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Interview of Bruno Coppi by David Zierler on April 28, 2020,
Niels Bohr Library & Archives, American Institute of Physics,
College Park, MD USA,
For multiple citations, "AIP" is the preferred abbreviation for the location.
Interview with Bruno Coppi, Professor of Physics Emeritus at MIT. Coppi recounts his childhood in Lombardi, Italy. He discusses his early interests in nuclear engineering and his graduate work in Milan on neutron transport theory. He explains the opportunities that led to his postgraduate appointment at the Princeton Plasma Physics Laboratory and his subsequent work at Stanford for his postdoctoral research in collision-less plasma. Coppi discusses his work at the Institute for Advanced Study where he interacted closely with Freeman Dyson, and he explains his decision to join the faculty at MIT where he could work with Bruno Rossi. He describes his collaborations in the Soviet Union with nuclear physicists, and he explains the sequencing of the Alcator program to the Ignitor program. Coppi describes the changes inherent in the AEC’s transformation into the DOE, and he explains the import of the Voyager 2 space mission. He describes his current interest in spontaneously rotating plasma and he reflects on why science is a humbling profession, even for geniuses. At the end of the interview, Coppi explains why the role of angular momentum remains profoundly mysterious, and why he is optimistic that he will continue to make contributions to the understanding of burning plasmas.
Okay. This is David Zierler, oral historian for the American Institute of Physics. It is April 28th, 2020. It's my great pleasure to be here virtually with Professor Bruno Coppi. Professor Coppi, thank you so much for being with me today.
Okay, so let's start right at the beginning. Tell me about your birthplace, and your early childhood in Italy.
Oh, well my birthplace was the last [inaudible] of the Lombardi region, which is now affected horribly by... And so I grew up there, and of course, I was greatly affected by the war. And you know, the type of situation that we, you know, with the coronavirus and all the uncertainties, [inaudible] there, and the...
Were your parents from Lombardi as well?
Yes, they were from that region.
And what was their profession?
Well, it was, my father had gone to the fourth grade and mother the fifth grade, and at that time, you know, fascism, it's kind of treacherous code. You switch away if you are from a humble family, you could not proceed. So there was, at the end of the elementary school year, you would need to go through an exam, but call admission to go to an intermediate school, and that was kind of discrimina-- It was a real discrimination. So my family never thought beyond this, [inaudible] that I would become a highly-specialized machine, tool machine operator.
So I went to a school in the evening in order to prepare for that type of... I would never have gone to university, but at the [inaudible], the teacher was very stubborn. So he insisted that I go to that exam, and it could take some children from nearby region, which is Emilia. And so I came out on top of that. So that determined the fact I could go to intermediate school. And then I went very well, I went to the... Then at the end, let's say, of the high school, which is an extra grade in Europe, it's called liceo. I was admitted to a very prestigious college. Colleges are different. They are like in England. They are part of a university, but if you get in one of these, there were... Okay, now we rejuvenated by Napoleon. They, my case, they took about 20 students or less per year. They would support you up to your PhD. So then I went to university for the year, and then to the Politecnico of Milano, where I was admitted to the first group of students selected, eight to enter nuclear engineering, because my father was very ill. In fact, he died of a heart attack. So I was afraid to go into... I was more cut to do mathematics or physics. So nuclear engineering was a--
Yeah, a compromise. But I had excellent teachers in mathematics, I would say so.
Now Bruno, your high school, was it a public school or a private school?
No, no. It was not. It was a public school. And in Europe, the private schools are minority basically.
Yeah. Did you have a religious education at all growing up?
Not at school. Outside. But those were days where we, you know, the Communist party was very strong. There was a, the Cold War there, in Northern Italy was quite felt.
Because, you know, fortunately, the Americans had the great idea of the Marshall Plan. Otherwise that region would have been completely Communist.
And so, but I was very lucky. This public school that I went to, this was in Mantova, Mantua. And was extremely good. It prepared me very well. But the next step was at the University of Pavia. And this college is called College of Ghislieri. And it was founded in the 16th century. So there I had the opportunity to interact students from all disciplines. Some of them, one of them he became professor at Harvard in medicine, we had been friends for our life. So that was a great step for me. The next step, I'll skip a little bit, was when I went to Princeton. Going to Princeton, that was the end of '61, was another experience, great experience, as I had going to Pivia, to the world intellectual community.
But wait, before we get to Princeton, we have to talk about your graduate work in Milano. What did you do your dissertation on? And was it in nuclear engineering? Or did you do to physics?
Oh that was [crosstalk] yes, yes. I did some small amount of experimental work, but mostly I was engaged in neutron transport theory. And I think, and then I also was a lecturer of kind of, not assistant professor, in that field. Now the disadvantage of that field, there was a great deal awarded, been done in the US, that was classified. And also by that time, the nuclear energy had become a [inaudible] field, so a great deal of the work that I did as a graduate student, in a way, had already been done. In fact, when I went to Princeton, Wigner told me that, you know, it was not the field that I should continue. In fact, I got to Princeton to work in plasma physics and space and so on. And--
So, what was your dissertation specifically on? What did you work on?
Oh, on neutron transport theory.
And what were your findings? What was your contribution with this work?
Well, by now, I did not prepare. The contribution was that... [inaudible] neutrons, I forgot about that now. [both laugh]
It's a long time ago.
A long time ago. But it was highly appreciated. In fact, I was offered a job to go to [Turin] to set up a laboratory in this province, but I prefer to stay at the University of Milano, where I could do more theoretical work, and also teach. I taught...
No. I taught immediately to graduate students. And again, neutron transport theory control and so on.
Now was Milano, was Politecnico at Milano, was it a leader in this field, or were you at the beginning of this work?
Well, there was a collaboration between the Politecnico of Milano and the university. And I was at the beginning of it. There was a professor, Professor Caldarello, who had been a theorist, and he'd introduced me to the subject. But in a way, we were the first one. In fact, was the first one to teach neutron transport theory and so on.
And how connected were you with other universities in Italy or in Europe? Did you go to physics conferences elsewhere?
Yes, yes, yes. I went to physics conferences, and so we were connected to the University of Rome, but they were not very much involved in that. And I went to European conferences. I was well-established in the field, if you want.
Yeah. What about on the other side of the iron curtain? Did you have any collaborations in Eastern Europe?
Not yet. There was a famous theorist in that field. I think it was Marchuk. He had written a book that was quite advanced, and I had some connection with him, but not much. My connection with the Russian became very intense, if you want, after I moved to Princeton.
Yeah, yeah. And so what was your connection with Princeton? How did that offer come about?
Okay, let me explain to you. I think it was in the fall of 1960, there was a big conference in Varenna. Varenna is a place of the Lake of Como, where the Italian Physical Society at that, so it was on space. And there were all the luminaries of space. And I was invited to go there because the luminaries in fluid dynamics like [Paul Carbone], [Crocco] was Italian, and so I got exposed to space, it was quite fascinating. And then they all insisted that I should go to the US. But, I was well-established in Milan, and so I had some doubts. So I had number of offers. So I accepted to go to Princeton. The professor who invited me was a famous Italian aerodynamicist, it was Crocco. And when I went there, that was great experience because I began to meet famous people that I have known and trained for all my life. For example, Wigner. I'd met him in front of the movie house in [inaudible] Street in Princeton, and I have read his books, a great admiration for him for all he had done. If, you know, there was a famous book by Weinbach and Wigner, even neutron transport theory. And he realized I was terrified. And he said, "Don't worry, Doctor Coppi. I am finally able to solve a 2x2 matrix." [both laugh]
That made you feel better?
Yes. And then of course he discouraged me to, he felt that I was right to abandon neutron transport theory, because of the reason that I mentioned. There was a great deal of [connection cuts out] classified and also industrial type, and so.
Now, was this your first time to the United States, when you came to Princeton? Or you'd been before?
No, that was my first time. But the other--
And how was your English?
Oh, it was fairly good.
Because I had it in high school, and so I had no problem with the English. The major problem I had when I interfaced with the Princeton plasma physics laboratory, you know, that was part of the Manhattan Project. That had been led by Wheeler, and then after the H bomb work was completed, he turned to fusion research. And at the beginning, at the laboratory, there are, it was not classified language. There was no-- It was free. But there on language quite [inaudible] and so. But they put me to work with an excellent person, Ira Bernstein, who was been a friend for my life. But he put me on a subject that was very difficult. Now it is [connection cuts out] connection that is the, it's very important in astrophysics and space and so on. But it's still a very difficult subject.
So I was quite... I had problems, because Ira did not have experience too. He probably, he was overconfident of both of us. But then at the Christmas party, the head of the theory group, that was Ed Freedman, he came to see me. He said, "Bruno, I had a failed paper." That he had written with [Rottenberg]. That he felt that perhaps I could do better than they had done. And that paper opened my eyes, because I tried to remedy what... I discovered there were new plasma modes that involved what is called now magnetic recognition. I found the first so-called resistive [inaudible] abilities. And that opened up a new field for me. And so now, so then I got invited to-- In those days, there were symposia called Locus Symposium near Stanford to speak about that, so I got involved more with the people working solar physics and space and so on. And this is where Stanford, this is where I went after Princeton.
