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Julius Tabin’s Interview

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Julius Tabin was a physicist and a member of Enrico Fermi’s team at Los Alamos that developed the world’s first atomic bomb during World War II. Tabin, working alongside fellow physicists Herbert Anderson and Darragh Nagle, carried out experiments under Fermi. In July 1945, Tabin witnessed the Trinity Test and afterwards went into into the crater left by the blast, riding in a specially modified lead-lined tank to collect surface samples at ground zero. In this interview, Tabin describes in great detail the personalities of Enrico Fermi and J. Robert Oppenheimer. He further elaborates on how the scientists at Los Alamos got along and the problem-solving strategies they used. Tabin finishes with a reflection on technological progress since WWII and his family.

Date of Interview:
September 12, 2022
Location of the Interview:


Michael Lewis: Julius, tell us a little more about some of the personalities at Los Alamos. First, I know that you were very close with Enrico Fermi. Give us a feeling for what he was like as a person.

Julius Tabin: When I knew Enrico he was in his early forties. Unfortunately he died at an early age from stomach cancer in his early fifties. He was in his early forties when he was at Los Alamos. He was one of the great minds of our century. He was quite unique in the physics area by being not only a great experimentalist, but also a great theoretician. And he had numerous papers, which are landmark papers in both areas.

In general you have theoretical people like [Albert] Einstein or [Niels] Bohr, etc. or you have experimental people and he was good at both, which made it very, very interesting. For the most part we were his— I mentioned the people previously there had been three of us— were his personal team for carrying out experiments that he was interested in or we were all interested in. But Enrico had the position at Los Alamos, I mean scientific director, but the head of the science both theoretical and experimental. He did have a theoretical group separate from ours but when he wants to do any experiments, we would discuss the experiments we would either propose it or he would propose it.

We would jointly agree on what we would do, we prepared the experiment and got everything ready, and carried out the experiment. Generally, he was in the initial discussions. He was not with us when we were constructing the equipment or putting the thing together. When we were ready to take measurements, he would generally come down. He would be there with his little slide rule and it was very effective because we would be running an experiment, we would be gathering data, you would be looking at the data and calculating.  And we’d say, “Now wait a minute something’s wrong. Something must be out of place. The measurement isn’t coming out right.”

Whereas normally you wouldn’t really stop the experiment. You analyze data, if you find out something was wrong, you’d think about it and you’d come back later you were right on top of it. He was recognized by both the theoreticians and experimentalists as being very superior.

I think there were others that were almost as good, but I think Bohr was probably his superior in the theoretical area. He was not an experimentalist at all. Hans Bethe was a very good theoretical person. They had certain good qualities and was an experimentalist. Luis Alvarez was an experimental physicist.

In terms of Enrico you asked [about] his personality. In his social life, he preferred younger people than people who wouldn’t say he was old at forty. But we would all go skiing over the weekends. Enrico would join us. We would go hiking and Enrico would be with our little group. Our little group was quite a tight little, small group, not that we isolated ourselves. We did a lot of things together. Enrico was part of it.

Lewis: Was he light-hearted socially? Was he very serious? Was he fun to be around? 

Tabin: He was fun to be with. He ran a very controlled life. Normally he would go into his office at 9:00, 9:30AM. He would close the door and he would work until the end of the day, so 4:00PM or 5:00PM. He would come out and he would join us for dinner or what have you and he left the work behind him in his office.

But the work in his office, he would say— he would tell us— that in his younger days (and now he was forty), in his younger days he could turn out a paper a day that was notable. He had that power of concentration and did not want to be disturbed when he was working on his own. But when he closed the door, he didn’t spend his evenings thinking physics. He would answer a question if you asked him a question, but he preferred to talk about events of the day, the world, world economics, etc.

In his younger days, clearly he had a total recall of everything. When I knew him in his forties he had one little notebook that he wrote down certain equations or things that he wanted to be sure he had at his fingertips. Except in his younger days he didn’t need that because he knew everything. He could read.

I was with him one day at the Faculty Club of Chicago where there was a botanist. They got into a discussion about some plants, etc. After about a half hour of the discussion, this professor, “Professor Fermi,” he said, “I didn’t know you studied botany.”

Enrico didn’t study botany. He picked up a book one day and he read the book. He could recite it. He was a fountain of knowledge of all kinds.

I remember once we were out at the Points here in Chicago swimming. Somebody just casually wondered to what extent the lake rose and fell with the tides. You see Fermi think for a few seconds and he comes out with a number so much. “How do you know that?”

