THE FIRST THING I'D LIKE TO TALK ABOUT WITH YOU IS BEFORE WWII IN EUROPE, THE ATMOSPHERE BOTH POLITICALLY AND IN THE REALM OF ATOMIC PHYSICS IN THE '30S. AND THE REASON I WANT TO DO THAT IS TO SET THE STAGE...FOR THE WAR AND THE ATMOSPHERE OF SECRECY IN ATOMIC PHYSICS.

Yes. I have a story to tell there. Yes. I'm not yet on the air, I guess...

WELL YOU ARE, BUT GO AHEAD...

I see...Because I don't hear anything. Anyway, Well, you see...let me start when I started to get into this field. That was actually 1928 when I began what one would call today a graduate study. And I went to Gottingen in Germany which was the center of, one of the centers, Copenhagen was another, of the development of quantum mechanics. And at that time it was really a from the scientific point of view, an extremely exciting time. I mean suddenly we began to understand the structure of atoms and the structure of matter which was completely unknown before. And the new theories, new ideas which are very different from the old ideas. It was a revolution in science. And so, that's very exciting for everybody. But let me add, you know, it was very esoteric. We did not think at all that this business will have any direct connection with politics or with humanity. Or with...with the life of humanity. It was a pure, let me say, philosophic interest. And to make this clearer, more obvious, I will tell you one thing. It was, I think, during my study in Gottingen, I went to my professor, Max Born who was my PhD leader and the main theory is in Gottingen. And I...I knew him personally. And I went to him and said to him, you know, I'm not sure. I was thinking of switching over to medicine. And he says, why? Well, because I think that physics is very interesting. I'm deeply interested in it, but you know, it has very little to do with men, with people, with humanity. With the fate of humankind. And he made, I must say, a very prophet... He gave me a very prophetic answer. He said, you don't know how important this is going to be for mankind. And that was at the time where you had no idea about nuclear sab...nuclear processes or... Well, he won of course. And I stayed in this field. But this is to tell you how...how the... about the impressions we had. We're also a small elite. Uh...as I...later on, you see, when I made my PhD, I went first to...for post doctorate to Heisenberg. At that time you were not paid for post doc, I had to go to my parents for money, to Heisenberg and then I got a little position with Schrodinger and then I got, finally, a Rockefeller fellowship on the basis of what little work I did at that time—which was at that time recognized as of some importance, and spent a year in Copenhagen. Which was really the center of this new development. And why do I tell you this? Because, we had regular conferences there every year. Pictures of these conferences are in my collection. And there were not more than well, at best, 40 people. You know if you go today to a conference on any field in physics, you...you get hundreds, even thousands of people...a thousand people. So it was a small, I would almost call it elitist group which was not understood maybe even by many of the physicists who did not follow the... the modern developments. So, it was really a very separate thing. Now...we were, I would say, in an ivory tower. Now I'm speaking now of the late '20s when I began and of the very early thirties. Now in the early '30s of course, certain events happened, namely Hitler became the dictator of Germany. And many, including myself, of Austrian or German origin, I myself am Austrian from Vienna. It was clear to us that we will have very great difficulties in...in life. And Bohr, especially at Bohr's institute we were discussing that so very much. And Bohr was wonderful in this respect. He found money, Danish, English, American money to support refugee, Jewish refugee scientists. And he had a whole list of famous people like Franck, James Franck, and uh… von Halban, and Otto Frisch and myself also, not so famous. But anyway... And then so, in other words, the ivory tower was broken. Simply because of the political developments. But still, the connection between the physics which we are doing and the world, especially the political world, was not known at all. However, slowly....other things came up. Namely it...pretty soon we found out and I'm sure Peierls will talk about this, that this new quantum mechanics stuff...

CHANGE OF FRAME HERE. I'M STOPPING YOU WHEN YOU SAY THAT I'M SURE PYLES WILL TALK ABOUT THIS...LET'S TRY TO PICK UP THE THOUGHT THERE. IF YOU CAN START BY DESCRIBING THE BOHR INSTITUTE IN THE EARLY '30s.

I was just wondering because there's the thought here that...began to develop. And then I come back to this. In...In these times, it became more and more, actually that new quantum mechanics, not that it has weapon applications, but that it has technological applications. It reformed chemistry. And new materials may be produced. So this side of practical applications were already nearer to us at that time. Now let me say a few words about life in Copenhagen, because that was really a fantastic time. In a way I came rather late into that circle because the real heroic golden years were the '20s from '25 to '30. And at that time, Copenhagen was really the center of the development of new ideas. And here, there's something else, Niels Bohr had an institute there, The Institute for Theoretical Physics. Made by American money, however, to some extent, mostly. And this was to my mind, the first international institute of science in general. Because there were Americans, Germans, French people, Italians, Russians and so... Japanese. All young people, not many, perhaps 20 at best, but one of the young, all young people really enthusiastic about this new field. And there was this kind of atmosphere there of young people full of enthusiasm were working on completely opening completely new horizons. There was a...sort of a non-conventional kind of atmosphere where people made jokes a lot. You know, it was a...and felt We are really great. I mean, we are in this. We are making new discoveries and we are ahead of everybody. This...and Bohr, himself, was of course, was leader of it, but some how he lived with us. He was one of us. And we were sort of one society together. That was one of the most romantic times of my life and certainly of the life of other people who were there.

IT WAS A VERY INTERNATIONAL COMMUNITY.

Completely international. It was really where I learned the international spirit of science which I was always, very near to my heart, my whole life. That science is international. Should not ever be national. And that was born for me at least, and for many of us, in Niels Bohr's institute. And it was always Niels Bohr's principle also.

BUT THAT CAME RATHER ABRUPTLY TO A HALT?

Well it came to a halt. Of course it came to a halt when the Nazis occupied well it...it went on. Indeed it became even more so when the refugees came. Because here the refugees came from Germany, from Austria, and also from Italy, you know where Mussolini. So, in some ways, this made it even more international. Uh…

YOU'RE SAYING WHEN THE REFUGEES CAME INTO COPENHAGEN?

Yes. Into Copenhagen. Refugee physicists.

TALK ABOUT THE RISE OF HITLER AND THE REFUGEES COMING INTO COPENHAGEN.

Well, as you all know, I mean, Hitler very soon 1934, began to clean out the universities of everybody who has even only one Jewish grandparent. And a good part of this kind of theoretical physics, I wouldn't say a majority but a good percentage were of Jewish origin, at least in this very mild form. And so Ger... Germany, and later on, Italy, lost one of their most important leaders of physics. And now, Niels Bohr, who had the ability of getting money for support invited many people... of those people to come to Copenhagen. And there was a...the strangest ...supports. We got, for example, I was paid by a beer factory, by Carlsberg. I always drink Carlsberg until now, because they paid my fellowship and others too. So...it was quite clear. You know, Austria became Na...Nazified later, but it was 1938, but it was quite clear for anybody that you couldn't get a job in Austria and it is only a question of time when Hitler will get into Austria. In Germany, of course, it was impossible to get a job or even to stay there. Or to finish one's study. So there was this stream, stream of very talented young people to the different countries. I would say Copenhagen was excellent in this respect. England was also very good in accepting those people. Uh...to the United States, first sluggishly, but later on of course, most of these people ended up in the United States. Indeed I was admiring Niels Bohr at that time, in the '30s. He was not only participating, leading and following all the scientific discussions which we had, at the same time he went around to get money for us. For every year he made a trip to England and to the United States, as he calls it, to sell his refugees. And this was the way I was sold to the University of Rochester in 1937...when I arrived here. So he and a lot of other people got jobs through Niels Bohr in American and British universities.