But before moving to that, let me tell you about my great experiences at Princeton. And the professor [inaudible] were part of a group of intellectual that was partly European and partly American. You know, and there were people like [inaudible] was a member of that group. Morgenstern and I remember, let's see, [Casasui] was a pianist. Jaques Maritain was a famous philosopher, French. And I remember a Russian composer, Lourié, who had married a Romanov, from the Russian family. They spoke Russian with each other, only the servant, they spoke French, and I spoke French with them. My French was quite good. And Marston Morse was the famous mathematician. So that, together with plasma physics, was a great experience for me. Because Princeton at that time was probably the best place in the world, one of the best places in the world, to...
You mean just generally? The level of scholarship there across the board?
Right, right. It intimidated me. Goodell was there, but I never, I met him later. Because I was at Princeton twice [crosstalk]. And that was extraordinary. It's from a terrible atrocities like the Holocaust and Nazism. Something like that came out. It was quite incredible. And for me, that is probably being the greatest experience in my life. Having, being in touch with these people.
Yeah, yeah. Bruno, I want to ask you, in Princeton, how much of the work that you did was self-directed? In other words, did you decide the kinds of research projects that you would work on? Or were they handed to you by either a lab director or someone else?
Well, unfortunately not. It was self-directed. Because nobody had ever worked in that area. In fact, it represented a track to be... There was a big program called Alcator, [inaudible] confinement that see by [inaudible], who was a well-known astronomer, but you know, the machine that he had conceived was so complicated and with the type of collective mode that I had found, you know, it did not look, did not come out too well. But it did not restrain from working that field. Not only, but I began to go beyond Princeton in very much focus on ideal MHD magnetohydrodynamic equation. I rarely got that sum, but it's quite restricted. So go beyond that. And so it was completely self-directed. And in fact, I would not say it was unpopular, but I did not have any real... We had some collaborators toward the end of my stay at Princeton. There was a great man that people, John Green, underestimated. We began to work together on that.
And what kind of interaction did you have with the physics department at Princeton? Or even the Institute for Advanced Research? Study, I should say.
Yes. The, as you probably know, I went twice to Princeton.
That was the first. With the Institute, not too much. What happened was that my wife had followed me. At that time, I spoke to Wigner, and well, there were not even the bathroom for women at the university. And I didn't know that. So she was very good. Very good, so she was accepted at the Institute. So I had connection with people at the Institute because of my wife. And the physics department, Goldberger I had interaction with, and then Goldberger was a friend of Rosenbluth's and I ended up working with Rosenbluth later, and so on. So it was... But the physics department was quite separated in a way. The, at that time, you may be interested, Johnny Wheeler was going around Princeton rather distressed, saying that the physics was at an end. [inaudible] You know, I love him, you know. He liked to exaggerate. But I didn't know at that time that his secret, he was working with general relativity.
So that when I went to Princeton the other time, the other time, I was first at the university as assistant professor, but then at the Institute, because they decided to establish the school. At the beginning, they only had the school of mathematics. And Goldberger felt that this would invite physicists that would work with the laboratory with experiments. So Rosenbluth and I went there. So as soon as we went there, Wheeler began to visit us and he had to... The physics room was very small. We had a very small building, made of two floors. I think there were four offices for each floor. On the second floor. And there was Reggie from Italy, and Rosenbluth, myself, Dyson was there. We used to go to lunch every time. And Wheeler began to, when he learned that in fact I was an expert in plasma physics, he immediately latched on with me because he [connection breaks up] hydrogen bomb, he knew that plasma were important. And in fact, we were probably the first to think of plasmas around black holes. And that is, by the way, a subject which is still now not accepted by the community. People study black hole as if there is nothing. Vacuum outside. In reality, we began to speak about shining black holes a long time ago. So, but then [inaudible] now I am jumping.
You probably know that black holes and gravitational wave are very unpopular. Especially in the Cambridge area. When I came, Rainer Weiss was already here, at MIT, had come from Princeton. But nobody wanted to hear from Ray about the [inaudible] interest. He began very early to be interested in gravitational waves. And I was answering black hole, but nobody for many years, they could not, even now, you know. The word "black holes" is very popular. One of my graduate students at Princeton, Jeff Crew, is being one of the main people working on the famous picture of black holes that you have seen last year.
But still, black holes with plasma [inaudible] and high energy plasma physics, something which is viewed with some suspicion. You know, still, the time when I went to Princeton, general relativity was practiced by very few people. Wheeler and this group, they looked like conspirators. Mesner was with him. Kip Thorn, and so on. And now I am jumping. And I remember very well that one afternoon Saturday I was fixing my car. Those days the car were simple. I was at the Institute. So [inaudible] to see me, so he asked, I don't know, Ruffini that was one of his pupils, to call me up and go there, he had some question of plasma physics [laughs] and so. But we were very small minority.
Now, when Wheeler said that physics was at a dead-end, what did he mean by that?
That's a good question. You know, he had written this famous paper on fission with Bohr. And I think that... I had not talked to him, then I became quite friendly with Wheeler. We loved each other, really. And the, I think he was referring to nuclear physics, basically. And then I thought that he had discovered [connection breaks up] at that time, but Ray Weiss told me that the reality had begun earlier to get interested. You probably also know that when I was at Princeton, Oppenheimer, you know, had been taken very much by this dispute on the hydrogen bomb and so on. So he had shown no interest in black holes, even though he was, he wrote the original papers. And by the time I went to the Institute the second time, Oppenheimer was dying, unfortunately.
And he was walking too much.
Now, when you decided to leave Princeton, was it a fixed term? Did you know that your time was up, or could you have stayed on longer if you wanted?
That is a good question. I do not remember. I was quite fascinated by the Stanford place, because of the early [inaudible] of space was very important.
And so they offered me to go to work on solar physics, and so that is why. So I do not remember whether my term would have expired. But I think I wanted to go, to broaden my experience in plasma physics to space and astrophysics.
And so then how did you see, how did California work out for you? How did that come together?
Oh, very well. Let me speak about that. The Stanford was a very active place those days. I went to work with Professor (Peter) Sturrock . He wrote me last week, he had a question about solar neutrinos and so. And at that time, they were setting up the SLAC. And in fact, I used to be invited. (Pief) Panofsky was the, he used to have parties every, like, Saturday, he used to invite me. I used to go and met very interesting people, of course.
Bruno, I have to tell you, just yesterday I interviewed MaryBeth Beerbohm, who was Pief Panofsky's secretary for 50 years.
Oh, I'm delighted to hear.
I'm doing a bigger oral history project on all of the major people at SLAC, and so I learned all about Pief and from a personal perspective. Just yesterday, I had this interview. So I'm thrilled to hear you talking about Pief as well.
I see. Well, speaking about that, you know, I'm sure you must have talked to Jerry Friedman in my department.
Not yet. Is he still with us?
Oh yes, he's at home, and he's, we are very close friends. And--
Okay. So your first--
[crosstalk] unfortunately, he di-- he's not [inaudible].
Came from Princeton. But unfortunately, he died.
Yeah. Yeah. So your first contacts out west were at SLAC? They were not at San Diego?
No, no, it was at the university. It was not SLAC, I was invited by Professor Sturrock. He was in solar physics, and my office was close to Schiff. You know, Schiff was an excellent theorist. And the highlight of that year was actually the visit by [inaudible]. We became very good friend, and the friendship with him lasted until he died, basically. And I remember he was a very precise person, and he liked to work operational principle, where you put trial function, and he used to compute the [inaudible] value with the huge slide rulers. That was the year when quasar were discovered, and so we had an exciting time. So I was at the university.
Yeah. And at that time, was it only graduate students, or were there undergraduates there as well?
No there were graduate students, but I was there as a post doc, and I used to interact with the graduate students.
No, a group, we interacted with the Lockett group, especially, and with the [inaudible] group. And I remember one meeting at the, what is? There is a center. The, so where it was, whether collision-less shock would exist in space or not. And there was a great debate. And there I met Professor Rossi, who later became my friend. Kind of father at MIT. There was a great debate of that. And the--
What was the debate? What were the different points of view?
Let me explain to you. In the air, you get a shockwave, it's the mean free path is smaller, it's very small. Smaller than an airplane itself. So the shock thickness. But in the case of the solar wind, the mean free path is very, very long. So in a collision-less plasma, you didn't know whether the shock exist.
And theoretically, also thanks to the work done on the hydrogen bomb, they should have existed. But I remember there was a fluid dynamicist whose name I've forgotten, who had computed the short wave in front of the bioshock as if it was fluid. Well, we were skeptical, but experiments showed that there was one later on. This comp -- [crosstalk]
Why were you skeptical? Did it not fit the theory?
No I was skeptical, not it didn't fit the theory, it's that it was difficult to prove that you could have a shockwave. And in fact, to skip in time, a year later, I was invited to work on the plasma physics for the [connection breaks up] program, so [inaudible] on the Voyager when it, for the first encounter with Uranus, and later with Neptune. And the collision shock in front of Uranus was very strange. And I began to work on it, and still now I don't think we have a good theory for it. In fact--
Still to this day, you still don't have a good theory for it?
In fact, you know, NASA every day, I am jumping – during the days of the encounters, NASA put us in front of TV, but we had to say that everything was according to plan. So the fact that the shockwave that we had seen in front of Uranus did not go well with NASA. And they let a paper, it could have been, that is being published not with [inaudible] saying that it was simply fluid dynamics and so on.
Why was NASA-- They were unhappy with the research, or what was their problem?