He said, “Well with the formula for the tides in the lake—” and such and such, and then he recites a big long equation. When you have that kind of a mind, it makes for a very interesting person who is very advanced at lots and lots of things. I think to some extent he liked to show off a little bit, like all of us do. But I found him a fun person. You like him.

You play tennis? When I first started back here out of law school came here we joined the little group we had. Darragh [Nagle], Herb [Anderson], and Enrico were all at the University of Chicago after the war. And we used to play doubles on the tennis courts at the Faculty Club. And we used to play every Saturday. Enrico was one of the foursome and he would show up even though after the war he became very renowned in the country. He was on the General Advisory [Committee] in Washington, etc. He would be in Washington saying he has got to go home [because] he has an appointment. The appointment would be our tennis game.

He was an interesting man and I can’t say I was an intimate of his. His closest people in intimacy were people that he knew like Edward Teller, Hans Bethe, etc. some of his peers. He liked to spend a lot of his leisure hours with younger people. I think he liked to think of himself like Socrates.

Lewis: Tell me about what the other two members of the foursome were like.

Tabin: Herb [Herbert L.] Anderson. Herb was a very close and dear friend. He became head of the Nuclear Institute; [he was] Chairman of the Department for a period of time. In Chicago they have a rotating system. Other places the positions are more permanent, but Chicago here you are made a chairmen for three years or something, I am not sure exactly, then it rotates around. He is one of the senior members of the Syncro-Cyclotron in Chicago.

After the war he was a very interesting person and married a stewardess, airline stewardess, Jean, Jean Anderson. They had a number of children. They lived near the university in one of the houses where the faculty live. He was a little more serious, I think. He was certainly a wonderful friend. A very, very bright individual.

Darragh became one of my closest friends. He presently is retired. He was at the University of Chicago, went back to Los Alamos as Assistant Director of one of their very big projects. He is now retired. Lives in Santa Fe and we correspond occasionally. I was the best man at his wedding. His wife is still living, I think, but last I heard she was in a nursing home. We are all getting along to the tooth and things change. Darragh is a very quiet, understated individual. A very, very good friend.

Lewis: You talked about Enrico Fermi working hard during the day and then clearing his head of work at night.

Tabin: At the university that is what he did. Obviously, at Los Alamos it was a little bit different because he was director of a large number of groups. He was Technical Director of the program so he was more, I think, more administrative, more getting involved.

Lewis: I’m interested in your thoughts about creativity because one theory of creativity is that you think about a problem intensely and then you let it rest. And during that period ideas are germinating and then creative thoughts occur. Is there a pattern that you have noted in terms of some of the brilliant scientists that you have worked with or do many have different patterns?

Tabin: They may have had these patterns. If they are I wasn’t privy to the pattern. I couldn’t tell that they have now germinated an idea—that they are now thinking about the idea and they are now doing so and so.

My visible recognition of what they were doing is when they came out with something that nobody followed before. Something that was say new and unusual. You can do it in various ways. I know that I have some friend who is a geneticist who runs a big laboratory. He gets great excitement when he has accomplished and he has a result and he realizes that he now knows something that is true in this world that nobody else knows. It is something that has evolved. He recognizes the importance of it, the newness of it and he is the only one who has a grasp of the thing. Has some great excitement.

Lewis: So you are talking about curiosity?

Tabin: I don’t know. I think each individual must react in their own ways to these various things. I think really brilliant people like Niels Bohr, certainly Fermi, Hans Bethe, various people do very creative work. And I don’t know how these ideas originated with them whether it is by concentration. Some of them like Enrico do this in many fields. I am sure that if he got into a discussion with you on orthopedics, he suddenly would come up with some new ideas, new instrumentation, etc. There are certain creative geniuses that have that ability.

Lewis: When you think about your own problem solving, when you’re working on a problem, do you just keep working away until you come up with a solution or do you work on it for a while and let it rest? What is your method?

Tabin: I think both. If I have a problem legal or otherwise my mind thinks about it. Have you ever forgotten the name of somebody and if you concentrate you don’t get it? But all of a sudden you relax and start thinking about other things and suddenly it pops into your mind.

I’ve seen solutions to problems occur that way. I work at them and had a very difficult time getting a solution, etc. Finally I’ll lay it aside and all of a sudden in the middle of the night, I’ll come up with a path in which to go. Other times I won’t. You know, it’s not a sometimes you have a problem, you work at it and you try the various ideas and one of them clicks.