YOU MENTIONED THAT GERMANY AND ITALY BOTH LOST PROMINENT PHYSICISTS TO THE EMIGRATION. CAN YOU TELL ME MORE SPECIFICALLY ABOUT THAT?

Names? Yes, yes. Well, let's start with Germany. Uh...here is Hans Bethe...Uh...I'm always bad with names. I'm sorry. Uh, but there's a large a number who had prepared... Hans Bethe, James Franck, Max Born, Ewald who died recently, I've forgotten his first name now. And Otto Frisch, Lise Meitner, Enrico Fermi from Italy who is one of the greatest of all physicists. Uh Emilio Segre, from Italy. They all, full or partly Jewish background...

(REPEAT THE QUESTION TO MAKE USABLE)

It is quite clear that due to this Hitler cleansing action, the whole intellectual activity at the Universities, not only in physics, but in physics especially, was... suffered terribly. I mean, take a university like Gottingen, for example. Gottingen had the two leaders in physics: Max Born and James Franck were expelled. Indeed, Max Born was expelled right away. James Franck who had fought in the first World War. In the beginning there was a law that those who had the medal were not expelled. But Franck then left on his own and later on he would have been expelled anyway. So here is a case where really you sort of...the head was cut off of the physics activities in Gottingen. The two leaders. Other cases in Munich where Ewald had to leave and Hans Bethe, who I think at that time was in Munich. So almost every German university, Berlin...in Berlin of course, Einstein is the first example. Leo Szilard who was active in Berlin had to leave and certainly many other names. Again it was...the best ones were cut off and the scientific life later on in Germany suffered very much. Of course, one should not be unjust. Some people stayed... Some people are not Jewish I mean, like Heisenberg, and Weizsacker and Otto Hahn who was one of those who discovered the fission process were not Jewish and stayed there. But the loss was terrific. Fritz Haber, you know, the famous chemist who in the First World War, really started this chemical industry for Germany was of a lot of Jewish origin and had to leave.

PRIOR TO THAT, AT THE BOHR INSTITUTE, HEISENBERG HAD BEEN THERE?

Oh yeah. Heisenberg was one of those. You know, I would say, these people which I talk, this enthusiastic young crowd, they were not always steadily at Copenhagen, they would spend some time at Copenhagen and Heisenberg spent a lot of time, even a month and maybe even years at Copenhagen, but then he always went back to Germany and...and went and visited Copenhagen for scientific discussions.

WHAT ABOUT SOVIET PHYSISISTS BEING...

Yes. At that time, oh yes, there were quite a number of Soviet physicists at the institute in Copenhagen. And I will mention two very important ones: One is George Gamow who finally ended in the United States. He's dead by now. And Lev Landau who's quite an outstanding man. He's...He also died. Uh...but others too. These are not the only two. These are the two most, best known Soviet scientists. There were Chin... Japanese scientists Mishina and Fujiyoka and a number of them who worked with Bohr in Copenhagen. So that clearly emphasizes the international character. An Indian scientist, Bhabha, Homi Bhabha, who played an important role.

CAN WE TALK ABOUT THAT A LITTLE MORE STRESSING THE IDEA THAT HERE WERE A GROUP OF PEOPLE WHO A YEAR OR TWO LATER WOULD FIND THEMSELVES ON OPPOSITE SIDES OF THE FENCE.

Well, let me make sure, which many people forget today. Soviet Russia was on our side during the Second World War. An important fact. And therefore...you cannot speak about Landau having to change political fences. That is true for the German and Italian physicists. Now, Heisenberg or Fermi and Segre and others but again, you see...Some of them were of Jewish origin so pretty soon they had to leave their country and were anyway, politically from the beginning on our side. Now when Heisenberg and Weizsacker. Weizsacker also played an important role. I forgot, by the way, an important man...Kasimir, a Dutchman, who played an important role in Copenhagen. But coming back to the two Germans Heisenberg and Weizsacker, there were others too, but these were the two important ones. They of course, really came into this quandary. And especially-

See during the time, during the '30s, of course we talked a lot about politics in Copenhagen and by no means were people like Weizsacker or Heisenberg especially pro-Nazi. And the significance of the physics we did for a possible war, was not at all clear. Not known to us. I think the only man who really thought about this in some ways is Leo Szilard. Who unfortunately died. Uh...however he was not one of the Copenhagen crowd and so his ideas were unknown or not discussed. So in so far there was still a kind of a split between...here's our science which is terribly interesting. And Heisenberg and Weizsacker have a lot of interesting things to say. And on the other hand, here is Hitler Germany that is clearly threatening the world. And so it is. One was of course a little more careful or didn't like to speak with Heisenberg and Weizsacker too much. We spoke more with the others about Hitler. But still, we did speak with them and they certainly disapproved of those terrible things that...that we read in the newspapers. The real split came later. Now...Heisenberg, also Heisenberg and Weizsacker were not so much in Copenhagen in the later parts of the '30s. There was simply no room. Bohr had difficulties enough to pay and care for those refugee scientists. And therefore you didn't encourage those people to come. Uh...but not because of political reasons. Now then of course, when the real moment of change was '38, maybe late '38 or '39, when Hahn and Strassmann in Germany discovered the fission process. And indeed they didn't quite understand what it is. They said something strange happens with uranium and only then Lise Meitner and Otto... and Otto Frisch who were at that time already refugees and Lise Meitner in Sweden and Otto Frisch in Copenhagen which is not very far apart, Lisa Meitner in Stockholm. And they sat together and trying to understand the discovery of Hahn and Strassmann. And this is the great moment in history when they found out this is a real split of the atom and therefore must release an enormous ammount of energy. But still it wasn't clear whether this can be a chain reaction or not. But from then on the discussions already started. I was already here at this time and Bethe was here and most of the people were already emigra... immigrated into... to United States or England. And then, we were of course, right away aware of the possibilities that this may be a chain reaction. And therefore a possibility of a weapon. And of energy production and a weapon. And then, during the war — of course during even the beginning in '38 or '39 was the beginning of the war. Correspondence between America and Europe were very difficult. And then for some of the developments now, were separated. For example, Otto Frisch and...were went to England and together with Peierls developed...thought about these ideas and indeed went rather far in the thinking and the... designing as to developing ideas of how a weapon could be made. A fission weapon could be made in case there are enough neutrons coming out and so... Which was not sure at that time. Uh...

COULD YOU BACK UP AND TELL US THE CIRCUMSTANCES UNDER WHICH YOU CAME TO THE UNITED STATES AND THEN WHEN YOU HEARD ABOUT THE DISCOVERY AND LISE MEITNERS REPLICATION.

That's what I just wanted to come to. ...Yes.

HOW IT FIRST CAME TO BE REAL IN YOUR MIND THAT SUCH ENERGY COULD BE...