No, no, no. Everything is to be according to plans. And they did no plasma physics. But now my closest partner there was a German friend, a wonderful person, he was a professor at the University of Iowa. Now I should have written his name. And we were the first two people to see what was around Uranus. It was marvelous, because from the optical point of view, Uranus was clouded, it was very uninteresting. But from the plasma physics point of view, it's very interesting. I think we would need to go back and review the data and so on.
Now let me jump again. When I was at Princeton, I used to have lunch with Dyson. And we had very similar ideas of nature and everything. And so, Dyson, too, was interested in space. But he liked to dream. So when the Voyager – no, Voyager were not supposed to Uranus or Neptune. Was supposed to -- the mission was mis-shot. Then he wanted to somewhat participate, but he was not admitted to Weaver's very strict group, the control room. So he stayed outside with the press. So he liked, he fantasized [laughs].
And another person that you may be interested in was Feynman. Now--
Feynman has a sister. Joan. Sister. Joan was a space physicist. And she was at Boston College in Boston. So she for some reason consulted me whenever problems of plasma physics, so my interaction with Feynman started through her. And I was told this story, I don't know whether she told me, or the story's [inaudible]. One day, they saw, they were in Long Island I think, they saw an aurora one night. And then Joan ask Feynman, he's her brother, to think not to work in space. That he should abstain from work in that field. [laughs]
Well, what happened is that someone, there was a debate with Feynman for years, because the idea of collecting modes did not, you know, collecting modes are kind of quasi-particles. The idea is you get from elementary particle physics or nuclear physics are not valid, and they do some things like, well, you have the superconductivity. But we have similar phenomena, strain scatterings and so on. So for years, we had a debate. For example, he felt it was hopeless to try to go find a plasma. It would be confined in milk with [inaudible]. And so even, I remember, I gave a colloquia at Caltech, but he was not quite happy. But the Voyager thing, he came to see me in the control room, and he said, "Bruno, you should read some phrase in my--" one of his elementary book, that he converted it completely. He realized there were complex phenomena and so on.
What actually changed his mind? How did he see things differently?
I don't know, but he came to the control room one evening.
And the fact that... I give you an example, I don't know if that was the case. The, we were several of us at different towers to work with the Voyager. And so a friend, Norman Ness, was measuring magnetic fields. He was not a plasma physicist, but he was measuring the magnetic fields. So he went ahead of us, must be five o'clock in the morning, but we arrive later because we were interested... We were waiting the shockwave and the plasma around the Uranus. So then I asked, "Now, how was the field?" Well he said, "Of course, it was aligned with the axis of rotation." But then he said, "You know, we know from dynamic theory." But then he told me, "Do you know that the theory's not an established theory? We still don't know."
So I don't know whether, I don't think my conversation, nothing to do with that. But he went back to review the data in the afternoon. And he found that the magnetic field was at an axis. What's off-axis was not aligned with the axis of rotation. So I don't know what triggered the Feynman conversion. And he remained very interested. I forgot, I think he lived until the Neptune encounter that was in 1969. No, '89. But then, before he died, his sister moved. She went away from Boston, she joined him in LA. But he was definitely converted. [laughs]
How do you think that changed his broader thinking, when he decided to change his mind on this?
I don't know. That... But he had the idea, you know, he liked to think in the broader view of things and so on. But at the beginning, he was quite stubborn, let's say.
Was Feynman, was he easy to talk to?
Well, he has his own language. His own intuition and so on.
And so in speaking about that, a great deal of interaction when I was at the Institute, we're talking different ideas, you know.
That's okay. That's fine.
If it is okay with you. With Gell-Mann. And Gell-Mann was very easy to interact. He liked to show, but he was not a showman, he really enjoyed it. He knew a lot about birds. [laughs] We used to walk in the east, and he asked me all sorts of questions, and so I would say Gell-Mann was very easy to interact with.
Now, when you were working with Gell-Mann at the Institute, what was his research at the time?
I was not working with him. We were just going to lunch --
No, I mean as a colleague, I mean when you were interacting with him. What was his research?
[crosstalk] Well he began to go outside of physics.
And he was interested in history a lot. Dynamics of society, and so on.
And at the Institute, you were encouraged to do that kind of thing? To branch out from your own discipline?
Well, yes and no, because-- That came naturally, in a way. But we had a contract with DOE that supported us. Rosenbluth and myself, and we had some other post docs that came. So Rosenbluth was a dear friend, he was close brother to me. But did not like me to work too much in space physics, in fact. But he never put any pressure so that we would not talk about other things. Now, Dyson, we were talking about his view of the universe and of physics. You may have read some of his book, Infinite in All Directions, and so on. And yes, this view which I share, that we are surrounded by mystery in a way. We know very little arcane theory. The Voyager mission, really, brought that home, because everything we knew, you know, had to be changed. And still, you know, I think the [inaudible] know the evolution that Voyager represented, because for the first time we put instruments to see close things that we used to observe with... Well, when I was going to lunch with Dyson, the Voyager had not come yet. But many of the things that he wrote in his book came out from him during these lunches. And so certainly, Dyson was invited to branch out -- but also Wheeler, you know? Wheeler liked to fantasize a lot.
Now, when you say that Dyson was a "dreamer" what do you mean by that? What did he dream about, or how did that affect the way that he saw physics?
Well, he used to have this view... He was, as you know, very strong in mathematics, and so he could deal with anything, really. He had no complex of inferiority with theorists. And he thought about the universe. But for him, also, the space experience was something beyond what he had thought. You know, he began to write this book, you probably know, because he had children. He had to support them to go to college. Otherwise he would have kept his thoughts to his friends, including myself. And so, in a way, it was great that he was in need of make money and he did it with these books. So you know, coming back to Johnny Wheeler, he used to have books with hard covers, which I think they are stored at the University of Texas. Now, if he asked question, he would say something, that's their opinion. He would greatly intimidated to find out what I would say.
And so scared. He was doing it-- he was not arrogant for himself and so on, but it was intimidating. When I was invited to MIT, he came with me to Boston. In those days, there were Eastern Airlines that was flying from Newark to Boston. [inaudible] He had discouraged me to going to MIT, I must say.
Well, in a way, he was right. The... Let me tell you why I went to MIT. Because he felt that probably from the theoretical point of view, his ideas at MIT were not too popular. Something like that. And but I never found anybody against him at MIT. But again, going back and forth with time, when I was at the Institute, that was the spring sometime in '68. Professor Rossi came by. He had a daughter who was in high school in Philadelphia, so you know, I was [inaudible], he was a great man. He was a close friend with Fermi. Fermi had learned from him how to make Geiger counter, and so. But Rossi was not an arrogant man either. So then he asked me whether I would be willing to go to MIT and leave the Institute. Well, I was happy at the Institute. But then again, he told me about [inaudible] astronomy and [differentiating] what we know now to be the heliosphere. At Princeton, you know, Princeton has always been a rather conservative place, except for revolutionary people like Dyson or, or, or... Wheeler was a revolutionary, too. [laughs]
You mean in their thought, not their politics?
Yes, not their politics. You're absolutely right. Yes, I'm sorry for that. I'm glad you know that. And so then, no, Rossi was quite a leftist, relative to them. So then I was so fascinated. And then he invited for me to go to MIT. Give a colloquia and do some meetings. And I found this group, because MIT at that time, with the reputation of the Institute been rather arrogant. But I found this group to be quite... How can I say? Brotherly and sort of open-minded, international, and so on. And I was so interested, you know, in going to a place where they could do space physics. They had gone into space, so then, this is when I decided to leave the Institute.
Yeah. Now the same question, could you have stayed on at the Institute, or it was more of a fixed term?
I had a long-term appointment.
So I don't know when would that expire.
But you left when you wanted to leave? You could have stayed.
That's right. That's right. And also, after I left, not much after, Rosenbluth left too. Now, the Institute, well, let me say, I was very lucky when I was there. Gunther was around, Wheeler would come, and so on. But the fact of being separated from the experimentalists was a drawback in a way.
So there really were no experimentalists at the Institute, by definition?
No. Except they invited, as I said, Marshall Rosenbluth, and me who had been close. I'd interpreted experiments at Princeton, quite successfully I must say.
And Rosenbluth, as you know, he had an important role really in nuclear physics, also the design of the hydrogen bomb with Dick Garwin. And became a good friend of Dick Garwin. You probably know that Fermi used to say that Dick was his best student. [laugh]
Well, more than that. I talked with Dick a few weeks ago, and we talked for a long time about, Fermi allegedly said of Garwin, and this came from Goldberger, I think.
Fermi said that Garwin was the only genius he ever met.
Oh really? [laugh]
So Garwin, Dick spent a long time explaining to me why he emphatically disagreed with that analysis, but it is what it is.
I see, I'm glad to hear that, because I'm rather close, I think, close friends with Dick. I can tell you one reason why, and I see. Well, it's more than what Rosenbluth used to tell me. [both laugh] I have great admiration for Dick.
And he is grateful to me, maybe he never talks about. He wrote a seminal paper with Rosenbluth and his wife called the Snowplow Model. I already talked to you about collisory shock.
