myself sort of, and Paul turned out to be a whiz. So he wrote big review articles examining all grand unified theories. And Paul is very good at combining millions of pieces of data and keeping them in his head and saying which looks good and which doesn't look good.
I spoke to him last week, and I got that strong sense.
An enormously hard worker and enormously reliable. So all of a sudden now, we had Paul Langacker and Paul Steinhardt on the faculty. And we were players.
Now how, what's the feedback mechanism for knowing that you're players? The kind of graduate students that you're attracting, the funding? I mean, how do you quantify the fact that there are these people and what that means in terms of where the department is going?
Well, graduate students, but you also sense it that these are the people who are getting invited to the big conferences. They're the rapporteurs at the conferences. They're the people who when you invite somebody to give a seminar, people are saying, "Oh, I'd like to come to Penn and give a talk." You know?
So... I mean, for instance, I had a friend. Do you know who Mike Turner is?
Okay. He's a leading cosmologist, okay?
Where is he?
He's now, he's just turned emeritus. He was at the University of Chicago. Mike worked together with a guy named David Schramm. They were the the two leading cosmologists, who linked to particle physics. So David Schramm then died in an airplane accident. But Mike Turner was the lead guy in Chicago. He's a great guy. He's now just retired, and he's gone to be the head advisor to the Kavli Institute. Okay. Mike and I had worked together on a paper. We had met in Aspen. So Mike came to Penn and I said, "Mike, we've got this guy, Paul Steinhardt, who's working on cosmology on Guth's type of stuff." And Mike latched onto him. And then Steinhardt and Turner wound up being a leading team in the link of particle physics to cosmology. It also helped that Steinhardt wound up discovering something very important in condensed matter physics. Quasi crystals.
So the condensed matter people, loved him. Eventually, sadly, all good things only last for a certain amount of time. Paul Steinhardt left to become the Albert Einstein professor at Princeton. And Paul Langacker sort of left. And particle physics now at Penn has moved in more mathematical directions. [laughs]
But there was a heyday.
There was a heyday in the 70s and 80s.
Yeah, yeah. But to what extent is that unique to Penn?
Sorry, I had to turn... I'm sorry, what?
My question is, to what extent is this heyday unique to Penn? I mean, for example, I talked to Leonard Susskind, and he says particle physics has really been, you know, nowhere in particular for the past 20+ years, 30 years.
Yeah, I think that's pretty accurate.
I'm sorry, I have to...
Go ahead, do what you need to do.
No, no, no. It's just, I've got to turn off my iPhone.
So let me do that. Okay. So what happened was particle physics reached its heyday at the end of the 70s and the early 1980s. Okay, can you hear me now?
Okay. I mean, that's when, you know, the intermediate vector boson was found, the Z boson. By the way, as a historical note, when I was at CERN as a post doc in 1964, CERN announced it had found the intermediate vector boson. [both laugh] It made first, front page of the international Harold Tribune. It turned out to be in experimental error. It was a big embarrassment, you know.
Yeah, oops. [laughs]
But that's another matter. So particle physics, you know, that was the heyday then of particle physics. And string theory grew out of that in the 80s.
And the idea was, okay, we've unified the strong interactions and the weak interactions. We're all up there at the cosmology scale. Let's go the next step and unify this with gravity.
String theory grew out of that in the 80s. Green and Schwartz wrote a famous paper, and then Ed Witten emerged on the scene, you know, and he really is a genius, you know? But not too much has happened really in particle physics since 1980, okay? CERN keeps marching on, the SSC got canceled, the LHC is a big deal. They've announced the discovery of the Higgs boson. Which many of us, like Lenny Suskind would probably say, "We all knew it was going to be there, but it's still very nice to see it, you know." And CERN they're upgrading the LHC ad talking about what they hope to discover in the future and so on.
Now, when the SSC got canceled, so let's pretend that it didn't get canceled, right? How confident would you be that the assertion that particle physics hasn't really gone anywhere for the past 30 years would hold true still? In other words, would SSC really have changed the game for particle physics?