Well, I came, as I said, to the United States in the fall of '37 and to Rochester. But I was in close connection with the physicists in also of course mostly with my German refugee friends at Cornell, Hans Bethe and Eugene Wigner was in Princeton, and Fermi, who was at that time at Columbia. And so, ah, we knew about the new developments and discussed them among us. And ah, we were very soon also able to see that there is here a possibility of a weapon. I think we were a little behind Peierls and Frisch, but not really much. And we were, there were two things, first we were thinking.... Let me say another thing which is important. I, and most of the others, were enemy aliens when the War began. Of course, one must be careful, the War began only '41 for the United States. But already at '39, we German refugees were looked at with um, a certain amount of suspicion because of our German or Austrian passport. It sort of occurred to us to be extremely ridiculous. How could we — how could German Jews who have been thrown out by Hitler and their families who were left behind, killed by Hitler, how could they be spies for Hitler? But anyway, that's the way it is, was. And so we discussed these things mostly among us. And then, Leo Szilard played a very important role in bringing these people together in discussing the issue. And now comes this famous event that Leo Szilard, who was mostly concerned, because he was actually the first one way back who had the idea that this is a source of energy or even of explosion, he convinced Einstein in Princeton to write the famous letter to Roosevelt, which indeed had an effect. And well, I wouldn't go into details of the history, because I don't know it too much anyway. However, then, finally the, roughly in '41, the... or '40 perhaps, '40, I would say, the American government saw the seriousness of this and started an action. And this, by having a committee. Now this committee started out in a very strange way. These people, I do not mention names, mostly because my name memory is so bad. But these people were over secretive, and didn't let anyone of us refugees or so-called enemy aliens participate in it. Fermi, a little, because Fermi was so important and he did the decisive work about the number of neutrons. In spite of this we went on discussing it among us. And I remember very vividly, the end of '39, and at the beginning of '40, I think it was the winter of 1940, when we were together in Princeton, that is, Hans Bethe, or Eugene Wigner, Szilard and myself and Einstein, to talk about the danger, and especially one danger, the danger that people are publishing work on how many neutrons come out of fission and so on and this work might be used by the Germans. And particularly we were worried about work going on in France, which was at that time occupied by the, not yet by the way, it was early '40. The occupation of Paris is in April, 1940. I know that because my son was born at the day when the Germans marched into Paris. And the, ah, so we were very much afraid of one thing, that the groups around Joliot and Hellbaum who worked in Paris would publish things that may be of use for the Germans. And then, I say, I was a very close personal friend of Hellbaum who was the close collaborator of Joliot, and they asked me to send a telegram in my name to Hellbaum, say...essentially saying, don't publish these results. We are also not going to publish on this side. And it's dangerous. Unfortunately, this action did not have the effect we hoped for. The French were somewhat distrustful of us with a little justification because shortly before this telegram was sent, the group in Columbia did publish things which we would not have liked them to publish. So they...they, perhaps with some justification, perhaps not, said, it is too late, things are already in pub why should we not publish our work, other people publish our work. So this action was actually not... this action for secrecy was not very successful. Well, at the... Yeah?

LET ME BACK YOU UP A BIT. COULD YOU TALK AGAIN IN A FAIRLY SHORT STATEMENT ABOUT WHEN YOU FIRST HEARD OF THE HAHN AND STRASSMANN RESULTS? WHERE YOU WERE? HOW YOU HEARD ABOUT FISSION AND WHAT IT MEANT TO YOU?

No, that is, I can tell you very clearly because it was very dramatic. Let me first say the Hanson...the Hahn and Strassmann discovery was itself not yet so exciting because it was not clear what happened there. It was just strange. Ah, what was exciting was the Meitner-Frisch interpretation, correct interpretation of it. And that came over here through Niels Bohr. Niels Bohr visited the United States in 1939 and gave several talks at Columbia and Princeton and other places. Some of them I was present and I heard then from Niels Bohr directly that here is something. This is fission, and that is the source of energy. And then, of course, there was Bohr was extremely interested in it, scientifically and otherwise, and he did some work, some very fundamental work with Johnny Wheeler, ah, who is now at Texas. At that time Johnny was in Princeton where Bohr was. And this work actually made it quite clear that if there are enough neutrons developed this can be an explosive...an explosive, much, million times stronger than chemical explosives, and that you need the, you need a special isotope of uranium, uranium-235, which is only less than a percent of ordinary uranium. And then, many people... were working on some problem, how can we separate -'35 from -'38.

SO YOU FIRST HEARD ABOUT THE NOTION OF ATOMIC FISSION FROM BOHR?

Yes.

AND THEN, MAYBE YOU COULD SAY THAT AGAIN AND SAY HOW THE REALIZATION THAT THIS COULD BE USED TO MAKE A WEAPON CAME TO BE EXPRESSED?

Well, I don't...not remember the exact steps, but I know that ah, the, ah, announcement of Bohr, and I even don't know whether I really heard it first from Bohr or first from some rumors about Bohr's talks and then I went on trips to Columbia and to Princeton and then heard it from Bohr, I don't remember anymore. But certainly this revelation was ah, the thing, you know, which excited us all tremendously. And the only question, are there really more than one neutron coming out of fission, which was then later proved by Fermi and also by Joliot in Paris, and then it was clear to us that this is a potential weapon. So that...I would say this happened in 19... end of '39, beginning of '40. And then we ah, went into this action of preventing publication.

OK.

OK. Well perhaps the most exciting moment was when ah.... when I and my friends found out the explanation of the strange processes that were discovered in Germany. The explanation by Miss Meitner and Frisch, namely that there's a real fission and that the nucleus of uranium is falling apart with tremendous energy development.... Well, the great exciting moment in this development was when we found out about these ideas of Meitner and Frisch to explain these discoveries of, in Germany, that the uranium nucleus really splits with a tremendous development of energy. Now here is something great, I mean something which has not only physics but also technical and military significance. If a chain reaction really can develop, if enough neutrons are produced. Now this we found out by the fact that Niels Bohr brought it over, it wasn't yet published and ah, told us, ah, gave talks in New York and at Princeton. And I'm not quite sure how I found out. I think I was in some of these talks, and some of the people tell me about it. But then it was clear, here is a thing which may shake the world. And then, of course, we went together and found out how could it really work, how could one, you know, the first ideas one has on a...on the back of an envelope, how one can put such a thing together and so on and so on. And discussed this. But also were aware of the fact, by gosh, I mean that...the Germans know about this. What about Hitler and couldn't he also make the bomb? And then ah, this worried quite a lot of us. And then, now, this, the whole thing had two effects. ... Now, ah, because we were aware of the fact that there were excellent physicists in Germany like Heisenberg and Weizsacker, and we didn't quite know where they stood politically, and they could really... why shouldn't they be able to do this? So that increased our fear. So, and ah, so we tried many things. First we tried to make the government, the US government aware of the fact that this is really a great and important thing and second, we tried to stop publication, we didn't want to help those people. There were publications of papers, and ah, investigations, for example, how many neutrons come out, at Columbia University and in Paris. And ah, since I happened to know these people in Paris personally, in particular Hans von Halban who was a very close friend of ours, I ah, I was asked to send him a telegram. We all came together, Wigner, Szilard and myself and Einstein, ah, and so we planned to do that. And I sent a telegram, ah, stop publication, there is an obvious danger. The trouble is, it didn't work very well because some things were already published, and the people over in France had the idea that we are, ah, we didn't want the competition, which of course wasn't true. But anyway, it didn't help too much. But fortunately at the end it didn't matter, because as we all know the Germans didn't come very far anyway with the bomb. But at that time we were very nervous about it. Now then came from our...from our point of view, ah, this thing that we were enemy aliens, most of us, so that we had very difficulties in getting access to...to the developments. Indeed, when finally the US government in... in 1940, the beginning of '40, ah, later, the middle of '40, took this seriously and had a committee to develop the nuclear bomb, we were excluded because we were enemy aliens. Sort of silly. How could a Jewish refugee who was thrown out by Hitler's and whose family may have been killed in the concentration camps be ah, working for Hitler, but that's the way it was. And ah, so, what we did is, we didn't give up. We discussed it among us. We said, let's... let's see how we would do it. And indeed, we came, we could redo for example, what Peierls and Frisch did in England and we went even a little further to find out what is the minimum amount of uranium necessary. And then came this very important paper by Niels Bohr and Johnny Wheeler, who worked at that time in Princeton to find out, and they found out that what you actually need is an...a special isotope of uranium. You have to get out of the ordinary ur...uranium the so-called uranium-235, which is less than one percent. And this is a very difficult thing to do. And many ah, physicists worked on...worked on it, especially Urey, Harold Urey, the American physicist and Rudolf Peierls.

