Per-Olov Löwdin

Löwdin:

I am Per Olov Löwdin.

Hoddeson:

We’re having an informal conversation on Sanibel Island. I’d like to know about the origin of the winter conferences on quantum chemistry and solid-state physics that have been going on now for about 15 years. Is that correct?

Löwdin:

Fifteen years, that’s correct.

Hoddeson:

Per, you are the director of the conferences. Were you so right from the beginning?

Löwdin:

— from the beginning, yes. They were my idea, and I started them in 1960, I should perhaps tell you that I am professor of quantum chemistry at Upsala University, Upsala, Sweden, and also graduate research professor of chemistry and physics at the University of Florida in Gainesville, Florida, and that these conferences are part of our international exchange project. I can tell you a little bit about my personal history and background, because the fate of a Swedish scientist is very peculiar. We have a very uncertain type of career. You go through the university. You get a doctor’s degree. And then you may become docent. And legally, you can have a paid position as a docent only for six years at the university, and then you have to go somewhere else. And if you have a family and certain responsibilities, it’s a terrible situation. Anyway, I took my doctor’s degree in ‘48. I got my first invitation from the United States in 1950, and I went to Hertha Sponer at Duke, Mullikan at Chicago and Slater at MIT. And I have spent about half of my time in this country since 1950, still trying to keep a foot in Sweden.

Löwdin:

What happened was that I had my six years, as a docent at Upsala University and then I was offered a professorship by MIT. So it was all set, I had accepted, and it went into the newspapers. And then I was called by a representative of the King of Sweden for an interview with his majesty, and what happened was that he asked if I wanted to stay in Sweden, and I said, “I want a job.” So I was offered a job in Sweden by the King in person: I got a little group with a secretary, and an assistant, and we started the Upsala quantum chemistry group. Then I realized that I still wanted to have my American contacts, and that we were fortunate —

Hoddeson:

When was that —?

Löwdin:

This was in 1955 when this agreement was worked out. So I got some form of a group and professorship back in Sweden, and then the Americans also wanted the contacts, so I was invited to put up a project somewhere in the United States.

Hoddeson:

By whom?

Löwdin:

Essentially by the National Science Foundation who would back it. And if we could work on Latin America, the Ford Foundation would back it too.

Hoddeson:

I see. Do you know who was involved with making the arrangements? Did they let you know that?

Löwdin:

They didn’t let me know too much. One of the main contacts was also at Wright Field, where Dr. Lloyd Wood was then director of research, and he was involved with this too. But it was rather informal in the beginning. There were several universities involved. There was Slater at MIT and there were people at other places. So I went on a trip, on a lecture trip, and by chance I came to Gainesville, Florida, which turned out to be a charming little city, and in the university there, there had been little done in quantum chemistry. They asked me right away whether I would be interested in having an exchange and I said that the chances would be very very slim. But then I called Slater at MIT, and I called Mullikan in Chicago, and they said, “Why not? If we want to retire in a few years, then we may be interested to come down to you.”

Löwdin:

So that was the start of the whole thing. So in ‘58, what happened was that during the meantime, we had built up American contracts and American research also in Europe, particularly in Sweden. In ‘58 we started the first formal negotiations for exchange with Florida. I was supposed to come in December, ‘59, and I brought my family, Karin and, we had four children together at that time, and we were looking both for a place to live in Gainesville for a convenient symposium place, since we had the idea of putting something up here in the form of an international symposium. The background for the whole thing comes from the fact that quantum mechanics had its golden years between 1926 and 1932. And many of these ideas which were published in Physical Review, Journal of Chemical Physics, and Zeitshrift für Physik had been forgotten. Simply had been forgotten! You see, science has to live. Even if the results are in the books, if people don’t know about the theorems, about the discoveries, they are just dead.

Hoddeson:

I was under the impression they were being taught in the universities.

Löwdin:

Yes, you think so. But what is happening is some form of degeneration phenomenon — it’s just like with the Beethoven symphonies. They were put in one specific form by the composer, but then the various directors make changes, here and there and so on, and after a few decades, you just don’t recognize the full spirit of the original work anymore. This is even more pronounced in the sciences.