Well, that paper is a fundamental paper, not well-known, that was the basis for a first theory of collisory shock that was done by Adler [inaudible] in England. Later. So when I went to Princeton the second time, I was teaching graduate students and so I taught... The Garwin paper's just been declassified, you know? And I taught this theory. And so he's always been still grateful to me for having recognized this strange story from him. They wanted to publish it in the Astrophysical Journal. Now, it's Chandrasekhar was the editor. And I don't know, I think it was before I became friends with Chandrasekhar. Well, Chandrasekhar was very picky. Was very generous as an editor and as a referee. So he did not agree with the symbols of Garwin's [inaudible] paper. So it never got published. But Garwin had said that this one of his important contribution. And he's right. Because collisory shock are kind of started to decay. And so on. That is a very fundamental paper, what can I say that?
So I'm glad that you interviewed Garwin.
Did you consider other departments besides MIT? Or that was always where you wanted to end up?
No. No, no. I was invited by Cornell, where there was a dear friend called Norman Rostoker, who used to be at UCSD, I'd ever talked to you about UCSD, together with Marshall Rosenbluth, and I was very tempted to go there. Another university, there were a number of universities that invited me, another one that tempted me was Wisconsin because the inventor of-- [phone rings] Let me turn this off.
Inventor of the BASIC program, Tom Kurtz, was there. And then in fact he helped me greatly after I went to MIT I decided to start experiments, with Alcator experiments, and Tom Kurtz had a major role. They had made a completely separate [laughs] [inaudible] Nobel prize, but including Tom Kurtz. So I was tempted by these three universities. And also at that time I was still affiliated with UCSD. And so I was very close to Marshall Rosenbluth, as a friend, as a collaborator. So, I had a number of offers.
So why MIT in the end?
Well, I would say because of Rossi, what he was doing. And this closeness to Europe. You know, I could go... Boston is very close to Europe. And I could go back and forth. And also, also here, I found the intellectual community quite lively. I would tell you a few names of people, and so. But let me say, nothing is rich as the, my first time at Princeton admitted, thermo-intellectual. [laugh] Now, through Rossi, I learned a lot about Fermi. Because of Dick and Marshall Rosenbluth, and so on. And there are some anecdotes that sometime – I'm sure, that Dick might have told you – that even preceded Dick. [laugh]
Please, tell me.
Let me tell you some. It's not about myself. First of all, Mrs. Rossi... Rossi and Fermi was quite close for that time in Italy. And one day, Rossi, they ended up in corna-- coming out from Europe, and Fermi likes to visit them. So one day, Fermi asks Mrs. Rossi to step outside the kitchen, and then, but the walls were thin. So Fermi told him in Italian that there was very good idea that a bomb would be built, something like that. And so years later, when they were invited to Los Alamos, Rossi could not tell his wife. And then she said, "What is it? What Fermi talked to you about?" "Oh, it was very secret. Please don't speak about that." [laugh] And so another episode by... I don't know if you know that, but Fermi was invited to go to Los Alamos when Rossi was there. And Oppenheimer was jealous of Fermi. And--
What was he jealous about? What was the jealousy?
I don't know, that is too... I don't know, but I mean, these stories that – Fermi used to go to Rossi almost every morning to go and ask Oppenheimer to give him something interesting to do. [both laugh] And in fact during those days he had made, you know, there was this famous experiment that with the [inaudible] explosion occurred to, that Fermi dropped pieces of paper he computed. He had conceived this during this [laugh] time when Oppenheimer did not let him to do anything interesting. [both laugh] And what the story that Rossi told me is that one day, this [inaudible] broke down so, then they dismantled the machine, this [inaudible] machine. And they couldn't put it together the two greatest… [both laugh]
That's great. So how old were you when you got to MIT? How far advanced were you in your career at this point?
Oh, by this time that I was 33 at that time.
Okay. And did you come on with tenure, or you came on at the assistant level?
No, no, they made me full professor immediately. Because all the other universities had offered me full professorship. I had already done my, at UCSD, and at Princeton.
Now, this question about, you know, when you were given the advice, maybe, not to go to MIT because what you were working on was not respected there, right? And you already--
Well, not respected is too strong a word.
Not as serious?
No, probably, you know, I don't know what to say. Because in the Rossi group, my work – I did tell you, is space physics, [inaudible]. You know, the work we got at the Institute, the idea came up that we could go to as a strong collaboration with Trieste because that was a good place to collaborate with the Russian. [inaudible] And so there, one I remember that was the '65, must be, '65-'66. Rosenbluth felt that work in fusion was so important, and also with plasma laboratory, because we did plasma physics set by experiment, you can do things which are sound. Your theory can be proven, which he was right about that. But so we considered that my temptation to work in space physics sometime could have been too st-- So he went on a cruise with his wife and children. So then I had two French colleagues, Lavagne and Villiers, from l'École Polytechnique.
And then at that time, Norman Ness [inaudible], later I met on the Voyager, I had been in touch with him but don't— forgot about what... You know, I had proposed while at Stanford that the aurora surface storm originated in the back of the earth, and they are the result of a phenomenon that we call our reconnection. So Norman Ness discovered that there was a magneto thing. Then I felt that I had all the theory to write a serious paper and I wrote it with my French colleagues while Marshall was away. It was a distraction. But that was a definitive interpretation of the role of surface storms. Now it is still quite valid, and so on. So that work was known at MIT also. Also that at Princeton admitted theory that interpret... At Princeton, they had big machines called physiocoalescent kill machines, where you could test the connective mode. So I directed an experiment there. And so my work was certainly appreciated at MIT. But not these crazy things, of combining plasma physics in general relativity. Hmm. It's still, at MIT, there is suspicion about-- Now it's called general relativity. [crosstalk]
Yeah, yeah. Well, I guess my question, what I was meaning to ask, is of course, when you got there, the warning that you got did not play out. That your work was appreciated and that it was respected there. But my question is about the reputation of MIT when you were considering it, in terms of what did you feel were the branches of physics that really were emphasized at MIT, and that, you know, the most resources were being poured into those areas?
Well, you know very well, nuclear physics. No question. Now, unfortunately, elementary plasma physics has remained. But nuclear physics is not as strong as it used to be.
Now when you say "unfortunately," why is that unfortunate?
Well, I think it's an important field. And MIT used to be probably first place in the world. Curmon, Feshbach, I could tell you...
And it remained very strong in elementary particle physics. And well, I think as you know, MIT has narrowed in term of interest because of financial reasons, and so when I was there, it was very broad. And but also we don't have any activity anymore in the space physics, in the heliosphere. Where we are pioneer. A great deal is being done at UCLA of that. So the reservation of my colleagues at the Institute toward MIT is to do probably about theory, the fact that these general relativity and high energy plasmas and so on had not... I don't know, I don't know why they pressured this, in a way. In what, the community, I found at MIT was wonderful.
And when you first got there, did you start with a lab right away, or did that come later?
Oh, that's a good point. First of all, there was something funny about the MIT laboratories. And the... So at first I went there, I decided to work with Rossi and his group. And do theory. What happened in those days, was that space physics was very strong within MIT. It was directed by Rossi, and a former student of his, Bridge. Herb Bridge had been with him in Los Alamos. And they work on an experiment called Arala that is taking a sphere and try to collapse it in a symmetric way. And Bridge was a wonderful person, very generous, and so he's the one what put me on the Voyager.
So I worked with Rossi at MIT in space physics, but then he had set up a private company with this student of his, in a lab that belonged to MIT. Now there is a very elegant building, private company, called American Science and Engineering. For some reason, the MIT administration did not appreciate x-ray astronomy. Rossi was always getting back with talking to me about it. [laugh] He never told me the complete story, although we were, for me he was like a father, you know, I was very close to Bruno.
So I worked, I was a theory consultant for American Science and Engineering. And at that time, there was Rossi, he was the founder, and there was Giacconi. Giacconi was very interested in what became known as the Aurora satellite. That then discovered a vast number of x-ray stars. But even before the Aurora satellite, there were seven of them known. Giacconi was a very interesting person. He gave the impression of being a manager. He was a great manager. But he was also intellectual, he believed in black holes. [inaudible] Giacconi. Also later on--
But let me tell you about black holes, the black holes were identified experimentally through x-ray astronomy by two MIT person. One is Ronald Remillard, who is still with us. He's never been made a professor, but McClintock was a graduate student of us, and Remillard, are the two discoverer in a way. So I was very happy with the American Science and Engineering group. And so that this interest in the x-ray astronomy, but also Rossi and Giacconi had conceived the x-ray telescope. And they were the first group to send up an x-ray telescope to look at the sun. So I was around the table when the first image came out. And I don't know, there was some name that were going there, the so-called bright points of the corona and the corona holes. I do not remember where... The principle investigator a collaborator of Giacconi, [Colvayana] who died, unfortunately.
So when I went to MIT, I was mostly interested in that. But of course, the problem with astrophysics is that you're never sure whether your theory is right. With space you could. So then I thought, why not try to use the funding and the knowledge of high energy plasma that exists for future research to do experiment? To study that? Okay? In those days, the head of the Atomic Energy Commission was Seaborg. And the Atomic Energy Commission was quite a scientific institution. It was not like the Department of Energy. And so I don't know why, I explained to Seaborg some friend, [inaudible], who was good terms with Seaborg, so he felt that my idea to do something to try to reproduce on Earth x-ray [inaudible] its own, was a bit extravagant, but why not do the experiment? And that was the experiment that is called the Alcator experiment. And the idea to do experiments of that kind came up at Princeton. When I was at Princeton, we had a group of – before going to MIT, I was spending afternoons at the plasma physics laboratory. And there was a group of heretics. One was John Dorso, was a great friend. He's the inventor of the laser acceleration. Weak field acceleration. He originated that, that we, I thought of high field devices of interorder type.