Of course, ah, coming in 1937 to America was for us a liberation, tremendous... liberation. It was clear to all of us that there will be a war and there's Hitler and persecution and especially racial persecution, and now you come to a country that is free where you are accepted as a... as a like, as an equal. And ah, but then ah, when in '39, it already began, it became worse in '41 when America went into the war, there was a discrimination against the refugees from Germany. We were considered as enemy aliens. Indeed we were not even allowed to have a shortwave radio. And ah, at the same time we were officially not allowed to work on the nuclear problem, although we knew from...ah, we knew from all what we heard and discussed that this is going to be a decisive problem for the war, but we were excluded. So here is this irony that we who are probably more anti-Hitler than the average American, are not allowed to work ah, at this because we happen to have, most of us, happen to still have ah, German or Austrian passports. But anyhow we did work. And ah, we—

LET ME JUST GO BACK. "ANYHOW.." GO AHEAD.

Anyhow, we did work on it. And ah, we ah, we tried to do little calculations here and there. Some of us tried to solve the problem of separating the uranium-235 or...or to find other elements, like plutonium. But we were sort of-- we felt excluded from it, and we didn't like it very much.

DO YOU THINK THAT THERE WAS TIME LOST IN DEVELOPING THE BOMB IN THIS COUNTRY BECAUSE THE EMIGRES WEREN'T INCLUDED AT THE BEGINNING?

It may be. Ah, ah, it is hard to tell. Ah, I mean these are one of those iffy questions. But I do think, and that would be about half a year or so, if not more, time lost. I think there was time lost. It is not because we are more intelligent than the others, but because we had been in this field more than the others. And ah, that ah, that is the main reason. Ah, it is very hard to say.

COULD YOU RESTATE THAT AND SAY SOMETHING LIKE, BECAUSE WE HAD BEEN IN THIS FIELD IN EUROPE FOR SO LONG, HAD WE BEEN INCLUDED IN THE PROJECT FROM THE BEGINNING IT WOULD HAVE...

Yeah. It is not because ah, we are more intelligent than the other who worked on it, but because we had been in the same field, we had the experience in Europe. Most of us worked in nuclear physics for a long time, and ah, so we worked into, we were already into it. And after all, I think it would have made a difference. How much is very hard to say. Now a great change came then in um, beginning of '42 when especially due to the pressure of E.O. Lawrence, the Berkeley man, the inventor of the cyclotron, he saw the situation. And he was, of course, admitted to all this, ah, and also in the uranium commission, and he saw that this is ah, sort of the wrong way to do it. And he persuaded the government to reorganize the whole thing. And then, then came in General Groves, the famous General Groves, who actually also was the leader of building the Pentagon, I mean the building. And he was given then the task of organizing the ah, the nuclear bomb development. And I... I say I have very lot... I have a lot of criticisms against General Groves, but I must give him one credit, that he really saw through all these enemy alien things, and also that he selected ah, J. Robert Oppenheimer as the leader of the...the development. Oppenheimer as we all know had a sort of a leftist past, and ah, one would imagine that a...a general like Groves of military education would have been extremely suspicious. And I must hand it to him that he saw this is the man! I give him an enormous credit, although then I have many other objections against the way he ran the place. But that was his main very important positive contribution. So, Oppenheimer then, in spite of what the FBI has found about his past, as we all know he was actually, he was connected with the commm...with the communist movement. I'm not sure whether he was party member, I don't think so, but he was closely connected. I may, if you want, add here a... I think an important personal element. Ah, I knew Oppenheimer very closely already from Europe. And when we came here, Oppenheimer invited me and also my friend Plachek to visit him in his summer house which is very near Los Alamos. It is sort of a... a ranch which he owned there. And we came, we had been in Soviet Russia, I was in Soviet Russia a short time before I came here. And saw a lot of terrible things there, which I would not go into detail here. It was quite clear to me and Pachek, who was with me in Soviet Russia, that this is a really oppressive system. And ah, we talked about this to Oppenheimer. Oppenheimer and...let me say one thing, I do believe that Pachek and I, at... at that time in summer '38, had an important role in getting Oppenheimer away from communism. I believe so. He said so to me. Now anyway, coming back, in 1942, then, General Groves gave Oppenheimer the intellectual leadership of the project. And in the summer of 1942 he collected quite a number of people ah, and also ah, enemy aliens to come to Berkeley and to discuss the whole thing from the beginning. I have not been there at that time, there... I... I really don't know why. I perhaps should have been. But I don't know, maybe some reasons I... I cannot tell. Anyway I was not at this summer meeting. Ah, but... but most of the others were. And at that time there Serber's famous primer of the nuclear bomb was conceived and written. And I was then, pretty soon afterwards, drawn into. And I remember very well that was the end of '42, beginning of '43, when Oppenheimer asked me to see him, and said would you like to come... to... to a secret laboratory near Santa Fe for a purpose which you know very well I'm sure. And I said, "Of course." And ah...

COULD WE BACK UP A SECOND. TELL ME AGAIN WHEN AND HOW OPPENHEIMER APPROACHED YOU TO COME TO LOS ALAMOS.

Yeah, ah, I wish I knew the date exactly. It was I believe the end of '42 or the beginning of '43 after that summer session, about which I knew a lot, because Bethe told me, I actually saw the primer and so… And ah, I was expecting it so to speak in a way. And I was of course thinking very much of it, talking to my wife, ah, should we go, should we go to such a thing? Ah, where science in a way is really applied for killing people? But it was quite clear to me, and I...for... many young people don't understand it today. That if, in the midst of a war, which did not go well for the west at that time, ah, and with Hitler being perhaps able to make such a bomb, that I simply clear that you have to work with them. That is, for me at that time, although we discussed the problem with my wife and my friends, there was no question. Yes, we have to go. And so... ah, so ah, we did. And at this time the security system due to growth probably was really very easy. It turned out that any...any enemy alien who has two cleared Americans who vouch for him could be accepted. Now Oppenheimer vouched for me and Bacher whom you... you know, what's his name, Bob Bacher vouched for me, and in I was, and so others too.

LET ME STOP YOU FOR A SECOND. COULD YOU SAY AGAIN HOW YOU...YOU HAD DISCUSSED WITH YOUR WIFE WHETHER OR NOT YOU SHOULD WORK ON A PROJECT THAT WAS AIMED FOR... MASS KILLING. AND YOU DECIDED TO DO IT BECAUSE OF THE URGENCY OF THE WARTIME SITUATION. COULD YOU SAY THAT AGAIN?

Yes. Well, I would say it, evidently there was a problem for us, that here... this is a typical case where ah, our great science is used for war purposes, perhaps mass killings. Should one participate in such a thing? But it was quite clear to us that the answer is yes. First of all we were in the midst of a war which did not go well for the west at that time. Hitler made big strides in Europe. Ah, and at the same time there was this clear and present danger, if Hitler had this bomb and we don't have it he would use it and destroy the west. So the decision was quite clear for us, but we... it was for us a problem, a problem to discuss. There's another element which of course one has also to say, here was a relatively young newly arrived American, or not yet even American citizen, how could I not follow the...the request of helping this country in the war. So we decided clearly, it was clear for us that we should do it, and so we did.