Because the so-called "fundamental model" of elementary particle physics, was basically set by 1985 or so. That is, you had a renormalizable theory of weak interactions. You had a renormalizable theory of strong interactions. You had a conjectured grand unified theory. And unless you could go a step beyond that experimentally, then you were just having conjectures of what might be a deeper truth.
Yeah, but even if you want to say, like, you see the-- So fine, you see the Higgs boson. But we knew it was going to be there, right?
We strongly thought it was going to be there.
But you still need the experiment to demonstrate it, though, right?
Absolutely. Absolutely. But you know, for theorists who dream of bigger game, there hasn't been anything which has changed that model, okay? Something might yet show up in neutrino physics. Which would change the model.
And neutrino physics has been interesting. But in high energy physics, there hasn't been an experiment that says there's something wrong with the theory of weak interactions. There's something wrong with the theory of strong interactions with which we have. There's something wrong with the unified theory. There aren't any particles beyond that. We've discovered six quarks. We've discovered the intermediate vector bosons. We've discovered, or believe, have good evidence that there are quarks, there are gluons. We keep talking that maybe we'll discover supersymmetry. But there's no experimental evidence for it.
Is there a facility that could be built that could demonstrate the evidence?
The hope was that the LHC would do that.
It has not. And so now the hope is that the upgrade of the LHC will discover it.
I mean, that gets to a bigger question about, you know, when do you, how do you determine that if a given facility does not prove a particular theory experimentally, at what point do you say, well maybe there's a problem with the theory? Maybe that this is just not something that can be done, because the underlying theory itself is faulty?
I think you don't say that, because the underlying theory has worked so well.
But this is a new area, though. Right? Isn't it extrapolation?
Well, grand unified theories is an extrapolation. But weak interaction theory is not an extrapolation, and strong interaction theory is not an extrapolation, there's good experimental evidence for them.
Is it an extrapolation to unify them, though?
To unify them is an extrapolation. But there is suggestions, strong suggestions that they're true. And the strong suggestions make it enough to keep on going. I'm not saying you should stop going, you know?
But it's enough to keep it going, but the argument I say is if a bright 20 year old comes to me and says, "I'm really good at science, you know, and I really like this stuff. Is elementary particle physics the field I should go into?"
You're going to say no unless this kid's a genius, is what it sounds like.
I would say no. I mean, now we're talking about experimental, okay, physics. Would I say yes? I'd say no.
So we've been talking, Gino, you know, we've been... The perspective of our conversation has really been sort of at 35,000 feet in terms of your assessment of the field and your colleagues. We haven't really talked in the, you know, from the 70s and 80s and 90s, what specifically you were working on during these years, and how you played a role either in demonstrating that the field hasn't gone anywhere, how you might have responded to that in terms of the projects that you decided to focus on.
Sure, but let me go back for just one second, okay?
To what we mean by a "genius." Okay? There's a guy at MIT named Feng Zhang, Z-H-A-N-G. Okay? He went to Harvard, came over from China when he was 11. Went to Harvard as an undergraduate. Then went to Stanford for graduate school. There he worked on a really revolutionary theory called optogenetics, where you can make certain genes be optically visible. And you can see them with lasers, you know. You can study the brain et cetera. Really important stuff. It was, I think, Nature's breakthrough of the year in 2011. Then he became a junior fellow at Harvard, and then got a joint appointment at the Broad Institute and MIT. He has now an endowed professorship at MIT and is a senior fellow at the Broad. He's a member of the National Academy of Sciences. He worked on CRISPR. He's likely to get maybe a Nobel prize with Doudna and Charpentier. He's also now developed a new technique to test vaccines for corona, okay?
I was hoping you were going to say that.
He's 38. Okay? [both laugh] If this guy had gone to particle physics, you know, he would be planning on the build-up for the LHC in 2029, you know?
That is to suggest, though, that you know, at a certain point, a field gets what? Saturated, that genius is really not really... Is no longer part of the equation in terms of pushing the field forward?
Well, I mean, let's take it, if you were a genius in 1932, you went into nuclear physics, okay?
Right, right. But that's when you're talking about working in a found-- during a foundational era.
Well, the era from 1954 to 1984 was the foundational era for elementary particle physics.