Hoddeson:

I see, so you wanted to use the original works.

Löwdin:

— and not only that, we wanted to use the strict work which had been developed. And there was particularly one person by the name Harrison Shull who is now vice chancellor of the University of Indiana, but at that time was just a young professor, who looked into Zeitschrift für Physik for the papers by Hylleraas and found out that Hylleraas had discovered many many theorems which now were forgotten. You see, what is taught in the universities is a framework of the courses, and all the beautiful details which made the embroideries of the thing may be forgotten. They fade out. And he was horrified by this development, particularly looking at the fact that many government agencies were still paying for research to get these results which were already found.

Löwdin:

So the idea came up that we would start a summer school to pursue the old work, bring it up to date and try to preserve it, we had our first summer school, five weeks in the Swedish mountains, in Valadalen in 1958, with about 40 participants, and then ending up with a one week symposium.

Hoddeson:

Are there any records remaining from those early symposia?

Löwdin:

Yes, there are some records.

Hoddeson:

It would be very interesting to see what was actually discussed at those meetings.

Löwdin:

Yes, and I can tell you what happened. Robert S. Mullikan came and Linus Pauling came and a few of the other great leaders: Borje Bak, Kenneth Hedberg, Otto Bastiansen, all of those who are now leading personalities in their various universities. There was published only a mimeographed report known as Acta Valadalensia III. Valadalen was a famous sports resort. And of course, the participants being up there for about five weeks wanted to make some jokes, so they published two volumes of Acta Valadalensia known as No. I and No. II, which just contain jokes about science. It was a joke collection. So, when finally Acta Valadalensia III came, all the libraries wanted No. I and II, and they have of course, not been available. They just disappeared. I don’t, know why.

Hoddeson:

You don’t have any copies left? Anywhere?

Löwdin:

I and II, we just don’t know where they are.

Hoddeson:

That’s a pity!

Löwdin:

Yes. We might be able to trace some in Upsala.

Hoddeson:

Perhaps somebody still has a copy in his file cabinet.

Löwdin:

Yes, perhaps — the Library of Congress has never succeeded in getting them, so far as I know, but they have No. III. So this was the start of the whole thing, and the first thing we did when we came over to America was to look for a place to have a similar symposium far away from night clubs and city distractions. So I and my wife and the family traveled along the entire coastline of Florida. We went to Key Biscayne, we went down to Flamingo, Key West, up here, the west coast, and found Sanibel Island. We went with the bus ferry out to the Island and couldn’t go back, and we stayed overnight and said, “This is a marvelous place to have a conference.” So we asked the man who had the little hotel where we were staying, if we could have a conference there, and he said, “No, it’s too small, but down at Casa Ybel there is a chance. Of course, they have no lecture room, but you can go down there.” So we went down there, and they had a gift shop which could serve as a meeting room, so we made the decision that we would try to start winter schools down here, and also conferences. And that was the beginning. The first winter institute was organized in December, 1960, and was sponsored by the National Science Foundation. And it would be three weeks in Gainesville, where we would pursue the elements of quantum chemistry and solid state theory, and then we would continue with two weeks down here, and then ending up with an international symposium, taking the participants from scratch up to the current research level.

Hoddeson:

By this time, had the University in Gainesville built up its Physics Department?

Löwdin:

Both the Physics and Chemistry Departments were under strong development, but we had agreed that we would build the Quantum Theory Project from scratch. The obvious difficulty was that I was only here in Florida for half an academic year, with the idea of spending the other half getting things worked out in Sweden. First of all, I had become formally a professor of quantum mechanics in Upsala in 1960. Then I got the permission of the Swedish Minister of Education, Dr. Ragnar Edenman, to set up this exchange program, but on one condition: I would give my entire lecture load in Upsala, Sweden, for the entire year, and then I wouldn’t have to take a leave of absence, but I just could ask for permission to do my research over here. I thought that made sense. I had no idea of salaries and tax structures and so on, so it was a great adventure. And also for my "boys," because in Upsala we had a small group which consisted of about 15 young Swedes and 15 foreigners. All the foreigners were more or less visiting professors. The young Swedes were offered positions over here in Florida, and the university was smart enough to give me at the beginning four professorships on a loan basis from other fields, and I would have to return these when I got government contracts. Of course, it looked very promising that we would have government contracts and so on. But it took a very long time to get them. We finally got them. But the most important thing was that we got these National Science Foundation grants for starting the winter institute. I should tell that the boys who came along were a very selected group — first of all, Jean-Louis Calais who is now on the island and is still my associate director in Upsala. There was Jan Linderberg who’s now the head of a quantum chemistry department in Aarhus, Denmark. And there was Klaus Appel who is the chief of the System Programmers on the Upsala computer. And they were very smart. When I went away, they took over the administration of the whole thing, and they set up the entire winter institute, except for one thing: they had not counted on the peculiarities of the climate. We had a hurricane by the name of Donna. And Donna passed Sanibel Island, I think it must have been in October, ‘60, I don’t recall the details, and I have to look them up, I must admit. Anyway, Florida had a hurricane. Donna was one of the worst ones, and it destroyed a great deal on the island here, so we couldn’t get in contact with the people by telephone. There was absolutely no chance of having any contact here. So finally Calais went down and found the whole place asleep. Nothing worked — no plumbing, no electricity, no heating, no conference room, nothing. So he went on the alarm and called the owner, Mr. Howard Dayton. And he went down here and got the whole thing, so to say, back together to life. Then, our arrival here was absolutely fantastic, because the place was chaotic. The crew you see who was supposed to receive us knew nothing about scientists, conferences and so on. The owner quickly lured a new manager who knew something about people, and the whole thing then went remarkably smoothly. We could tell numerous stories about Casa Ybel, and it became very famous in the beginning, because almost everything happened. We had a man who tried to light his gas heater; it was Professor George Handler, now at Georgia. He lost practically all of the hair around his eyes. You know, people were trying to stay alive during the nights, in the cold weather, by various devices.

Hoddeson:

How cold was it?

Löwdin:

Oh, it was just freezing. We had ice on the ponds. And it was very cool in the lecture room — no, in the gift shop. We had a very strange lecture room, because most of them, you know, are rectangular, but this one was rectangular the wrong way. The blackboard was on the long side, and we in the audience were all sitting in one or two rows, more or less. If someone wanted to show slides, there were no curtains and we were standing there, in the windows, trying to dim the outside light. But anyway, we liked the whole thing, and we worked very very hard, and, in addition to what went on in the conference room, we got out a great deal just by personal contact on the beach. So we were encouraged to come back the next year again.

Hoddeson:

How were the themes of the conferences chose each year?

Löwdin:

We have had essentially quantum chemistry and solid state theory was our basic themes for the entire period. Then we added collision phenomena, because this is part of chemistry. Then we added quantum statistics. Very early we added quantum biology. That’s one of the most interesting features of the conference, because it was not planned, that way, but it came about from the fact that from Paris we had two very distinguished scientists coming by the name of Bernard and Alberte Pullman from the University of Paris and the French National Science Research Council. They had started the field of quantum biology back — I hate to say it, Alberte is a very charming young lady — in the early 1940’s; by now that’s almost 35 years ago. They had quite a success in looking at the problem of carcinogenesis of hydrocarbons. So they spoke about these things, and we decided to set aside some time then for quantum biology. First it was half a day, then a full day. And during the course of the series of symposia, this developed. So, two years back, we had our first separate symposium on quantum biology, then followed by another one this year, and probably another one coming up next year. So this is about the themes. Solid state theory has always been very strong, depending on my own personal interests of course. Dr. Slater didn’t come for the first symposium; he thought it was in a ridiculous place. He wrote a letter, and said, “Per if you arrange it in any place that I can reach in a decent way from Boston, I will come, but as long as you are in Sanibel I won’t come.” I don’t recall for sure if he came the next year, but in ‘63 we decided to have the conference in honor of the great pioneer Egit A. Hylleraas, and Slater came, and fortunately fell in love with the island. Then he came to Gainesville and the University of Florida before his retirement from MIT, which was somewhat of a surprise to the people in Cambridge, Massachusetts, and he had a commuting arrangement, as I have, spending the summers at MIT and winters in Florida. From then on Slater has been one of the main personalities of the symposium. He now has a house on Sanibel Island, as you know. Very peculiar, the influence of Sanibel on various people — on science and on their lives. Mullikan got a professorship in Tallahassee, Florida, and he has also been a regular guest at the meetings. I should tell you something more about the winter institutes. They were about five weeks: three weeks in Gainesville over the Christmas holidays and New Year’s, and then two weeks down here, with 44 lectures a week, totaling more than 220 lectures and they were essentially for, shall we say, young professors. In practice, the average level was about associate professor, I would say. We had many intense discussions and many lectures. They were the counterpart of previous similar events in Sweden mentioned before, where we had summer institutes of the same order of magnitudes; five weeks, 220 lectures and seminars. Lots of hard work. We were nicely supported by the U.S. National Science Foundation, both here in Florida and partly in Sweden. In Sweden we were also supported by the Office of Scientific Research (OSR) of the U.S. Air Force, which, like ONR, served as some form of international research council. The Department of Defense has done an enormously good job in that connection, and has created a good will for the United States, which in my opinion can hardly be beaten by any diplomatic or military actions. They have really done a fantastic amount for international science and for the positive image of the United States.

Löwdin:

So we were supported on both sides by the National Science Foundation. And then the Congress passed a law that NSF could not give grants of this type anymore to “advanced education.”

Hoddeson:

When was this?

Löwdin:

I don’t recall the year, but it was quite a few years back. I would say it must have been around ‘67, ‘68. And then, everyone anticipated, of course, that the whole thing would break down. But then we inquired, with various people and agencies, whether we should go on, and we were told by the Department of Defense that they could not support the winter institute, but they could support the symposium. They were supported by OSR for a long series of years, and now ONR has taken over this responsibility. The winter institutes had to be financially self- supporting, and that was very difficult. Previously the National Science Foundation had asked us to charge a small fee. Now we had to increase this fee drastically to keep the institutes going.

Hoddeson:

Has that cut down on the number of people?

Löwdin:

Yes, it has. Because you see, the professors did this work voluntarily. They were mostly University of Florida staff, but we had also some people coming in from Israel, Dr. Ruben Phoncz, and we had Calais coming in from Sweden, to teach. And when it became financially more difficult, they gave up the idea of coming, because they couldn’t pay the expenses out of their own pockets. But the other teachers just went on lecturing on their own, without any remuneration from the university or from the participants. We could decrease the fee again, and, the essential point was then for the students to pay their living for five weeks in Florida. And you know, to live for five weeks in Florida, even if you count on the fact that you can get it down to $15 a day, OK, — just multiply by 35 days, and you find that, including the travel it comes to seven or eight hundred dollars for each participant to pay themselves. So then we started giving the winter institutes each second year, and instead of having 100 people the number of participants finally went down to 30. So we stopped temporarily. We don’t know yet whether we’re going to have one next year. We haven’t decided yet, but it seems rather unlikely for financial reasons.

Löwdin:

Now the symposia have taken over. And the same group of people has been coming, year after year. We have people here who have been at practically every symposium. Sometimes they come as symposium leaders, which mean that they may give an invited lecture, 30 minutes or 40 minutes, or they may be chairman. If they speak one year, they usually don’t speak the next year. That’s a general rule, except for a few. And they’ve been very faithful. So the symposia are still going on. Then something happened concerning the proceedings, which I’d like to tell about. In 1963, we had the Hylleraas symposium and the proceedings were picked up by the American Institute of Physics, published by the American Physical Society in Reviews Of Modern Physics, in a beautiful printing and a big issue, so we were all very pleased, including Professor Hylleraas and particularly the Norwegian government, which had not previously realized that they had one of the great pioneers in their midst. So after that Hylleraas was given a very distinguished professorship and could devote most of his time to research. In ‘65, the American Institute of Physics again picked up the tab, published a separate volume of the Journal of Chemical Physics in honor of Mullikan, since the ‘64 symposium was dedicated to Robert S. Mullikan. But by then it was completely clear that this was the last time it could happen. AIP just put an end to these dedicatory volumes, because all of the great pioneers became 65 and 70, and if this would be fair, everyone should have a dedicatory volume. But then the commercial publishers thought that perhaps they could do this without too much loss. So we were approached both by Academic Press and by Interscience (now a division of John Wiley and Sons). The result was that Academic Press started to publish yearly volumes which we call Advances In Quantum Chemistry, as well as some dedicatory volumes — they have published one devoted to Mullikan and one to Slater; and Interscience started publishing a new international journal called The International Journal Of Quantum Chemistry.

Hoddeson:

So that is how it began? I’ve enjoyed that journal.

Löwdin:

Thank you. Yes. Thank you very very much. It’s a very strange journal, from many points of view, and this was the origin of it. There were discussions over who was going to take it, and only Interscience under Erik Proskrauer was foresighted enough to realize that quantum chemistry was a rapidly developing field. It’s very strange journal, with respect to its organization, and perhaps I should tell you something about it since I’m the editor-in-chief. We have three honorary editors: Slater, Mullikan and Heitler, and then I had two associate editors, Jean-Louis Calais in Upsala and Yngve Ohm in Florida, so the editorial staff is split on two sides of the Atlantic. The editorial office for the publisher was in London, so we had all our correspondence with London. The funniest thing was that the journal was set up, composed in Belfast. Then one copy was printed and sent to New York for photocopying in the United States. It was printed in the United States, and then distributed, and came back over. It was a true international operation, and it still is. It has changed a little bit. The Proceedings are now set in Israel. Anyway, Interscience was willing to pick up the Proceedings as part of the journal, so when we had the next honorary symposium, dedicated to Slater, the proceedings came in the International Journal, and from then on we have had it there because we have been very pleased with the publisher. They’ve always had the Proceedings ready in November or December, so we always had the Proceedings to show to the people when they came to the next symposium. So that’s the story about that, and we have every year had about 800 pages of Proceedings and 1200 pages of the ordinary journal, so we publish about 2000 pages of IJQC every year. OK, let’s now turn to the honorary presidents. Do we still have tape left?

Hoddeson:

We’re getting toward the end. Why don’t I turn it over now, then I won’t have to interrupt you in the middle of a sentence.

Löwdin:

The background noise is the sea, which is the Gulf of Mexico.

Löwdin:

I was starting to mention the honorary presidents we have had of the symposia. They started with Hylleraas back in 1963. He was Norwegian, professor at the University of Oslo, and a very remarkable character. He was the first one who really tested the accuracy of modern quantum mechanics because he applied it to the helium atom. And he did his work in Göttingen by means of a big, enormous desk computer, and he made the first accurate calculations showing that quantum mechanics predicted the correct ground state and excited states of helium. That was back in 1928.

Hoddeson:

I didn’t realize computing was used that early.

Löwdin:

Oh yes, he was the one who introduced it. He was a pioneer in computation — yes. So he used this big noisy hand driven desk calculator for getting the results, and solved the first big secular equations. He was a marvelous pioneer, and it turned out that quantum mechanics was in agreement with experiment, which was very important, because it wasn’t tested otherwise. It was the first real test. And then his methods were taken over by James and Coolidge and applied to the hydrogen molecule, and it turned out that, even there, it worked. And these calculations are re-done almost every year and refined and improved, and we can still see the fine agreement obtained by the pioneers. Then, the next one we honored was Robert S. Mullikan, of the University of Chicago, for his pioneering work, particularly the introduction of the molecular orbitals, for which he won the Nobel Prize in chemistry, actually the same year. The interesting thing was the Mullikan had, on his own, got the feeling for the modern electronic computers, and in Chicago started work on this in the late forties and in the beginning of the fifties, and arranged the first conference on the subject at Shelter Island in ‘51. So when he came down here in ‘65, there were many computational experts and quantum chemists coming in, and then many people from IBM. And from then on, IBM had a steady interest in the symposia, not in a continuous way, but on a year to year basis. This is a onetime obligation for them every year; they have very generously given us financial support, and done it early so that we can prearrange the symposium on the basis of essentially the grant we have from IBM. They have really been marvelous to us.