GOOD. COULD YOU SAY AGAIN ABOUT HOW...TELL ME ABOUT WHEN YOU FIRST CAME TO LOS ALAMOS, YOUR IMPRESSIONS OF THE PLACE.

Well, yeah, that was of course a most romantic idea. Ah, first of all, ah…

COULD YOU START AGAIN PLEASE? I THINK I WAS STILL TALKING.

I see. Well, it was a very romantic episode. First of all, I remember this very vividly that I was told by Oppenheimer, by gosh, you don't tell anybody about the place and of course not the purpose. And I... I remember I came home, I came to my office and I hear loudly through the halls saying, "Professor Weisskopf, a call from Santa Fe, Professor Weisskopf, a call from Santa Fe," and I was told not to use the word Santa Fe. And so I took up the telephone and it was actually some detail when I should come or something like that. Another little episode is that we were told that our wives must feign ignorance, complete ignorance about the thing. And when I then went to Santa Fe to a conference, ah, immediately after I was called, actually the telephone call asked me to come there for a...ah, for talking about it, my wife was alone in Rochester, and...an FBI agent or a… I don't know, a secret agent came to her and asked her, where is your husband? And she says, she doesn't know where. He said, of course you would know. He pressed her very hard and she resisted and passed the examination. I think he put an A probably on the slip. Ah, of course she knew exactly what it was and where I was. OK, then I ah, we came there, I remember, we had at that time two small children, so my wife and the children stayed at Rochester. But I came to Santa Fe. We arrived there with the Santa Fe Railroad, a very romantic place, I... I didn't know New Mexico at that time. Very impressive. We went up to the mesa on a... on a dirt road. It was almost dangerous at that time to drive up there. We were housed in a... well, it was a school before, a boy's school. We were housed in a... in...in a shack where we had to sleep on, outside actually in...on a terrace. And ah, but somehow we enjoyed the romantic aspect of it, and we discussed then the plans and so, and I was asked actually to stay there, and ah, the family couldn't come yet because the whole thing was actually one big mud hole of construction. They not... not only built the laboratories there but they also built the houses ah, for the...for the people who would stay there. And that was in, as far as I remember, in March. And the family, and within three months, the whole ah, not the whole, but at that time village of Los Alamos was constructed. And in four...in three months the houses for our families, the laboratories for the cyclotrons all was there. And my family came in June, ah, and ah, and we moved in into these very nice apartments. They were not great comfort, and...but pleasant with a wonderful view of over the mountain ranges. You know, this is really ah, country. I think Oppenheimer chose it because Oppenheimer had his ah, his ranch there, quite near in Pecos Valley. And ah, so he loved this landscape and I did understand. We all understood why he loved that landscape. And then...

THERE WAS A GREAT FEELING OF COMARADERIE AND ENTHUSIASM. WHAT WAS IT LIKE?

Yeah, it was ah, very interesting. I mean of course this place grew the longer, I mean more and more we saw we would need physicists, hydrodynamic experts, we need experts of explosives and god knows what. First we were only nuclear physicists there and there was a relatively small group. And then more people came, more houses were built. And I have sort of the feeling, very strongly that this group were like the Mayflower, you know. We consider ourselves, we are the pioneers. I mean all the late...the late-comers they have not got the status that we have, you know, of being the first people there. And ah, but of course, the thing grew then very much. And you were right, it was a... a very pleasant closely knit atmosphere. And international at that time only in the sense that those refugee scientists were not born Americans. Later on then when the ah, when the ah, French, first a British group and then a French group and the...and Italians came, ah, things became then really international. But I must say the...these foreigners were only a minority. I must tell an anecdote there. Ah, when the British delegation was supposed to come, ah, I was asked to go to the... the railroad station was about I don't know, forty miles or fifty miles away from Los Alamos. So I was asked to go there and receive them being an European. And I was sort of a little worried, I mean I had no idea who they were. We were not told. This was sort of a secret. And I said well, I...I haven't got a British accent, you know. Now to my great astonishment who comes out of the Santa Fe Express? Rudolf Peierls, ah, Simon, Professor Simon and Bratcher, all three refugees. With just as thick a German accent as I have myself. And ah, but ah, then also, real Britishers came later on. For example, what's his name? Ah, I don't know. You'll have to fill it in.

YOU TOLD ME WHEN WE TALKED ONCE BEFORE ABOUT... THE FEELING THAT THIS WAS A TRULY AMERICAN EXPERIENCE FOR YOU, AND THAT YOU WERE ACTUALLY THE MAYOR OF LOS ALAMOS FOR A TIME.

Well, ah, we felt of course, right away at home. As I... as I said, we were the Mayflower. But quite apart from this we knew most of the people from previous acquaintances from scientific conferences, and so there was a closely-knit society. And now, as about...I think it must have been a half a year or maybe even a year after the beginning there were of course a lot of problems to be solved. The...the place was...we were civilians, we were not made military. Ah, and that was a condition that Oppenheimer and Bacher put on and I think very important, it was a very important one, so that we have the freedom of communication among ourselves. And then ah, there were of course problems of housing and problems of schools and so... And then it was decided to have a town council that will take the ah, the negotiations with the um, with the military authorities about all these problems. And ah, and the town council had to be, ah, there was an election for the chairman and for the members of the town council. It was a strange election because I remember that all of the candidates were nominated by others and the candidates didn't ah, didn't work for themselves. On the contrary they tried to convince people to elect the other one . And ah, now I had seemingly very good friends and the effect was that I was elected ah, Chairman of the Town Council. Now you must imagine what that means for a recent ah...refugee, émigré to this country. At that time I think I was already citizen, because I got my American, my wife and I got our American citizenship in '43, that was just five years or six years after we came in. Actually we got it in Albuquerque when we were in Los Alamos. So I was already American citizen. But to be here this country six years and then elected by...by after all mostly Americans there, for having this position of confidence, of course was a tremendous impression on...on me. I mean it made me a real American. You know, and I must say I would probably been...been that also without it, but it really, I was sort of happy and proud about this.

OK, well it is interesting that some of us including myself, all due through the develop in Los Alamos, sort of hoped maybe we find something why it can't be done, why a bomb cannot be made. And there were lots of possibilities, you know, things turned out to be much harder than, as everything in...is always much harder than you think at the beginning. There's too much neutron absorption here and there is, that may not work and this may not work, and somehow I felt if we really can show that a nuclear bomb cannot be made the world would be better. I'm not sure that's true, but that's the way some of us felt at that time. I don't want to speak for everybody. And I felt that way. Ah, up to the end. Of course in the last months it was clear... Well, even, I tell you, in '45, the test explosion was in June '45. In February of '45 a... something turned out that could have prevented the bomb, but we could overcome it.

SAY THAT AGAIN, AND KEEP ON A TIGHT SHOT. START BACK MAYBE WITH JUST A SHORTER AND MORE CONCISE STATEMENT THAT SOME OF YOU HOPED THAT YOU'D DISCOVER THAT IT WASN'T...

Well, all...all during ah, the development in Los Alamos, some of us, including myself hoped that it won't be possible to make a bomb, a... a nuclear bomb. We thought the world may...may be safer that way. But we were wrong. It...it could be made. In spite of many difficulties that occurred during the work.

COULD YOU SAY THAT AGAIN.