You know at least with myself, each way works but not for every solution. I think the creative mind comes up with much more ideas, is much more innovative. I don’t put myself in the category of some of these peers that I have worked with. Some of them are I find very exceptional.

There are exceptional people. They get born every once in a while and you have to cherish them when you find them. The interesting thing was that at Los Alamos basically all of the creative people in physics in the US— certainly those that were in the atomic area, nuclear area, cosmic ray area, including mathematicians such as Johnny von Neumann who did the pioneering work on computers—were all present at the same time. It was very unique in the history of science. I don’t think you can ever bring together that number of people of genius in one place working on a common thing and doing it in a camaraderie way and not in a fighting-for-turf, etc.

Lewis: You mentioned before that several of the people at Los Alamos were refugees and had a very powerful sense that it was important that we get this bomb first.

Tabin: Sure. Wigner, [Edward] Teller, Bethe, and we had the entire contingent from England came down there—Rudolph Peierls. The best of the best were there. I think we’re very fortunate, you know?

Most of these individuals were Germans. Most of them, a lot of them like Bethe and several others were Jews who had converted to Catholicism. I think the reason they converted was that they were secular Jews. At birth they were Jews, but they were not raised in any religious fashion. And the laws of the country at the time in Germany, you had to be a German to be at the university and you had to be Catholic. That was no problem for them. They converted. They became Catholic. But then when [Adolf] Hitler came in and he said if one of your grandparents was Jewish, you’re Jewish regardless.

There was a large group that left Europe, came to the United States and for a lot of these people before the war, the center of science was Germany. And the people who were the center of the atomic projects were to a great extent European and German, of Jewish extraction. Had Hitler not thrown them out I am not sure where the world would be today. We are fortunate.

Lewis: Is your sense that there was such an enormous esprit de corp? That there wasn’t any sort of turf battles or ego issues that everybody was pulling together and realized that this was a very significant project?

Tabin: Yes and no. Teller, for example, felt that he ought to be head of theoretical physics. And Hans Bethe was put the head of theoretical physics at the program. It took Oppie, Oppenheimer and [Norris] Bradbury and some others there to bring order to this and sense to the whole program. And to make sure that each one worked in a cooperative way.

I mean, I think that Oppenheimer did not contribute significantly to the technical aspects of the program. Well, I shouldn’t say that because I think he was very, very good in that if there was a meeting or there was a controversy to go this direction or this direction, he would be very influential in making the decision in which direction to go. But the different directions did not come from him. He was brilliant; he had an orderly mind. He was able to take the ideas and synthesize them, make reasonably good, excellent decisions. He made good decisions as to who should be in charge of what and was able to discuss that with the people. He was a very, very good administrator and I don’t know anybody who could have done the job as well.

Fortunately, I think, Groves saw this because as you probably know Oppie in his younger days spent time with various communist or communist controlled groups. His brother was a member of the communist party; his wife had been a member of the communist party; most of his friends were far leftish. Normally when you’re talking about a project like that, which we are talking about, you wouldn’t select such a person to be a person that you would make as a—not even as a head—but bring on board and provide him with the classified information necessary to confront a project. I think Groves recognized how important he was people wise and in handling people and running people and running meetings, etc. and brought him in in spite of that.

As Oppie grew older, like most of us, he became more and more conservative. He was never directly tied to the communist party, though he was quite wealthy and supported a lot of left wing organizations in his younger days. But they were smart enough to recognize his value.

As history has proven, as far as one is able to tell he is a very good, loyal citizen. I think before the ends of the war he was a committed anti-communist. He got involved in politics and was on various political organizations for the government and was making decisions for the government. It was a pity he was pilloried the way he was because he made magnificent contributions to the United States and its security. 

But his failure was that he refused to give up the names of all the people he knew who were associated. After the war it was the McCarthy era. All you had to do was get a rumor of somebody supporting a left wing organization and he was out of a job.

There was a group that wanted nuclear energy to be under international control. Make it not just something for the United States but for the world to have it buried so it is never used. Oppie thought that, Fermi thought that. Others did. I’m not sure I didn’t at the time.

Things changed when Russia got the bomb and it was on the way to developing the thermonuclear. Obviously, you don’t want somebody else to have it. The things went around and support for the thermonuclear became something that the people like Oppie and others decided had to be developed in the United States.