But when I went to MIT, after I'd gone, I happened to visit the magnet laboratory, and the director introduced me to Bruce Montgomery, an engineer that worked with Peter. He had the technology to make high fields. So a machine I had imagined to do when I was at Princeton, together with Mazzucato, he's a friend. He's still at, retired at Princeton. We could go far beyond what we thought of Princeton, tried to reintroduce the plasma things with x-ray stars, there were just two type of plasmas. One that was seen with the corrupt, on the corrupt nebula. There were neutral plasmas.
And the other was Scorpius X-1. Scorpius X-1 was originally discovered by Rossi, Giacconi, and other ones. You probably know the story. They had gotten money from the army to send a rocket to look at the x-ray from the moon that did not exist, but later were found by the German, by the way. But they look outside and they discover Scorpius X-1. Now, Scorpius and the plasma that was terminal. 4 KEV with density of 10 to the 15th. So then I thought that this experiment would do this type, two different type of plasmas. Those that are associated with black holes, and that was in particular per cubic centimeter. And those associated with the [inaudible] nebula. So this is when Rossi regretted that, Rossi loved me dearly as a friend, and so he felt that if I engaged in that, I would to have had time anymore for space physics or astrophysics. So... [laughs]
Because it was just so complicated? It would just take up all of your resources?
Yes. But also not mentally, you know? Laboratory plasmas are different from the one.
And also you know, in each field you need to make publicity. To have time for the publicity. [laugh]
So, to make the story short, we had good luck in reproducing the neutron plasmas, and in fact, we discovered a phenomenon that was already used by Ginzburg for x-ray astronomy. The scattering by electrons – if you have an electron going along the magnetic field, it can be scattered by a collecting mold. It rotates perpendicular to the magnetic field. And so I'd made a theory. I didn't know about the Ginzburg work. It was very much parallel. Then I became a friend to Rossi with his work. And so with good luck in setting neutron plasmas, but these plasma were very low densities, they were not terminal. Very little interest for fusion, and in particular they were of little interest for black holes. What we knew, that was not a good word to pronounce, by the way, in those days. You should talk to Ray Weiss about that situation.
And so then I went back to Princeton, and I had a friend who died, and [Ed Frieman] was there, he was a very good friend. He had heard, I don't know from whom, that if you put a vault and bleed gas, you make effective plasma. And then, I had an assistant professor, was an experimental genius. He understood, not theory, fortunately, so because theoretical is very difficult to imagine that you create a plasma, at the end, you would go toward the center. And so... But I felt that we should do the experiment, because we'd collected what you could do it. So we did the experiment, and lo and behold, the density went up. Then I made the theory, which is still very much valid, where you can transport due to different collective mode of particles from the edge toward the center. Then this density went up and up and then we ended up to get the densities of the black holes. Now I'll tell you, there is interesting physics. But again, [inaudible] in those days, it's an interesting black hole, but even now that they're popular, nobody realizes, that we admitted many times, realized that we have made them in the laboratory.
And, still you know, if I try to get money at MIT, there is some internal funds, especially in [inaudible] astrophysicists don't want to. Least, they are not like Wheeler, according to this [laugh] general relativity with astrophysics. So, but then continuing the story, Rossi was very happy about that. And Giacconi too, of course.
And when did the Russians get involved in this?
Oh, very early. Let me explain to you. When I was at Princeton, the Atomic Energy Commission decided to send a high level group to Russia. I had work already with the Russian. First I had met them. Perlicov, for example. And then [Sedov and Galenth], in Trieste, we were very close together. We learned a lot of their physics and they learned from us, Rosenbluth and me, about this one. So I was very much connected with the Russian already. So the AEC invited all the directors of the major laboratory and their head of their fusion program, [inaudible]. And I was the youngest invited to go to Russia because I worked with them and so on. So then we visited all the major laboratory. You know, St. Petersburg, at that time, Budker was the director, and now the laboratory is called the Budker. He was an outstanding accelerator physicist. He took us to lake by car, by plane, and so on. So then we were in St. Petersburg, this was called Leningrad, and of course in Moscow, and you may have realized in those days, that was '67, I think, the hotels, there were almost no foreigners.
There were spies all over, you know? Every movement was – But the Russian, in a way, at the private level, were very free to speak out. And so on. So then my connection with the Russian goes deeper. And I got to understand what their work on the tokamak was. So when I went to MIT, I used – The Princeton group did not believe in the Russian experiments And then they--
Why not? They thought that the theory was wrong? What was their issue?
No, they thought that, they had made an accelerator not in plasma confinement. Confined plasma. That their electrons were beams of electrons, super terminal. And so they completely misjudged them. I knew that that was not true, because I had been there. But the situation was the result when the British decided to do an experiment with [inaudible] that would measure the electron distribution. And the actual original topso scattering experiment of well-confined plasma were done at Princeton while I was there. The experimentalists were Demok and Mazzucato, and I was doing the jury for that. So I was quite acquainted.
Now, when the Russian did the experiments, and they were successful, then they sent me to emissary to MIT to tell me in secret. Not because they wanted to make big surprise internationally, and I forgot their name. He came for an atomic physics conference. But I was forbidden to tell Princeton. I tried to convince Princeton not to object to the Russian. But they would not listen, my friends at Princeton, because they still felt that the Russian did not have well-confined plasmas. Of course, by the time we're at the conference in Novosibirsk, that was the end of '68. The British revealed their experiment, that there was no doubt that their... By that time, Princeton... that was '69? Forgot. Yes, I think it was '69. Princeton decided suddenly to abandon the accelerator approach. There, just to go along the Russian, the tokamak approach. That the Russian used, [inaudible] as it's a method within the simple in the accelerator. Where the accelerator had number of advantages, so I remembered both are [in audible] and I objected to that. And that [inaudible] was said in public, no scientist in good faith should abandon that line of work. But Princeton did. And now they go back after many years. 50 years or more.
So in designing the MIT experiment, I decided to use the simplest configuration because what I learned from Asimov, it was a great experiment. You should use the simplest. But I did not use their technology. I had to invent something new. It was a [inaudible] system that would allow you to make very compact experiment, it was high field, so that you could make the densities that I wanted to have for the black holes. And that is called the [paloider] field system that actually Don Kurtz understood. Now, it is in probably all the machinery, the original method, but nobody would know that I had to invent it because of the black holes. [laugh] And not the eater machine, you know, is a gigantic system of that type.
Now, the Alcator program, did that lead directly into the Ignitor program?
Or were those separate?
No, no, no. It led directly. What happened is that when we began to do the densities of the 10 to the 15 particle per cubic centimeter for the black holes, a Russian friend called Pedrov, one night came to the office. His eyes are bright, saying, "Bruno, do you know that those plasmas are pure?" So then we discovered that those plasmas, very high densities, were pure, that you need to just use your reactor are well-confined. So shortly after that, I began to think of doing an experiment to prove ignition. And that--
And what does that mean, Bruno? What does that mean to "prove ignition"?
Oh, that's a good point. There is a point where the charge fusion products deposit enough energy in the plasma to compensate for all the losses. And the only experiment that could do that is the high field, high density experiment. And when I proposed it, you can imagine there was a storm. Because the idea was, it came from Princeton, even from my friend. That you could only reach ignition with a gigantic expended cost, huge amount of money. And well, even my Russian friend, he was a great scientist, Kadomtsev came to me and said, "Bruno, that idea deserves the Nobel prize, but it's totally useless for fusion." Well, I told him, after all, the Alcator was then to reproduce the black holes, and that would be basic physics. But by now, people have realized that you need to get close to ignition, that it's not just an academic goal, and to have an experiment or a machine with a system that could heat it up to ignition would require enormous system. So now, the official line of the US is that the first pilot planes should be of the compact type. Like [Degnetor]. And but I must say with some bitterness, the DOE that succeeded [inaudible] doesn't have the same scientific standards. The Alcator program was for some reason a kind of, and even my theory put me heretical. [crosstalk]
So you saw that change right away when the Atomic Energy Commission transformed into DOE? You saw that degradation in scientific knowledge and appreciation right away?
Thank you for telling me that. In fact, I can tell you a real story. In that time, I was walking around the corridor of MIT, very worried, and I met Jerry Wiesner. Jerry Wiesner had been a science advisor to Kennedy and so on. And we had worked together also, with the Russian, on issue of disarmaments also. He said, "Bruno." He stopped me. "What do you think?" "Well," I said, "I'm very worried about these things." He said, "I'll tell you something. If you put a little bit of good wine into bad wine, you will get bad wine. And this is what happened to the DOE. Unfortunately.
And I wish the DOE... I think the military part of DOE fortunately worked and administered the ignition experiment.
As their main scientific [crosstalk]
So let's say the Atomic Energy Commission continued, and it wasn't the DOE. And the frustration that you felt with the DOE, what would you have been able to explain to the Atomic Energy Commission in this alternate reality that would have ensured that they would have supported you fully in this?
Oh, just what I would have done, like the Alcator. Shown them there's physics to discover.
And that was a good line to work. If you don't establish sound line of physics, you know, in correcting most, as important as elementary particles. You know, unless they are good collective modes, when you have... You know, it's a [inaudible] when you have a fusion burning plasma. It is not like the hydrogen bomb. You could do with a lot of thermodynamics and so on. Here, you are outside of thermodynamics. Okay, it's a very delicate balance of processes. So there was plenty to be discovered. But I think with Seaborg and so on, I would have had no difficulty to convince him.