Okay? And the classic breakthroughs are the discovery of non-conservation of parity. The discovery of SU3. The renormalization of the weak interactions. The establishing of the fundamental theory. So it is the foundational era. It doesn't mean that the field ends. There's still lots of good stuff to do. But the foundational era is probably over, unless there are some major breakthroughs. Now there always can be, because elementary particles is the field that says, we're looking at smaller and smaller bits of matter. So maybe someday, you're going to find more elementary particles that will change it. But if you haven't found things for 20, 30, 40, 50 years, people start to lose interest.
So back to me.
Right, right. And did you figure this out sort of in real time? Like when you say, you know, '54 to '84 you saw, this is not just you reflecting back. You saw this playing out in real time?
Well, I did. And then I comes string theory in the 1980s, okay? Maybe this is the next big one. You know? Maybe string theory is where we're going to unify the grand unified theories with gravity. And in a beautiful, a model of such beautiful mathematics that it will astonish everybody.
And when string theory got out of the woods, so to speak, what was the relationship between that and unifying weak and strong interactions?
Well, the idea was that now that SU5, okay, the unified theory of weak and strong interactions was going to become part of a yet bigger group. SU8. SU32, the exceptional groups. It was going to be part of a bigger group, and we were then going to be able to explain it all. So I went into super string theory as much as I could. I wrote some papers on the phenomenology of super string theory, uniting them with grand unified theories. I gave a well-received set of lectures at a summer school in Corsica in 1985. I think I got more demands, you know, in terms of requests for the copy of them for those lectures than anything else I had written in my life. I think I got some, a couple of hundred cards for copies of those lectures. But then I began to feel two things. Is this really it? You know? And the second thing is, this involves mathematics that I can't keep up with. I can't do this again. I'm back to not understanding what people are talking about.
[laughs] Right back to freshman year at Harvard.
Freshman year at Harvard. And by now, I'm in my late 50s. Time to do something else, you know?
And that's when I moved into writing books.
Bob Jaffe made a very similar point about particle physicists have to be careful about how they age in the field. A remarkably similar point. And I said, "Well, aren't you wiser as you get older?"
And he said, "Yeah, but wisdom and particle physics, they don't go together as well as you might think."
In fact, it's probably a drawback. Because when you're young, you say, "Oh, I have this great idea. I have this great idea, it's going to make me famous and I'll become one of the greats." You know? "Let me work night and day on it and then I'll be famous and get invited to be a rapporteur at the big conferences." When you have an idea like that when you're older, you think, [laughs] "Been there done it, and I was wrong then"
Yeah. So Gino, my question is, when you start to become the, you know, known for your literary achievements while you're still a professor, was that a tough sell in terms of easing off the research? Was the department not thrilled about this development, or was this sort of good for them in unique ways?
By then, I was enough of a has-been, I felt. The last good paper I wrote was, I had an idea, there are stars called pulsars, and I went to a talk and I heard somebody say there's this problem with pulsars. At birth, they get a big kick. They move all of a sudden at birth, they shoot off at about a-- up to a thousand kilometers a second in one direction. So I thought, hmm. Now I happened to know that pulsars, when they're born as neutron stars, 99% of their energy comes out as neutrinos. So I said, maybe the kick is because neutrinos go preferentially in one direction instead of the other. So if neutrinos go in one direction, the pulsar will recoil in the other direction. And so I know about neutrinos. So now I've got to figure out a model of neutrinos that will mean that in the inside of a collapsing neutron star, they go preferentially in one direction rather than in the other. So I went into that field with a post doc of mine. A guy named Alex Kusenko. And we wrote some good papers on it. But I was too old. You know? And he went off into astrophysics, and he's now a professor at UCLA. Probably in his early 40s. And he is what I would have like to have been if I had been 30 years younger. Namely, what I would have said is, string theory is too hard for me. The math is too hard. But maybe I can go into astrophysics and neutrino physics, because I know something about it. And maybe I can retool. So that would have been the fourth or fifth, you know, retooling in my career. So when I--
Did you ever talk to Gene Beier about these things?
I do, but Gene is a hardcore experimentalist in neutrino physics.
I mean, in particle physics as a career, it's important to retool every decade or so. And the success stories are the people who've retooled. Okay?