Löwdin:

Then, in ‘67, we had another of the giants that was John C. Slater. And at that time, he had started getting marvelous results in solid state theory. The X-alpha method, which he had developed earlier, finally started producing fruits, so from then on, that has been one of his continuous interests.

Hoddeson:

When did he move down to Florida?

Löwdin:

We have to look it up, but it was probably around ‘65, something like that. Something remarkable happened here, just a couple of months before the Slater symposium. I told you about the gift shop we had had earlier. The owner, Mr. Dayton who was very friendly to us and wanted to make everything good, built a special lecture room, which was known as the Bahama Lounge, and it was something very cozy — marvelous acoustics, all out of wood, it was one of the finest lecture rooms in this world, because there was a marvelous contact between the podium speaker and the audience which was unbelievable. Then, we also had a restaurant, with many old waiters, one known as the Doc, and also one which had the name Heisenberg, because when you ordered you were very uncertain of what you would get after your order. He was very proud of the name of Heisenberg. The meals were absolutely hilarious. They were often good, and the chef was always good, but the service was shifting — sometimes very quick, sometimes so slow that you never knew what was going to happen. The stories about these old times are in the thousands and someday we have to collect them. There are many many funny things which happened. Then, just two months before the Slater symposium, the restaurant and the Bahama Lounge burnt down. So we were very uncertain of where to go, and we went out again and looked for other places to have it, and finally Mr. Dayton said, “There’s no problem, I’m going to get a pre-fabricated house and get it up.” At that, time Dr. Slater was thinking of his own building plans on the island and he went down here to look. And at Christmas time there was nothing on the ground at Casa Ybel except for a big block of concrete. And amazingly enough when the people arrived for the symposium, around New Year, there was a new building standing there,

Hoddeson:

Is that this place?

Löwdin:

Yes. The lecture room was one of the worst places you can think of for giving lectures. There was no contact between the speaker and the audience. Everything was very grim and bad. That was the reason why they gave it a very peculiar name — it is called Löwdin Hall. And then, the restaurant too was changed — the cozy old style was gone, and pretty soon the health representative of the county came and said that we couldn’t use it the way we did, so we started having sandwich luncheons and so on, which meant that everyone could grab a sandwich and then come out on the beach, in the sunshine. And we loved it so much that we never looked for the restaurant any more. Later Mr. Dayton helped us to improve the lecture room so is now quite acceptable. So anyway, the Slater symposium went very fine, I think 250 participants, and at this time, money was still abundant in the United States, so all those that were married brought their wives and children, and there were more than 600 people on the island.

Hoddeson:

Where did they put them?

Löwdin:

Oh, they were in all the motels from the southern tip to the northern end. Every bed was filled with “scientists and whether the motel owners liked scientists or not, they were there. The next meeting in ‘71 was in honor of J, H. Van Vleck at Harvard, the man who has done more for the theory of magnetic phenomena than anyone else, and —

Hoddeson:

— also for the education of scientists in ‘quantum mechanics.

Löwdin:

Oh yes, a fantastic man, from all points of view. That was a very fine meeting. I may have mixed up the years — we had Henry Eyring from Utah coming for the ‘69 symposium, honoring his great achievements in chemical kinetics. I have to check the years so we get them straight. And then we had Ed Condon. And it was a remarkable meeting.

Hoddeson:

A special meeting for Ed Condon?