And what exactly did you need from the Department of Energy? Was it just funding? Did you need instrumentation?
Well, I would say encouragement.
Mostly. Because there were some people like Trivelpiece there, he wanted to do an experiment of that type at Savannah River. And he still, he told me, I saw him recently, that, because he's a good friend of Velikhov. That he wanted, but I don't know why he was not listened to. I mean, his point of view, old guard, it was scientifically-minded. The DOE was so naive that you could do a commercial power plant without learning the physics. And that turned out to be, you know, misguided.
What would you have liked the igniter program to accomplish in a perfect world?
Well, again, first of all to discover the plasma collective modes that you – Another process which is quite important are self-organization processes. Years ago, in 1980, I wrote a paper that became confirmed with experiment, that shows even in elementary switches, deuterium, deuteron, an electron plasma. It's very elementary. You get self-organization. Now, the theory for that is an [inaudible]. And you know, self-organization is everywhere in nature. Including in biophysics and so on. So I think we could have learned a lot from a plasma where nuclear reactions are important, nuclear physics is important, and so on. And the collective modes.
Is this a lost opportunity? I mean, can the research be picked back up?
Oh yes, but by the way, it never stopped.
Because what happened, I set up a pilot program in Italy called the Frascati Toros.
That's been very successful. But of course, I must tell you the story of Italy for years' time, the... It had ended up in the hands of the European bureaucracy, tried everything to stop [inaudible]. But we had special money for us that protected us from the European bureaucracy, and I had a special friend in Russia, Velikhov, and so we started a collaboration with the Russian. So the program never stopped. We have an ongoing collaboration. The present, it got slowed down.
So we have a very strong relationship with Russian, though. [inaudible] now is the most successful nuclear industry in the world. Officially, at least. So they have built the facility to house an ignitor type of experiment in Petrovsk. So we are connected with them. Then, you know, this is a very coveted idea to use the physics and the technology of [inaudible], with no extrapolation, as a neutron source to make a reactor hybrid without deuterium. And that is another connection to the Russian. Except we have many friends in the US, including with the DOE, that secretly support [laugh], not money-wise.
One friend from DOE, I cannot name him, he had a good idea to make a hybrid reactor with deuterium that this, with the high-fill technology, we could do TD burning experiments. And possibly reactors. So DD source of neutrons with, we don't need to use tritium. Combined with thorium can be a very attractive reactor. Now, there is no reason why you should not do this with the [inaudible] as you do it with the Russian. [laugh] I think if we had continued with the AEC, we could have proven or disproven, we could [connection breaks up]. We certainly would have made hybrid reactors.
Yeah. What was it about the Frascati Torres program that attracted you there? What were they offering that you couldn't do anywhere else?
Oh, well that's a good point. The, first of all, the idea of doing an experiment in Frascati came up before I came to MIT. What happened is that during the Novosibirsk Conference, I was a guest of Budker. And but he asked me there had been problem with find the hotel and so on. So I was very embarrassed to accept the invitation of Budker to sleep in his house. So the director of the Frascati Laboratory said, "Why don't you use [inaudible] share a room with me?" And then we thought together to do an experiment of the tokamak type at Frascati. But I did not have the idea to do the high field. That came later. Later the, so what attracted me was that the... In Italy the technology for electrical engineering combined with mechanical engineering was more advanced than in the US. Because the US abandoned, like they abandoned other type of classical technologies, and so on. So from that point of view, it was a good. And this is what attracted me to study, also to have another experiment that would replicate the Alcator results.
But that was fought by Brussels. Because Brussels felt that, you know, it was too much of an imitation of MIT, and then very soon, I will tell you the story of ether. [clears throat] They took control of the ether program. It would disrupt the ether program, and so. But in the advantage of the Italian cooperation – besides the fact that the Frascati Torres machines had been a success, because they illuminated more physics than the Alcator – is that we completed the design. We have a full design and the prototype. So we proved that you could do an experiment to prove ignition. This doesn't mean that you erase it. You see? Because a [inaudible] plasma, is highly self-organized, the alpha, the fusion product heating determines the density and temperature provided of those plasma. And those determine the collective modes. It's far more difficult in the [inaudible].
Now, one day, there was a colleague, she's from Harvard, used to be the head of the office of science at the DOE. She asked me, because she gave a talking saying that we, our codes have so completed, we can simulate the ignition in a confinement experiment. And I said it's conceptually possible. Because even without nuclear physics, you have to work in with seven dimensions. It's very... You have no thermodynamics. But then she asked me, "What about simulating the hydrogen bomb?" Of course, there's 1000 shots. But we don't have anyone to, this far more difficult. So having accomplished the design and so on, of the machine, I'd build pieces. It's already an achievement.
What we did not expect, that the big bureaucracy that would emerge out of the ether program would be slowing down. You know, the fusion problem was basically stopped because of ether.
Yeah. Yeah. I want to go back to your work on Voyager 2. So my first question there is, what was that connection? Were you aware of the plans for this, and you wanted to get involved, or did somebody there ask you to join?
Okay, let explain to you. First, something sentimental in this, and it's a feeling shared by everyone in the Voyager group. It was a great experience for us. Of humility. Now, what happens was that the Herb Bridge, was a student of Rossi, was in charge of the space program at MIT. He was an experimentalist. He has put instruments in all, how can I say? Missions concerning the heliosphere. And including now, there is the so-called "Parker Probe." The Parker Probe, that is a far-away [inaudible] that Bridge and Rossi had invented. It's being used now, so. So then he came to me. He said, "Bruno, I'm getting old. You know, you know plasma physics. I think you should come on board, we need you." So but also, it was an act of great generosity, because you see, I had done nothing. And I was given the gift of those results of being – we were two people to see Uranus for the first time. And later, Neptune.
And in fact, I was hoping to be alive between Uranus and Neptune, because to relive that experience. And the one experience you might be interested, is, I think we had to wait for, I think five hours, waiting for the signal to come from Neptune to us in the control room. That was a strange feeling. You understand, that you are waiting for the light to come. [laugh]
A lot of anticipation?
Yes. Lot of anticipation. So later, I was invited. We continued those meetings at Johns Hopkins. At the Applied Physics Laboratory. And then I gave a talk, I happened to speak about my experience, and a person arose at the end and said, "Mr. Bruno, don't you remember, I was too on the Voyager." And he felt the same. He had the same feelings. It was a human experience, which – And as I said, I did not offer to go. I was just offered the gift.
So I want to ask, Bruno, they wanted you to come on because of your expertise in plasma physics, so my question is: what did your expertise offer the group, and what did this mission offer your research? What was the exchange of benefits in this partnership?
Well, for example, the theory I've done on the aurora. We continued that. And we continued that with the applied physics laboratory. The theory of shockwaves. Except we never published it. We still, [laugh] we're still not sure about that. And... It’s very difficult to say. It's mostly, it's been a human experience.
What do you mean, "a human experience"?
You know, remember, I was this in [inaudible], and what we saw was something very different, I can tell you the details. For example, according to the theory that I was teaching, and there are still people teach, these collisory shocks are solid things. And the [inaudible] sort of was developed during the development of the hydrogen bomb, by the way. And the, according to the theory that I used to teach, the oscillation of the plasma [inaudible] of the magnetic field, it should be equal. They were not. And that, it means that there were different processes. And this is why I never published it, the paper. It still remains to be discussed. And the plasma tense defect, that the magnetic field was not aligned, it meant that the tails of that system had not, like the one of the Earth. They seemed to be, at first we thought they were double tails or, I was the expert for [laugh] magneto tails and so. So, but again, even that one, we have qualitative results but not quite. And I can say that the plasma physics by the Voyager group was quite, not all of them, not by the APR group, was probably underestimated. There is a great deal – I think we need, we all agree that we need to go back to the data and review them, according to what we know.
I want to ask about the differences between the encounters with Uranus and with Neptune, right? So the first one with Uranus, it's obviously, it's a brand-new experience. You're really operating in the frontier. So part of it is, you just don't know what you're going to find out, right? So--
My question with Neptune is, what did the encounter with Uranus teach you and the Voyager 2 team to look for in terms of what to discover at Neptune? What was the value that the mission at Uranus gave you for looking at Neptune?
I, thank you for that question. First of all, we were expecting – The main thing, I would say, the effect of the magnetic field was also, you know, we've had the moon. With very strange plasmas, with a Maxwellian distribution. We did not expect that. I think the 60 kilovolt. Very strange. How does this nuclei thermalize? But the human experience, let's say-- So. What came out of these magnetic field, like in [inaudible] was not aligned, was disaligned but off-set. So, it's as to have the same complex structure as the... Now, what happens with Uranus, let me see. My partner, which I've forgot my name. He was a professor at Iowa and a student went nuts, and he killed five professor, including my friends. So my friend was not there with me second time. But, I'm glad you asked that question. In a way, the greatest experience from your point of view was Uranus, not Neptune.
We were delighted by... Problem with Neptune, you know, was farther away, it took a small time to wait for the signal. And also, there were more people in the control room. We were only two of us in those. [laugh] And in the Uranus side. But someone's, we got more prepared. We were more people, this was more popular. I think Dyson had come back with a price. [laugh] I mean I can't fantasize what we have seen, and so...