You're just like Brian. Well, all during the work in Los Alamos, ah, some of us, including myself somehow hoped maybe a nuclear bomb cannot be made, that there are really difficulties that cannot be overcome. We thought the world would maybe a better world that way. But of course, it wasn't so. There were difficulties but all these difficulties we were able to overcome.

GOOD. THAT WAS...BETTER. PERHAPS YOU COULD TELL ME ABOUT NIELS BOHR AT LOS ALAMOS AND THE IDEAS THAT HE BROUGHT WITH HIM? THE OPPENHEIMER AND?

Well, we were very much surprised when we heard, and it must have been 1944, that Niels Bohr is going to come to us. This was announced to us. Now all of us who were close to Niels Bohr were just overjoyed. Now, as he was brought in on a...on a secret name. It was Nicolas Baker and his son, Aage Bohr, whom I also knew very well, was, what was his name? Jim. Jim Baker. And ah, so we always called him Uncle Nick, which fits very well. Ah, he came one day and somehow as usual, Bohr is such a magnetic personality, such an impressive person, that his presence really changed somehow the atmosphere, and in a way, ah, it gave us hope. He...because he has this thing that, the...the nuclear bomb is something terrible, but maybe just in the fact that it is so terrible it may show mankind other ways of history than up...than up to now. And he was... he hoped always, as many of us hope even today that this terrible nature of this weapon, that is a million times worse than other weapons that this may finally bring mankind to the idea that wars are ridiculous. And he presented this idea in a very clear way in his optimism. He always had this idea when you are before a very great serious problem, that's a good moment, because then you will find a new solution, a new way of thinking, in science as well as in politics. And that was this idea there. I should say that he also helped in ah, in...in the actual construction of the bomb. He had a few good ideas. But that was not his main point. His main point was this ah, inspiring influence that maybe we do not only work at that weapon for this war. Maybe...and to overcome the danger of Hitler. That maybe this is really going something that will improve the world. I'm not sure whether it is so, but that was our feeling at the time. And ah, he did of course, quite a lot. He was only part of the time in Los Alamos, maybe even less than half of the time he was in the States, because he went to Washington, he talked to Roosevelt and ah, Churchill, went to England, and other statesmen about just what to do. And his idea again, the international idea. His idea was the only way to prevent this bomb to be a catastrophe is after the war to go together with Soviet Russia, that it was clear also developed the bomb. And ah, to collaborate, or even if it has not yet developed the bomb to internationalize not only the bomb but also atomic energy. Because at that time of course we were very much aware of the fact that this can be used not only as a weapon, but also as a source of energy. And his idea was this should be internationalized. At the moment it is not internationalized it will, and he said that already at that time, it will lead to an arms race, to an ever-increasing arms race. Now unfortunately, he was not able to convince, in particular, Churchill. We were told that he convinced Roosevelt to some extent, but then Roosevelt when he saw, ah, Churchill in Quebec later on, he was convinced by Churchill that this, we should not internationalize, we should not tell it to the Russians, etc. Because see at that time we didn't know whether the Russians work on it or not. The fact that Klaus Fuchs, you know, the spy, ah, has told the Russians about it, we...we were unaware of. Indeed Klaus...Klaus Fuchs was a very popular ah, member of the crowd. And ah, he was very much liked. He was sort of externally a very pleasant person.

LET'S GO BACK A MINUTE AGAIN AND TRY TO SAY AGAIN A LITTLE MORE CONCISELY ABOUT WHAT BOHR'S MISSION WAS THAT HE FELT HIS MISSION WAS. IN ADDITION TO COMING TO LOS ALAMOS AND DOING SOME WORK ON THE BOMB HE FELT THAT THIS POTENTIAL CATASTROPHE COULD ALSO BE A TURNING POINT, COULD BE PUT TO SOME POSITIVE USE.

Maybe I'll start with this point in science because I... it seems to me that is really ah, having been collaborated... collaborator of Bohr for some time, I was very much aware of one side of Bohr's character. Whenever there is a great difficulty and there were great difficulties in physics when the new physics came up, he said, "A difficulty, when you think there is no solution, that's the best moment, because then you are forced to change your way of thinking, and then you will get a new way of doing it." And that was of course true in quantum mechanics. And this is the same aspect he brought in when he came to Los Alamos. We considered at that time our work mainly, we must make this weapon so that Hitler cannot have it before us, and that it will help to win the war. But with his arrival, he talked about it such that we saw some more behind it. He said, "The great difficulty is the terrible nature of this weapon, is perhaps," so he said, "the way of solving one of the fundamental problems of mankind, namely the continuous wars, the difficulties between the nations. Maybe when this terrible destructive weapon exists and people are aware of it, they will see that war is no solution. But," he said, "this can only be done if this new idea is not in the possession of one nation. For example of the United States. It must be internationalized. So the only way of making out of this terrible thing something positive, so says Bohr, would be when the war is over to internationalize the management and the development of atomic weapons and energy. Now this idea gave us some kind of hope. It...it...it showed that we are working not only on a weapon of destruction we may even work on something that may deliver mankind. Now he did much more than talking to us. He went to the different statesmen. He talked to Roosevelt and to Churchill and to many others. And ah, ah, he did not go very far, I...I am told that he was lucky that Roosevelt understood the idea. Roosevelt died very soon afterwards. And but that Churchill, even before Roosevelt died was able to convince Roosevelt that this is all nonsense. Churchill didn't believe a word of what Bohr said. There was a complete lack of contact between, unfortunately, between those two people. Eve...Churchill even accused him of being a Russian spy.

I'D LIKE TO ASK YOU TO SAY JUST ONCE MORE SO WE CAN USE IT IN EDITING, ABOUT HOW WHEN BOHR CAME TO LOS ALAMOS HE BROUGHT SOME LIGHT, YOU KNOW, SOME HOPE TO THIS...

Yeah, yeah, yeah. When Bohr came to Los Alamos, of course we... the old Bohr disciples were all delighted to see the great Bohr again here. But it was much more than that. He brought us new ideas as it is in the character of Bohr to look at a situation in a different light. And the new idea was that he thought, he was convinced at that time that this terrible weapon is not only a weapon of destruction and may help us to win the war and may help us to prevent Hitler if he has it from applying it. It is more than that. It may unite the world. It may make wars obsolete. But he said this can only be done if the nuclear energy would be internationally administered. And this, it was a new idea for most of us. And made us more enthusiastic. It broadened our outlook. We may even do something which is more than just making a weapon. Of...

GOOD.LET'S GO ON AND DISCUSS AND DESCRIBE SOME OF THE TESTS.

It was ah, May '45 or something like that when it was now clear we have a bomb. And of course we cannot just send that bomb to the battlefield. It has to be tested. And therefore the plan was to test this in the desert of New Mexico. The test was called the Trinity Test. I don't know why Oppenheimer has chosen this name. It was in the middle of a desert. I was very lucky that I was one of the few theorists that were admitted to be there, the theoretical physicists because I have made...I didn't make myself, but I was leader of a group that made the calculations, the detailed calculations how much neutrons are in that distance, and how many gamma rays and so on. Actually we determined always the distance at which it would not be — no longer dangerous to be. Of course we didn't know it exactly. And I...I remember that the… the physicists said they are going to construct an iron cage and put me exactly at that distance where I said the gamma rays are no longer dangerous. If they had done it I would be dead, because it turned out that we underestimated it. And ah, we of course had enough margin of safety and put all the people at larger distances. Now there were the test...the preparation of the test was quite a romantic affair. We lived under even more, much more...