But you could go back to a period of time when people were arguing, is this a rational thing to do? Is this something good for the world, etc.? That doesn’t make them subversive, obviously, but that cycle took place. Now we are in a situation, which isn’t good. Nobody likes the idea of terrorists who if they get a hold of it—what will they do with it?

Lewis: You are really in a unique position because you have worked with the leading scientists of your era and you have two sons, one of whom is a leading scientist and the other is a leader in the field of medicine. Do you see parallels? Do you see differences? You have lived through many technological advances do you see advances in the way people approach problems? Do you think that we are evolving as far as human nature? Or do you think people are very similar now to how they were before?

Tabin: Well, I don’t think people change, but technology changes. Technology changes not by the masses, but by a limited number of brilliant people, that things are advancing very fast. We go through the nuclear area— I mentioned the video area that occurred that was the biotechnology revolution where you are doing genetic things that were impossible previously. The entire genetic code is available at almost affordable prices now and it is going to come down to the point where with a few thousand dollars they will be able to read your entire genetic code and be able to see if you are susceptible to certain diseases. It is going to change the entire field of medicine.

The computer era has come. Things that are available now we were just thinking about in those days. First computer was developed at Los Alamos. We were doing some of the calculations for some of the weaponry. They needed mathematics and to do arithmetic very fast. With ordinary means it would take them years to do and they developed a computer to do them quickly. In those days all we had was a Marchant calculator and some mechanical calculators with gears and wheels that operated very slowly.

I remember the first computer that was in a room several times the size of this room filled with vacuum tubes to make simple calculations on the computer. Now if you remember the first early hand computers to do arithmetic, that just did addition, division, etc. They cost $500 or something for a thing, which you can buy for $5.00 today.

The thing has moved extremely fast and it is still evolving you are now having nanotechnologies coming in. It is going to revolutionize the way things are done and I don’t’ know what is going to come in the future. I assume it will be as exciting as the last 100 years. A lot is being done, but these revolutions are done by scientists, people with intelligence, knowledge, etc. which should be fostered.

At the end of World War II we were, for a number of years, the leading country in education, science technology. Today I don’t know where we are, 23rd or something in the world. We are overtaken—the kids in Korea, Japan, various places in Asia—their education of youngsters coming out of high school is far superior to what we have in the United States. I think our educational system has to be strengthened, brought up to date. Money should be spent in that area. Forget about the military, etc. We are short changing ourselves in the long run. It is these young people today that is going to make the world tomorrow.

Lewis: Are you optimistic that we have the political will to be able to do that?

Tabin: I’m not sure. I hope we do. That’s all I can say. Certainly if you look at how we spend the money, where our budget has gone, you look at the Obama regime, which is supposed to bring the bright future. He is not spending the effort and the money to change things at the fundamental level of education. We are not bringing through youngsters that will have the ability to change the world the way it should be.

Not saying that there aren’t none, but you go to any place—go to Harvard Medical School today you’ll find that you’re better than I am at giving the numbers, but I think at least half of them are Asian or European, not American. Harvard medical is trying to bring the best people here. You take a look at the class, you don’t see an American class.

Lewis: When you look at your life experience what are some of your personal peak moments? What were some moments that brought you the most satisfaction, the most joy?

Tabin: I think you will find that anybody that has been at Los Alamos considers the years at Los Alamos, which is only roughly a two or three year period, as being the best years of their life. Best years in the sense of being in a community of peers on a daily basis. Having one big central part of the program and maybe 150 tops scientists. We all ate together in one place. You were together for breakfast, lunch and dinner. You had your separate group, which was a joy to be with. You will never get that again.

Lewis: Were there women scientists in the group?

Tabin: There were a few. Alvin [Graves], his wife [Elizabeth] who was a scientist. There was another one, Joan Hinton, she was in a subgroup. I worked with her with the first job I had when I went to Los Alamos was we built a small uranyl nitrate nuclear reactor and she was a part of the group. She was involved in building this reactor.

Now our group, which came in, our purpose was not to build a reactor, but to run experiments using that reactor to develop some basic knowledge that we needed, but the reactor wasn’t completed. Perce King was the head of that group building that reactor. We joined Perce King’s group—Herb Anderson and Darragh Nagle and myself—until that reactor was built. She was a member of that group, Joan Hinton.

She was a very, very brilliant young lady. She was actually an Olympic skier and unfortunately the war came along and we didn’t have the Olympics then. She was a very good outdoors person, skier, and a very good scientist. Her mother [Carmelita Hinton] started—what is it the Putney School?

Lewis: Putney School.