They've done their own decadal service, surveys it sounds like.
That's right. So David Gross starts out as a bootstrap Regge pole guy. Then he retools as a field theorist. Then he retools as a string theorist. You know? Then he retools as the head of the Santa Barbara Institute, you know? I mean, there are some people who keep on doing the same thing. God bless them all their life, you know. But those are people who are really, really good at a certain technique, and they've got a hammer, and with that hammer everything looks like a nail, you know?
So they keep hammering on it. But there are also the people who retool. And I'm basically a retooler. And haven't hit the big time, because I'm not good enough at it. You know? But I have the right instincts for a retooler. And I've had the good taste to move in the right directions. It's just I haven't had the ability to be, you know, at the very top. To join the Weinberg [laughs], Glashows, Wilczeks, et cetera. They're really good at this.
What's the difference? It's the math? Is that what it's all about?
It's a combination of things. It's a combination of math, brain power...
Imagination? Is imagination part of it?
Imagination. Excellent working habits. You know? There's nobody like Weinberg. He can calculate anything, I mean he can do anything. He's constantly reinvented himself, but as a leader in whatever field he goes into, including book writing. And then there are people also like Shelly Glashow. He has better sense than I do of experiments, what experiments are the most interesting. He's able to stay very close to those. So I mean there are different ways in which you can be the leader. And at best, it requires all of them. I mean I wrote a book about Fermi, a biography of Fermi.
Right. Did that grow out of your chapter on Fermi? In 2012?
No, no. I mean, if you want my book writing history, the first book is A Matter of Degrees.
So then I said, okay, I'm a book writer. I'll write a second book. The second book is called Faust in Copenhagen. And the subtitle is "A struggle for the soul of physics." And it grew out of a meeting in 1932 Copenhagen, where the geniuses all assembled, and it ended with the young ones, the 25 year olds, putting on a skit, making fun of their elders, the 30 year olds. And the skit was an adaptation of physics to the world of Goethe, of Faust. Which everybody knew. I had a copy of the skit, so it was an adaptation, it was a bit of history. By that point, I was moving away from physics, okay? So it was a little bit of history, a little bit of Goethe, a little bit about the skit, a bit of the individuals. And that got me to my third book, which was a biography, really. Two people in that group in 1932, namely Delbruck and Gamow, they had said, "Yes, we've been trained as nuclear physicists, but there are too many people in the fields. Let's move into a different field." So Delbruck said, "Okay, I'm going to move into the theory of viruses." And Delbruck wound up being the founding father of molecular biology. And Gamow said, "Okay, nuclear physics, I think I can apply this to cosmology." And he wound up being the theorist of the Big Bang. I liked the two of them as characters and they were friends and they were roommates in Copenhagen, and they were also both real characters. So that was my third book. But by then, publishers have figured out, this guy's never going to write a best seller book. [both laugh] He was sold to us as the next Brian Greene, you know? But this guy is nice, you know, my editor at Viking really liked me, I liked her. And she says, "Gino, we love you, but you're no Brian Greene." So then my fourth book, I figured I had to write something I could sell. And so I started to write a biography of Fermi. Not so interesting as a character, but really a great physicist. And then I knew the Italian history, the émigré history, and all that.
What did Dick Garwin say to me? He said, "Fermi, you would mistake him for the corner butcher if you didn't know better."
Exactly. You'd take him to a museum, and he starts taking out a slide rule to figure the relative height of-- You know. [both laugh] But he was a great physicist.
And I could write about physics, Italy, the émigré experience. And my wife co-wrote the book with me then. And she grew up at Los Alamos. So she's not a physicist, but her parents also came to the United States in 1939 and her father was a physicist, so it was a familiar world.
So we had fun together, writing it.
Yeah. So what's next? What's your next book?