Löwdin:

Yes, we had a special meeting for Ed Condon, and this one must have been in ‘73, two years ago. This was at a time when the Vietnam conflict, you know, still very burning. The question was whether we would have peace or not, and Ed Condon gave a remarkable speech in his reminiscences, because he had been a journalist, a newspaperman in his younger days and he had interviewed many of the veterans from the wars, the First World War and so on, and he hated the wars, and he hated particularly the Vietnam War. So he gave an ordinary lecture about his scientific life, and then he gave a lecture with his opinions about the present government. The audience was somewhat mixed, so the reactions were also somewhat mixed. As you know, Ed Condon was the one who was fired from the National Bureau of Standards essentially by Richard. Nixon during the Eisenhower period. So it was a very fire-full meeting. Condon of course was honored for his discovery of the tunnel effects, for his many contributions in various areas in applied physics, and also for the book, Condon and Shortley, written about atomic spectroscopy. But Condon says that the book is nothing but an elaboration of Slater’s theories, so he didn’t take it too seriously. Anyway, it was a marvelous meeting. Then this year ‘75 we had one for L. H. Thomas, of the Thomas-Fermi theory, the Thomas factor, and for his contributions to computational methods. He was one of the really faithful ones, coming to almost every meeting here at Sanibel. The conferences here are going on partly in the meeting room, partly on the beach. We have also sport activities and so on. We don’t discuss when we are playing soccer that’s taboo, or water polo, but people get to know each other. We do discuss down on the beach, and now, there are things named after Sanibel. For instance, in the theory of spin projected Slater determinants, the expansion coefficients are known as Sanibel coefficients, because part of the development came from here. You can look in many many papers. There is one by Harrison Shull about covalent and ionic bonding, where he says, “I would like to acknowledge that the inspiration for this paper comes from a post-midnight discussion at Sanibel Island,” — actually it was between 2 and 4 in the morning.

Löwdin:

So there are many many credit lines, not only in the papers that have been given here, but in the general literature, and you can come back year after year and find that problems that have been posed one year are solved the next year. The most remarkable one was the one concerning the dependence of the correlation energy on the gradient of the electron density, which was posed by Professor Slater. Keith Brueckner took it up, and next year he came back with a beautiful solution. So everyone was pleased and we can see the effect of it; sometimes the problems are stated in the lecture room, sometimes on the beach. So, for all of us, to come here is an enormously stimulating affair. You may ask why we organize it and it is because it is one of the driving forces from the point of view of myself and my co-workers. And the point is, of course, that it’s so enormously stimulating to meet all these scientists, to hear all this, that we really are willing to undertake the job, the practical, job of arranging the conferences. We have by now got a certain amount of experience, so we just divide the jobs among ourselves. You have seen the support unit — called the “gofers” — which consists of a post-doctor and six graduate students. They have their own special roles; which are very clear. They divide the jobs by lottery. They are not paid to come down to work for us, but they like to meet the scientists and they take care of most of the practical problems by now. Then we divide the jobs between ourselves so they are not so cumbersome. We feel we have so much inspiration from it that it’s still worthwhile.

Hoddeson:

How are the participants selected? I gather it’s by invitation.

Löwdin:

No. Actually it’s an open conference. Anyone can come here who has his doctor’s degree, and the graduate students may come if they have two good recommendation letters. There has been a very strange change in the arrangement of the conference over the last few years, and this is the following: Previously, we just sent out the invitations, the announcements, and almost everyone sent in the message “I’m ‘coming.” Then by December 1, when I came over to Florida, I looked over the list that was coming and we outlined a preliminary program. We called the lecturers by telephone by about December 5 and said, “Are you willing to give a talk?” So many said, “Yes.” We further selected the chairman and the panel members and by January 1st we had a final program; then when the participants came down here, they got a program in their hands that told them what to do. It was a completely impromptu thing. There was also a lot of time for free discussions. Then when the money got tight, everyone had to give a paper, to justify the fact that they were coming down. Further the island started getting filled up by people even in January. So we started requesting housing deposits and early registration, and that meant we could put out the program, which was partly done by computer around December 1st. It is now fully computerized. Everyone’s data are punched on a card, and then we have a computer program which takes care of all organizational details for the organizing committee. Usually we have a printed output of the conference program coming out around December 15, which we send out. You have seen the printed program here. So by now everything is done in advance. But everyone can come, with the limitations mentioned before.