[BACKGROUND TECHNICAL DISCUSSION]

Ah, the life down there in the desert was even ah, more ah, romantic I would say, than the life in Los Alamos. Very primitive conditions, 120 degrees. Ah, it was in the middle of the summer. Ah, very little water. There was just one water hole where we could swim a little. And ah, I had to... I had my little, I had a jeep to drive from one station to the other where the observation stations were made, some of them unmanned to measure the effect of the bomb. And ah, and I had to discuss with people how much the this and that intensity would be. And ah, my jeep had a big hole on the bottom because these were all second-hand things that we had in Los Alamos, the first hand cars went to the front. And whenever there was a hole...whenever there was a bump you know, the whole dust came into the -- it was a really rough life, but somehow we enjoyed it. And then came the great day, ah, on July 16th, I'm sorry, June 16th, 1945. It never rains...

LET'S PICK THAT UP AGAIN. ARE YOU TALKING ABOUT THE DAY OF THE TESTS? IT WAS JULY.

I'm sorry. You're absolutely right. Then comes the great day of the test on July 16th.

LET'S START AGAIN. NOW.

Then came the great day of the test on July 16th. It never rains there, but just on that day it was supposed to be tested at midnight, a little before midnight a rain came. Great excitement. We can't do it during the rain, the observing airplanes won't see, and won't be able to measure and so on. So it had to be postponed, Ah, the meteorologists told us in a few hours it will be over so we will make it in the early morning hours. Now, let me say there were three places where you could observe it. One at six miles, which was a bunker, where you couldn't be out in the open, where, Oppenheimer was there, and General Groves and others. There was one place at ten miles where we thought we could be in the open and look at it, of course with glasses. And then there was one at twenty miles for people, for the larger number of people who had less to do with the test. I had the choice to be in the bunker around ten miles. I chose the ten miles place because I wanted to have the direct view of it. Somehow I felt I would like the psychological effect of this when you see it directly. And ah, now the postponement had a very interesting effect. Ah, we had an intercom system of course, between all stations. A radio...a radio system. And we chose, they chose a wavelength, which happens to be very near to a wavelength of a local radio station. And that was no danger at that time because the...the radio station started sending music at 5:00 in the morning and the test was planned at midnight. But because of the rain, or 4:00 in the morning - because of the rain the music station started indeed at the same time. And then, we had, I had this tremendous experience which makes me shudder today. You know, when I heard, when the countdown, you know, 10-9-8 and in the background, da-da, da-da da da-dum ... ba, the Serenade of Tchaikovsky, whenever I hear this piece I mean it shh...it shocks me. And many people don't even remember this because they were so concentrated, but I happen to be ah, very tied to music. And for me that was ah, one of the most grotesque experiences of my life. And that, ah, the accompaniment of Tchaikovsky, it came to zero, and then came this terrific explosion. Now we knew the intensity at the place where we were, ten miles, was 20 midday suns. So we had, of course, dark glasses, but I did look at the mountains to see how mountains look at 20 midday suns, and that's quite something. But what I did not expect although it was in the calculations was the heat. You know, twenty midday suns are very hot. They're about as hot as a big fireplace at one or two feet distance. And ah, when I saw a flash and felt this tremendous heat in my face I said, "By gosh, what's happening?" And I was, almost I thought, did...did atmosphere explode after all? We were pretty sure it wouldn't happen. But and then of course a quarter of a second later I said, of course, I mean light is heat. But I was scared at the first moment of this heat. And then...

Where shall I start? Well.... When we saw at zero, the tremendous explosion which was twenty times brighter than the midday sun at the place where we stand, ah, I was of course, tremendously impressed by this. I even looked at the side, look how the mountains look under this illumination which was fantastic. But then, I was scared! Suddenly I felt a heat in my face, tremendous heat at that moment, about as you would be from a very strong fireplace. And at the first moment I was afraid. Did the atmosphere perhaps caught fire, or explode? We calculated this. We were absolutely sure that that could not happen. But at that moment I felt, by gosh, maybe we made a mistake. Until half a second later it comes to my mind, obviously twenty midday suns are hot. And that's what I felt. But it was quite...it was scary and impressive. Then pretty soon, of course, things became somewhat weaker. I mean the...the fireball expanded, the intensity fell down. And ah, it's ah famous hemisphere developed and then ah, became a full sphere and lifted majestically from the bottom with this famous tail of dust. And became from white, yellowish and orange, and then again a fantastic phenomenon. Here you see this yellowish sphere surrounded by a blue halo. Again, we knew that such a thing -- but again, I hadn't directly expected that, and that was the radioactivity, tremendous radioactivity of that cloud went into the atmosphere and the atmosphere fluoresced kind of in blue color. Ah, a thin blue halo around. And that reminded me strangely enough of a very famous medieval picture by Mattias Grunewald "The Ascension of Christ". And if you look at that picture, you would see that here Christ is in a yellow, big yellow sun, so to speak, surrounded with a blue halo. And this tremendous contrast between that deadly instrument and that medieval picture of the ascension of Jesus, struck me as again, as a tremen — as an impressive experience. And then slowly the fireball lifted, went up and up, greater and greater, darker and darker. We took the glasses off, you could see. And finally reached the so-called inversion layer, when it developed into a mushroom, into the famous mushroom. And then the sun got up and illuminated this mushroom. It was a sight which nobody ever can forget who has seen it.

OK, I'D LIKE TO ASK YOU NOW TO CHANGE THE TOPIC FOR A MINUTE. WHEN IT BECAME CLEAR TO THE PEOPLE IN LOS ALAMOS THAT THE GERMANS WERE NOT GOING TO HAVE A BOMB. WHEN THE WAR WAS ESSENTIALLY OVER IN GERMANY, WHAT WAS THE FEELING AND WHY DID THE PROJECT CONTINUE?

Yeah. The Germans, the Nazis were defeated in, if I'm not mistaken in April -- no, May. May '45, right. And that was of course great celebration. I remember all

LET'S START AGAIN SO WE DON'T HAVE THE HESITATION AT THE BEGINNING.

Yeah, ah...when the Nazis were defeated in May 193 — 1945, there was, of course, great celebration at Los Alamos and I remember how our kids went and with other kids went through the streets banging pots and so on, a great celebration. Finally Nazism has been wiped off the earth. Ah, now comes the interesting question. One of the reasons was for us to work in Los Alamos was to prevent Hitler from getting the bomb. But obviously he didn't have it. Should we go on working? Now I don't think that anybody ever thought about this at that time, and I would like to explain why. Why? This was two months before the bomb was finished. We were in the midst of a tremendous thing where we worked almost literally day and night. How could you at this moment stop? Second. We knew what happened in Japan. Thousands of... thousands of Americans were killed. There was the danger of an invasion where probably millions would have been killed and millions of Japanese also would be killed. Of course, nowadays many people say that Japan would not have been able to pursue the war. But that's what we thought at that time. So we felt this is the weapon which probably and did actually end the war in Japan. That's worth it. After all we even — I remember we discussed this that with these tremendous fire raids at that time, about 40,000 people were killed everyday. So if...if we used the bomb and even killed 100,000 people and the war is shortened or is stopped, we still would save lives. So there were many reasons of this kind. And other.... thing, people thought we should perhaps demonstrate the bomb before we used it actually over populated people intended for populated areas, and then it would really perhaps end the war without killing people. So we couldn't stop. There was one man I think, a Mr. Rotblat who left, and I'm not sure whether he left because of that, or because he was a Pole and he was looking for his family, whom for... unfortunately he could not find. Ah, he went back to Poland. So ah, we went on. And I don't think there was much, as far as I remember there wasn't much discussion. It was sort of clear. You are in the midst of a thing, you cannot suddenly stop it. Not even in the midst you are almost at the end of a development.