Yeah, yeah. Did you think at the end of the Voyager 2 mission that there were going to be additional projects that you would be involved in? Or did you see this as a self-enclosed project?
No, I was expecting to do more of that. I was quite disappointed we did not do more.
So what happened? Why not?
Somewhat, people, except those of us that were in that control room originally, that had that great human experience, we did not transmit that feeling. And now there is something similar going on with the solar probe. There is a graduate student of mine at UCLA called [Melly]. He's in charge of the theory. And that, it's a very good group. Another one, oh my god, it was from our group, he's another university's cutting the experiments with the.... Bridge and Rossi [inaudible]. They have some of the experience that we have with the Voyager, but I think we should have done other missions of that type. [crosstalk]
Was the appetite there? Was the appetite there for NASA?
Was the appetite there from NASA? Would NASA have liked to do more?
Well, NASA did not understand. NASA was very generous with me, I cannot complain. But the fact that we had discovered something quite extraordinary with Uranus, had not been appreciated.
Because your team had not communicated effectively what was that you had discovered?
Probably. See, most anything, we're a group of friends. And some of them I don't know. Bridge was older. I'm sorry that he died. Probably he would have been a great help to convey those feelings.
I want to ask you, during this time, in fact, between the two encounters, you received the Maxwell Prize in plasma physics.
And I'm curious, what did that mean to you? Both personally and professional, to win this prize?
Well, I was delighted to receive it. Also, I had the prize for excellence in plasma physics because of the Alcator and other ones, a number of them. And well, I was very glad.
Did you feel it was useful to you professionally? Did it help your reputation in terms of the kinds of projects that you could be involved in, or the kinds of funding that you would receive, or did you look at it simply as, it was nice to be recognized?
It's a good question. At the present, with the DOE, the fact that you have done good work scientifically [laugh] quite skeptical. If it wasn't that the AEC spirit, I don't think it helped me too much get funding. And... I think the support of my colleagues was very important.
Mmhmm, mmhmm. So I wonder, Bruno, if we could talk a little bit about your more recent research? The kinds of projects that you've been involved in, in the past decade?
Yes. Well, the... I give you one example that came up, I'll say, from the experiments, is that if you make an experiment with a [inaudible] plasma, the plasma rotates spontaneously. And so I called it the spontaneous rotation. Then it was renamed and so on, but something that interest me because this is to do with astrophysics, is the transport of angular momentum. So I've been working on that. I think I have the first explanation. And the first explanation is that the water basis, that the angular momentum is created at the edge of the plasma column, because you inject it. And then the plasma has to counter-rotate. But you have to carry it toward the center. And the funny thing is that the velocity profile is peaked toward the center of the plasma, so you need a process to carry the angular momentum inside. So I use the same theory I use for particle transport. And it has been successful about that. So I've been interested, angular momentum is very important, you know, in the universe. [laughs] You go from the spin of elementary particles to galaxies and so on.
But it's strongly-conserved. It is highly neglected. For example, if you want to make a collision, you have to export angular momentum in the plasma surrounding black hole or this disk and so on. So I've been involved with that. I worked also, where you have magnetically confined plasmas, you have particles that are not secured, but they are trapped. Have strange orbits, and so you have trap particle modes. So I published a paper to know everybody [inaudible] had not been working on that one. Trap particle collective modes. Also things, just successes, the self-organization that predicts that no matter what you do, the profiles of the plasma pressure of the electric temperatures tend to be invariant from one experiment to the other one. We have no theory for that. But self-organization is a mission before, it's very important.
I want to ask, Bruno, about your career in teaching and as a mentor to students. So first, as a mentor to students, can you tell me a little bit about some of your most successful collaborations with graduate students and who among your graduate students you're most proud of, in terms of what they've gone on to accomplish?
Oh, many of them. Some very good ones. For example, I give you one that recently came to the attention of the, he's Brazilian. Ricardo Galvão. He worked with me and with Rosenbluth on a paper that had to do with the internal mode, it has to do with magnetic that they have seen in all experiments. And he was a very bright student, but he working very little, he he could accomplish a lot. I always admired. He became the head of the space program in Brazil, and he took a standing what is Bolsanaro, the head of their government, of the program of Amazon and so on, that he was fired from his job. He took a stand. So he's upstanding as a scientist but also as a human being.
And another person, as I already mentioned, but I have a number of them who have been doing extremely well. Is [Ellie] at UCLA, he created outstanding space physics group. But now, I was not prepared for the [inaudible]. I had some fantastic students.
And what about your teaching of undergraduates? What kind of courses did you enjoy teaching the most?
Oh, teaching undergraduate, my [inaudible] is not, I used to teach a recitation, together with other senior colleagues. Now, our department, whether, I mean, my best experience is with the quality of these colleagues that we work on recitation. And again, I was very lucky. I had very good undergraduate students.
Yeah. And what kinds of courses did you teach? What were your favorite topics to teach undergraduates?
Electromagnetism for example. Yeah, that was.
And at MIT, were most of the students that took your class, were they physics majors?
Yes. Then some of them went into engineering. They were physics majors mostly.
And what kinds of advice would you give undergraduates who were looking to develop a career in physics?
Oh, to do something different. [laugh] I learned that from Wheeler, and Dyson, and so on. And now, people realize, in fact... A friend of mine, you may have heard his name. He just died recently. He was kind of brother to me through MIT. Becker, Ulrich Becker, he's the co-discoverer of the J particle. We were very, very close. And he felt that we were somewhat doing too much of an alter-Manhattan Project. Somewhat. That physics had too much trying, you know. Did not branch out of the spirit of that type of research. So I encouraged Rosenbluth that with me and Wheeler and so on, and Dyson, to work outside of so-called "mainstream." But you know, the familiar zone goes to, still to the so-called "mainstream."
Right. On the question of, you know, I mean, you've had the privilege to work with some of the most incredible people in physics and in the last, you know, 50, 60 years. So instead of asking a simpler question like, "Who was the greatest genius of anybody you worked with?" I mean, however you can rank that. I want to ask you, how did you know that you were in the presence of genius when you were talking to these people? How did you see the mind of a genius at work, and how did you know that it was genius that you were experiencing?
Well, let me say first of all, part of my great luck is that none of these people were arrogant. They did not behave like geniuses. But of course, deep inside you, you know. But I can say that one of my, I really was lucky. You know, I need to go to the list, the long list of people that I put down.
But I think I've interacted with Dick Garwin. If you speak to Dick Garwin, he doesn't try to impress you with being a genius. But he is. [laugh] Or if you know... You know, for example, Wheeler. He used to have coins in his desk. And if you find an error in what he was saying and so on, [laugh] he will give you a coin. Not all-- Small error, would give you five cents. If you make this big error, he would give you 25 cents. [laugh] If you hit his paper with bullets full of errors, [inaudible]. So, also, let me say, [inaudible] was a genius too, but he too, he was not arrogant.
So maybe you realize later, but the fact that these people are geniuses, [inaudible] was not, was a genius, but he did not show it anyway. Last time I saw him, I was at the University of Chicago. It was winter. And they had tunnels between – so it was a bit dark, and then he saw me, and then oh, he said, "Bruno, how glad I am to see you, because nobody talks to me anymore." [laugh] So, as you say, these true geniuses, and he was a genius, they don't show it. And I mean, for Giacconi, he was a genius in his own way, but he gave the impression of just being a manager.
Why do you think that is? Why do they all share this trait of not acting like a genius?
Because they are real scientists. And they know that [laugh] we are far more ignorant than we--
Yeah. Bruno, do you see yourself as coming from a particular intellectual tradition in physics? Like, your field of study and the way that you do your work, do you see that coming from a particular line of physicists and the way that they did their work and how you carried on that tradition?
Well, whether I carried, I don't know. But certainly, people like Rossi or, you know, Dyson, Wheeler, and so on, they have a very strong impact. And whether I carried their tradition or not, but. They were able to branch out through what they did, and to encourage you to think differently. Even though, you know, usually, your paper get rejected if it is original. [both laugh]
I want to ask you a very broad question about your contributions, right? So all the work that you've done in plasma physics and astrophysics and fusion research and space physics, do you see these sub-fields as, are they truly distinct, or are they all sort of part of a larger interest that you've been pursuing your entire career?
Well, thank you again for asking that, because I think there are, I see the unity. I don't see a distinction.
You see the unity?
So what is that unity? What connects all of these fields [crosstalk] at least insofar-as the kinds of work that you have done that connects all of these areas?
Well, I was not prepared to this, but I would say the ability to connect these small world, which is very important—
—from nuclear, elementary particles to the grand scale of the universe. You remember, the cluster of galaxies, at the beginning they thought they were cluster of galaxies. But the biggest objects in the universe, they are mostly plasmas. [laugh] Okay. So, I'll take the issue of angular momentum. It goes from the spin of particles to... There is a unity, but also, this is what I learned from the Voyager experience. That what is beyond us is far more mysterious than even we could imagine.
And what did you make of that?
Well, it's a kind of real humility. I think since you talked to Dick Garwin, I think he's deeply very humble. I'm sure of it.
Remember, he was the first person to design the hydrogen bomb with a slide rule. [laugh]
Yeah. So Bruno, let me ask you an even – a question that you might even be less prepared to answer, but I want to ask you anyway, right? So your contributions, when you put them all together. And we've been speaking at a fairly technical level. And people will learn from this interview that, obviously, you're not only a plasma physicists, right? So I wonder if you can explain in sort of plain language, right? How your work in total has advanced the way we understand how the universe works.