Hoddeson:

Thank you.

Löwdin:

Thank you.

Hoddeson:

You mentioned that you could tell me something about the Nobel prizes in Sweden — something that is not confidential.

Löwdin:

I could tell you that we in Sweden have a natural interest in the history of science and that this is connected with the Nobel Prizes. The Nobel will contain such regulations that nothing of the materials can be released whatsoever, which is unusual in all types of history because even the diplomatic files are opened after a certain number of years. Recently we had to reconsider the problem, since someone wanted to study Roentgen. Now Roentgen’s prize was in 1902. And in 1972 the researcher was not permitted to have access to the files. After some discussions, the rules were changed. Now the rule is that you can get access to the Nobel files, I believe, after fifty years. But you cannot get access to them if anyone involved in this particular prize, who has been considered as a candidate, is still alive. But fifty years is a rather long time, so I think this would probably be a practical limitation. We have an interest in the history because we must know who made the original discovery. There are a couple of rules in this connection which are of importance. One is that four people can never be considered for a single prize, and secondly a candidate should be the one who made the original discovery and stood for it. This means that we have to go back, first of all, through all the written documents and then also try to get conference remarks and the other communications between the people who really came up with the idea. And sometimes the people have recorded it themselves, for instance Maria Goeppert Mayer says in her little letter to the editor of the Physical Review, which gave her a Nobel Prize, that I am grateful to Enrico Fermi for pointing out to me that spin-orbit coupling could be of importance in the nuclear shell-model. There are many remarks of this type that are never recorded in science and may have been of great importance. We are very much interested in them. The procedure itself for selecting the Nobel candidates is well known. By September 15, the Nobel Committee sends out a request to all previous Nobel Prize winners, to all professors in Scandinavia in the various fields, and to all Swedish academy members to come in with nominations. Then they ask the entire faculty of physics and of chemistry of certain universities to suggest candidates which are all confidential of course. We get a very large number of such nominations coming in with the deadline of January 31 next year. Then, of course, we make a summary of all suggestions, and usually we can immediately see if there has been some form of lobbying going on. In such a case there is usually a peak somewhere; someone is suddenly without any other nomination getting so and so many more suggestions than last year and you have to take these things into account. The summary of the outside nominations is highly valuable for the committee as a standing point. Then the collected work of the various candidates goes out for evaluation in Sweden among the Academy members or among the younger professors in the field in Sweden who often really know the field. Then confidential reports start coming in. We get then in May or June, and we use part of the summer to study them.

Hoddeson:

It must be a tremendous job.

Löwdin:

It is a pretty good job and a very interesting job, and one of the most interesting things is just historical aspect.

Hoddeson:

Yes, certainly.

Löwdin:

Because we have to know exactly who really made that discovery. And many of the popular beliefs that that person made the discovery happen often to be wrong. He is perhaps number 2, number 3, or number 4. And then some of the forerunners did not stand for their ideas. And then they are eliminated so it could be number 2 or number 3 who were the most important ones. Every committee has five members, I am one of the members of the physics committee, chemistry has five, and medicine has five. We work out these evaluations and then we turn over all of our work in summarized form to a section of the Academy of Sciences called “the class.” In my case, the class consists of all the professors of physics and the number is 15. That means that in the class, there is certainly a much broader background. Class members come with a great deal of criticism and suggestions. And then finally when the class has made its decision the matter is turned over to the Academy of Sciences with the recommendations of the class. At that time, about 80 people are voting on the candidates, and the final outcome might be changed. For this work, everyone who votes gets a little miniature of the Nobel medal; it is very nice. So this means that everyone is turning up to get it. It is in pure gold, and it is very beautiful and rather valuable (by now around $100) so everyone eligible comes. But what I wanted to emphasize in my talk with you were just these historical aspects.

Hoddeson:

That means that around now the materials from the mid-1920’s are becoming available.

Löwdin:

Yes, it could become available.

Hoddeson:

That would be an exciting thing for scholars... Thank you.