Ah. Well, actually, a new book is going to come out pretty soon. While working in the Chicago Fermi archives, I discovered some scribblings which said, "Fermi geophysics 1941." So I looked at those scribblings, and I said, boy, this is interesting. Of course he's a genius, since he knew everything, he probably already knew geophysics. So I went back after the Fermi book and looked at those notes, and found that he taught a course on geophysics. And these were his little notes for them. And I decided to make this into kind of a monograph, a little book on geophysics, which would be the notes that an ambitious and reasonably smart student would have taken on this course. So that meant I had to learn geophysics and reinvent myself. So I went to the University of Chicago, and I said, "Are you interested in publishing this?" And they said, "Sure." And then I was lucky to find an old Berkeley post doc, a friend of mine named John Stack, now a professor at the University of Illinois at Urbana, who was interested in Fermi. So we did it together. And it's coming out, and then I consulted my wife on a title, and it's going to be called Unearthing Fermi's Geophysics.
[laughs] Is this going to be the best-seller that the biography was not?
Strictly for physics juniors or seniors.
Who are saying, "What field can I move into? And that maybe still hasn't been recognized as such?"
But you're talking now in your capacity as a science writer, not a physicist?
This is all equations.
But it is true. You know, all those physicists have certainly moved into astrophysics. But they haven't really discovered geophysics. And there may be some gold to be found there. Who knows? There are interesting problems. Why does the Earth's magnetic field flip every few hundred thousand years? There's something that goes on in there. And maybe they will come up with some good ideas for global warming along the way, you know?
Well, Gino, I think for my last question, I mean we've spent so much time hovering around the topic, but I want to ask you sort of more directly, you know, forward-thinking. Again, more in your capacity as a physicist. I love this concept of "retooling," right? And that, how universal it can be applied no matter what your particular area of interest is at any given time. So, you know, for that, let's go back to that 20 year old, right? Really bright, things like that.
And let me just add one question, okay?
Wall Street recognized this, okay? In the 70s, there's few post docs and so on who stuck it out and got jobs, but the large number went on to Wall Street. Why? Because Wall Street said, "These are smart guys and they have certain tools. Let's just hire them and then we can train them." So this is part of the retooling. So Wall Street recognized it, figured they could make money out of it, and isn't it important for scientists, really, to retool? Not for everybody, because there's a lot to be said for just having expertise that gets transmitted. But there should be a group that retool.
Although a physicist that gives up and goes to Wall Street, that's a loss for science.
That's a loss for science. I'm just saying that Wall Street recognized that these are people who are good at retooling.
Yeah. Yeah. So my question is, you know, staying within physics, right? Retooling within physics. So that 20 year old who comes to you today in 2020, right? This idea that, you know, every decade that they should retool. What do you see, and again obviously, there's a lot of conjecture, who knows what's going to happen? But what are the kinds fo broad pieces of advice that you would give this student in terms of, you know, in the next ten years, this would be an interesting thing to focus on? And based on that, then I would suggest this would be an interesting thing, and so on and so forth. So where do you see-- I guess that's a general question that I had that I'm tailoring to your particular way of seeing how these things work.
Well, I think for instance, biophysics is really interesting. And you're seeing a lot of physicists already starting to move into that.
Including Irwin Shapiro. 90 year old Irwin Shapiro at Harvard. We ended, he talked to me, he said, "Why is an onion and a human so similar at the molecular level? We don't really have a good answer to that and I've been looking, you know, up into astrophysics my whole and I think this is what I'm going to do now." And I wasn't thinking of the word then, but if there was a perfect exemplar of what it means to retool [laughs].
That would be it. So I'm sorry, go ahead.
No, but I mean, suppose you have a training. You're a laser jock, okay? You've written a PhD on, you know, studying the crystal structure of something or other by lasers, okay? Well, what about optogenetics? What about soft condensed matter physics? There's a better way to treat medical physics. People are starting to use nuclear physics to do cardiac ablations. You may not have to split somebody's chest open to do bypass surgery. There's no reason why you have to diagnose urinary problems by sticking catheters up people's organs, you know? So these are fields where physicists, you know, have some training and they need to look at those areas. So I think these areas, biophysics, astrophysics, geophysics? Those are ripe areas for retooling. That doesn't mean everybody has to leave particle physics, not at all. You want to keep some people who are really good at it. Keep them doing super string theory. But it doesn't mean that we need to have quite a herd mentality. So that's my wisdom of the ages, you know. [laughs]
Well, Gino, it's been great talking with you. I really appreciate it. It's been a lot of fun.
It's been a lot of fun.