Tabin: Putney School up in Vermont and that area. She had a brother who was a communist and went over to China and with the Chinese communist group there. She used to go over there and she married a friend of her brothers who is also a communist, in China, and she has lived in China ever since. She died about a year ago.

For a long, long time she was on the subversive list because she had been on the program. But she, to my knowledge, when she went over to China, she changed fields completely. She spent her life over there helping to run a communal farm and in charge of modernizing and bringing modern equipment into China for farming. We saw her maybe fifteen years ago when she was already in her mid-sixties or so and I guess for the first time was allowed to come back to the United States for a visit. She advised us she had never been badgered or never got involved in science outside of agriculture out there.

There were a lot of people and a lot of women who were assistants. We had the SED, Special Engineering Detachment. A group of engineers that came that were used by the program for doing routine calculations, routine things. Los Alamos itself was an Army base. So they had not only an engineering detachment they had a detachment of WACs—secretaries who were out there.

Lewis: Tell me aside from Los Alamos, what were some personal highs?

Tabin: Personal highs were when the times of major discoveries being made by the clients’ breakthroughs in technology. Interesting things that occurred with my own children gave me great satisfaction, whether they won a tennis match or what have you. I don’t know. Some things happen that you don’t predict.

One summer Geoffrey [Tabin] wanted to come to San Diego because in San Diego they had the La Jolla Beach and Tennis Club where all the young tennis players from La Jolla used to practice and train. They could do that all year round.

So he asked me is there some way I can get him a job at the Salk Institute so he could spend time in La Jolla playing tennis there. So I brought him out to La Jolla. I asked one of the professors down at the Salk Institute, Roger Guilleman, would he mind having a gopher for the summer.

And Roger said, “Oh that’s great.” He said, “I was planning to have my daughter here and I was afraid everybody would say it is nepotism. It’s great to have your son here also.”

So Geoffrey spends the time in Roger Guillemin’s lab for the summer and somewhere along the summer, Roger wrote a paper and he was very much interested in having his daughter included in the paper. He couldn’t do it by himself. So he had Geoffrey and his daughter do some scuff work on the program. I don’t know what—he’ll have to tell you what it was. In writing the paper, he acknowledged the great help he received from his daughter and Geoffrey [Tabin] in running the experiment.

The following year Roger Guilleman got the Nobel Prize. What did he get it for? The work that was reported in this paper.

I get a personal high every time there is a gratifying achievement in the family whether it was from Johanna [Tabin], from Geoffrey [Tabin], from Clifford [Tabin]. You know, Clifford has won a number of prizes as has Geoffrey. They all give me great satisfaction as they occur. I think I’ve just lived a charmed life in that sense.

One doesn’t expect it. When Geoffrey and Clifford were small, if someone would ask me what they are going to be, what they are going to do, I couldn’t tell you. I just wanted them to live as I had, as I have done, a life full of joy. Not just joy in being able to go to the [Chicago] Bears game, but every minute of their life. I wanted their work to be a joy; I wanted their leisure to be a joy. I wanted them to be in something that they really liked. Money was not the answer. It was like Butan.

Lewis: Gross national happiness.

Tabin: Gross national happiness. I wanted them to be happy in whatever they wanted to be. If they wanted to be a performer, a jazz guitarist, I didn’t care. As long as they enjoyed what they did, enjoyed life to the fullest. I have been very blessed that that has occurred. I couldn’t have predicted where they would have gone. I know Clifford very early when he was young, wanted to emulate me in a way and go into physics and science. I thought maybe he is going to go into physics or mathematics. He ended up as a geneticist. A completely different field, but very successful.

Geoffrey, I didn’t know. In his younger days was a climber and tennis player, an outdoors person. I hadn’t the slightest inkling he would become a renowned ophthalmologist. Both have made their own way. I think they found their niche. I think they’re happy in what they do which makes me happy.

My wife was extremely successful. Nobody has mentioned her, but Johanna, God bless her soul, was a respected psychotherapist. When she started out psychologists were not psychotherapists, they were clinical psychologists doing testing. There wasn’t even training for a psychotherapist. She had to go over to England and studied with Anna Freud to get her training and became a respected member of her profession.

Lewis: Including receiving a lifetime achievement award from the American Psychological Association.

Tabin: Yeah. She has a wonderful circle of friends. She was highly respected. She enjoyed every minute of what she did and I think that it has been a blessing to be in this environment. I just wish that everybody had an opportunity for the same. At any rate, I am happy with the consequences of my radiation.

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