Well, the fact, to bring out the importance of collective modes. You know? This is why I connected very well with Ginzburg. Ginzburg, I began to become friends with him. He came, we watched together the landing on the moon together with Rossi. And so he had discovered independently of me, or vice versa, this collective mode that give you the scattering of electrons and so on, that goes on at the macroscopic level, as well as the microscopic one. I think this idea, too, that collective modes, self-organization. You know, people believe that thermodynamics is the law of the universe. It is not. It's enough to go into space. But even my friend Becker the co-discoverer of the J particle, he worked on metrology. And then he had realized that they create the states of metals where they would not be relax. So using the conserved thermodynamics, even on Earth [laugh], they were not valid. And also what surprises me, these arrows that exist in the universe. It's quite extraordinary, it's a surprise in a way.
Were there any research projects you were involved in that really caused you disappointment, that didn't turn out the way that you wanted to? That you might have done differently had you been given another opportunity?
Well, of course... Well, for example, the Alcator. I was hoping, I designed the machine in such a way – I told you, the astrophysics role was the primary one. But that you could study both the increase of the plasma temperature with collective modes and collisions. And that, the one with collective mode did not... What came out, there were processes that did not increase the terminal energy. Now, a friend of mine started an experiment at the same time. Dramon, at the University of Texas, based completely on the collective mode, and he failed. So that part-- But I did not regret it. We discovered something else very interesting. But the fact that we did not discover the increase of plasma temperatures due to collective mode was a failure. Probably not of mine, it was a failure of nature. And that route was tried by other groups. There isn't, it doesn't work, actually.
In thinking about the way the universe works at your level, right? Do you ever allow your mind to wander into more spiritual questions? Not just the how, but the why? Why things are the way that they are?
Well, Becker and I shared this point of view. We have no answer to this question, but the fact the universe surround us by mystery. And also, how do you explain the existence of evolution in nature? Or the fact that the, some flowers, they are organized in such a way there is a Fibonacci rule in some of the seeds? Then it, maybe it causes some deep questions. We have to face them.
And how do you face them? In the sense that you're a scientist and you're always basing on evidence, but how do you face them if you understand that some things are not based on evidence? Or cannot be understood, I suppose. Or cannot be answered.
I hope that eventually we may understand, but there is far more that we cannot understand. Even Pascal says, he said that our intelligence is not complete unless we understand there are things that go beyond what we understand now.
So you accept the idea that it's possible that everything can be known?
Mmm, probably not. That's a difficult question. What I accept, the idea is that there are things that go beyond our knowledge. Maybe the... we could never have expected what we have seen from space, for example. That was... I already mentioned the cluster of galaxies that we used to believe there were, and they are not. And... [crosstalk] we also—
Where do you-- Yeah, go ahead, please.
One person that I still have a good relationship is [Anopensius], who discovered this [inaudible] C and B. That was a total surprise to him. And how you could have imagined that something that had been speculated was real. Something like that. Let me say, things go well beyond what we know. And our expectation.
Do you ever think about how your work may or may not contribute to a grand, unified theory?
Well, I've never been that arrogant. [laugh] But I don't think, the grand unified theory maybe the, you know, we have great respect with general relativity now. Before it was not. But general theory contains only B and G. There is far more in nature than that. Now, I think a grand unified theory has to go well beyond general relativity. And of course, quantum mechanic is very important, but if we go beyond these two...
You know, I'll give you one example that, somebody, I gave a talk on plasma astrophysics, and then an old professor said, "But let me, how is it possible that gravity and electromagnetism can compete? Electromagnetic forces are so much bigger." The point is, they're so much bigger that they create – they cause the charge separation is very little, so they just separate in such a limited way, that gravity sort of forces are still important. So, maybe this quality obsession, idea to try to combine general relativity with nuclear physics, quantum mechanics, and plasma physics, maybe it will have an impact. I'm sure through my student, having transmitted these ideas, it will have an impact. But what you said before, namely, real scientists are not arrogant.
Right. And part of that, I suppose, is, if you appreciate all that you know, you appreciate all that you don't know.
So in that vein, what remains mysterious to you? In your own understanding of your field and of plasma physics and how the universe works? What are things that are knowable but–
I think I would like to know more, the role of angular momentum. Because people speak about fireballs of the universe and so on. Well, how did things begin to rotate? And to rotate in such a way that you conserve the total angular momentum? And how it... I think it's a small amount of knowledge, but I think that is probably one of the most urgent one.
And what would it take to push forward and discover these things? Is it more about budget? Is it more about technology? Is it more about the right person having the right idea at the right time? How do you see these things working together?
I think mostly, I think to convince people that these are important issues. And you can conceive experiments on Earth, whenever you make... begin to do that. I told you, for example, the fact that the transport angular momentum in the direction were, the frequency increases of rotation. That is very strange and collective modes are important. So, the transports of angular mo-- I think this is a rather elementary process, but that is, would need to be... You need to convince some people to think about it.
Yeah. So, Bruno, you've emphasized this throughout our discussion, the importance of conveying the research, right?
So if you can speak a little bit more broadly, beyond your own experiences, what advice do you have for people that want to do this? How should science be conveyed, and who should science and scientific research be conveyed to for the purpose of scientists achieving the kinds of projects that they want to work on?
Well, I think we should connect, probably, this was lucky to do with people whom you call genius, creative people, that thinks outside of the box. Now what had been missing is that, you know, because of the last bureaucracy – we did not speak about that, I intended to talk to you – what happened in Europe and Russia and also the US, the establishment of the big bureaucracies. This connection between the people doing scientific work involving science and thinking. And the, more than the funding, I would say this had been kind of compromised. There is a well-known writer from Harvard, I think he's [inaudible] is his name? He pointed out that while the faculties had been more diversified ethnically and so on, the uniformity of thinking in science has narrowed.
And I had proposed that to the American Academy of Science, and they accepted the idea we'd probably make a study group for that. The advent of the big bureaucracies had been a tragedy of the last decades.
So to answer your question, I think there's no problem to talk to the Dysons or the Wheelers and so on. But then how do we go beyond those people? [crosstalk]
How do we?
How do we go beyond those people? That's the question.
Yeah, that's right. That is the question. Probably some of us should do like Garwin, spend more time on policy. But as you know, you know the case of the coronavirus, people don't like to listen to scientists. For example, fusion research around the world, even now, might cost $65 billion, or at least, and be done. Well, we have very little to size at the beginning. Relating all of that but the big bureaucracy did not listen. So again, in space, we would need to speak about making cheap mission to go back to explore what is around Uranus again, maybe... It's very strange that there is nothing.
Yeah. Well, Bruno, I think for my last question, I want to ask you something that looks towards the future. You know, for you personally and for the fields that you represent. And that is, what are you most excited about? What continues to motivate you to be active with your work? And what are the kinds of things that you want to achieve personally, and what do you want to see your field achieve in the future?
Well, I give you an example. One is the physics of burning plasmas. Because they combined the collective modes, they're outside of thermodynamics, self-organization. I hope that what we learn about self-organization in plasmas can be transferred to our working in biophysics. For example – you might find it funny, but by listening to the biophysicists – I used some of the idea that I've gotten from plasma physics to construct simple model for the propagation of infection. And I think I found that it can have explosive, by combining real, I mean, geometrical space with time, you can get explosive behavior and so on. So what we learned about self-organization, something simple can be transferred to other fields. I think, so, again, the burning plasmas, they give you. Then the other ones, you know, with LIGO, we discovered the importance of binary systems. We knew that they existed before, but they can be a pump for plasma collective modes, acceleration processes, and so on. I've been writing not many papers, but they will certainly be rejected by the major journal. But I think there's the risk, you know, the multi-messenger approach, which is popular with the, let's say, from the point of view of publicity, but not practice.
It's a very important, this is what I would like to see flourishing. I hope to contribute something to that.
And what would you hope to achieve in this area?
Well, I've been writing papers. For example, if you have system, let's say black holes, with satellite. Black holes are binaries. You have a mechanism to produce high-energy particles. We don't need beams. In fact, experimentally, it was proven that beams are not always there. You know, they exist in one of three regimes of emission from black holes. So you can explain, for example, the... probably know that with the object identified by LIGO, there had been a great lack of correspondence of object found in the x-rays and gamma ray, which is very strange. In a collective mode, you can transfer energy from high-energy particle to low-energy particles, and that we do with fusion plasmas. You can transfer energy by collective mode directly, from the fusion products, let's say 3.5 MEV to KEV particles. So then we could explain why you don't emit from those black hole, why that you don't make an energy emission. That's a big mystery. So I think the role of collective mode-- Now, if you go and propose that those say, not that you are nuts, but not in Russian journal, I might say. There is still a great tradition with. I think I did not speak to you about my interaction with Zeldovitch and so on.
No I didn't.
Well, [inaudible] is the equivalent of Dick Garwin. He was a true genius and so on. He made a lasting impact in chemistry and so on. And he left an impact on Russian science.
So coming back to your question, I think bringing out importance of collective modes in explaining phenomena, which is very strange, those connected with the LIGO observation.
Well, Professor Coppi, it's been an absolute--
[laughs] No, don't call me Professor. It was a pleasure.
Dr. Coppi. Bruno. [both laugh]
It's been a delight talking with you. I'm so glad we were able to do this, and I thank you so much for our time together.
Thank you, again.