SO THERE WAS A STRONG MOTIVATION TO FINISH WHAT YOU HAD STARTED.

Absolutely, yes, yes.

MAYBE YOU COULD SAY THAT IN A LITTLE MORE CONCISE STATEMENT. THAT EVEN, YOU KNOW, ONCE THE GERMANS WERE DEFEATED AND THE ORIGINAL MOTIVATION FOR BUILDING THIS BOMB WAS NO LONGER VALID —

One of the original, yeah,

YEAH. WE WERE SO CLOSE...THERE WAS NO WAY WE WERE GOING TO STOP.

Yeah, very good. Well, when the Germans were defeated ah, one of the main reasons why we went to Los Alamos, to prevent Hitler from making the bomb, was no longer valid. But still we were almost at the end of our work. We worked for three years almost day and night. Ah, you cannot stop. You wouldn't stop. Apart from the fact that we thought correctly that this bomb will end a very, very bloody war against the Japanese, which is a good reason to go on, very few people, I would almost say, practically nobody thought of stopping at that time.

GOOD, OK. YOU MENTIONED A MOMENT AGO THE IDEA OF THE BOMB MIGHT HAVE BEEN USED AS A DEMONSTRATION. AND IN THE CHAPTER THAT YOU WROTE YOU TALKED ABOUT GENERAL GROVES' REACTION TO GROUND ZERO AT TRINITY. AND A GOOD REASON WHY THE DEMONSTRATION WOULD NOT HAVE WORKED

That's right.

MAYBE YOU COULD TELL.

Yeah, OK. Ah, under the influence of Niels Bohr, and perhaps also without Niels Bohr in ah, 1945, towards the end of the war we all discussed very much what...what will be the consequence of this weapon if it is really applied. How should it be applied? And ah, there were ah, people who thought it would be better first to demonstrate it over an uninhabited region and see whether this has any effect. This was mostly proposed at Chicago by James Franck and his group. In Los Alamos we were sort of kept away from this. There was very little ah, political discussion allowed. But it was discussed also. And ah, ah, well, I personally was very sympathetic to this idea. But I learned a lesson perhaps ah, at the test. At the end of the test about 18... I'm sorry, 18 hours after the test, we thought...

(TECHNICAL DISCUSSION)

Ah, we figured out that about 18 hours after the test it was safe enough to go to the place, to the actual place of the explosion for at least, for a quarter of an hour or so without getting too much radiation. So a group of us went, actually several groups went there, and ah, ah, I was told ah, that General Groves was not in the jeep in which I was. Ah, but I was told that when General Groves was brought there and looked at it, he said, "Is that all?" He probably thought there was, there would be a hole to the center of the earth. Actually what you saw was a a... sort of a mirror kind surface of the sand about 200 yards radius where the sand was molten and again solidified, which of course for anybody who thinks would see that is a fantastic thing. But this remark of Groves' "Is that all," makes me a little doubt whether the Japanese generals would really have been impressed by a test. One could use this argument.

TWO SECONDS. OK.

We figured out that ah, about 18 hours after the test it was possible to go there and stay to the center where the explosion took place and stay there for maybe 15 minutes or a half an hour without getting too much radiation. And then several parties went there to...to look at it. And I was in one of them, and when we drove there we saw, of course, nothing standing there. But what was so impressive was that about a circle of 400 yards diameter, sintered sand. That means that sand was molten by the explosion and was solidified again. It had sort of a kind of mirror-like surface, which should show everybody that how tremendous the heat must have been there. Now when General Groves saw this, I am told -- I wasn't in the same party — he said, "Is that all?" He probably expected something like a hole to the center of the earth or so. And this made me actually think a little would the idea of demonstrating it to the Japanese general really have been an effective way? Of course one could have tried it and then after if it is not effective to use the next bomb. But we didn't have so many bombs.

GOOD. OK, I THINK THAT MAKES THE POINT. NOW LET ME ASK YOU ABOUT THE REACTION IN LOS ALAMOS AFTER THE NEWS OF HIROSHIMA CAME BACK.

Yeah. Ah, yes. Well, I would say, after the test when I...we came back to Los Alamos, we sort of suddenly had this feeling, now I can sleep, you know. Now I can rest. We have done our job. And ah, what happens now of application and so is not our business, and it took then about three weeks until August 6th, the Hirosh...the bomb was dropped over Hiroshima, August 9th over Nagasaki. Our impression is difficult to describe. In some ways, especially when after a few days it was clear that the war was over, in some ways we said, well we did it. The war is over. The killing of Japanese and Americans has ended, and it's we who did it. And that gave us a great deal of satisfaction. At the same time we were thinking of these other problems, of Niels Bohr's ideas, at least most of us, some of us, and that showed that actually our work starts. Now we have really to tell the public the real significance of this tremendous weapons...ah, weapon. Now we gave a lot of talks. From then on the secret was out. And all kinds of organizations, civil organizations ah, in...in Santa Fe and Albuquerque invited us to give speeches, and I gave a number of speeches. And I remember I quoted ah, at one of...of most of the speeches at the end the famous line of John Donne, "No man is an island entire for thyself, and when the bell tolls it tolls for thee." That means that this is really a matter that concerns everybody. Not only the American nation or the Japanese nation, it concerns the whole world. And we were trying sort of to preach the gospel according to Niels Bohr. And ah, I'm not sure how far we succeeded. We were, in a way it was successfully. I mean we were very much acclaimed. But I think the great acclaim was not so much that. The great acclaim was that we have ended the war, and half of the population had their children over there, and their relatives over there and they are now finally saved. And I know that this element came always to us. We were...we were really given presents. We were thanked for the fact that it was we who ended the war.

JUST BACK UP AGAIN. WHEN YOU HEARD ABOUT NAGASAKI, LAST TIME WE TALKED TO YOU YOU SAID THAT YOU FELT NAGASAKI WAS A CRIME, THAT IT WASN'T NECESSARY.

Well, yes. In the first excitement and the exaltation of the war is ended and we did it, we did not think so much about what I would almost call a detail, you see. But later on, it came to...my mind, and to the minds of many others –

WHY DON'T WE START AGAIN.

I see. Yeah. At first after the end of the war, we were all immersed in this exaltation and celebration and we were the great heroes who did it. And we didn't think too much about what actually happened. But later on, after several months of course we went back to think about it. What was actually done. Now perhaps one could defend in some ways the bombing of Hiroshima, although I would have preferred a demonstration at least to try it out. But anyway, it did have the effect and it end...it ended the war. But why did we really bomb Nagasaki three days after? No government was...would have been able to make any kind of decision to end the war within three days, and especially not a government in turmoil as the Japanese government was at that time because of the first bomb. So why did we do this? There were some ah, reasons the meteorologists said the weather is going to be bad pretty soon and then we cannot right away bomb a second city. But these are act...to my mind very bad excuses. So it is my opinion, I don't know how strong I should express it. I believe that the bombing of Nagasaki was a mistake, and I could perhaps even make it stronger. One could perhaps call it a crime.

OK, PERFECT FOR THAT. WHEN THE WAR WAS OVER, YOU STARTED TO SAY THIS BEFORE, AT FIRST YOU THOUGHT THAT YOUR JOB WAS DONE BUT THEN YOU REALIZED THAT IN A WAY YOUR JOB WAS JUST BEGINNING. COULD YOU TELL US A LITTLE BIT ABOUT WHY YOU AND OTHER SCIENTISTS AT LOS ALAMOS FELT THE NEED TO INFORM THE PUBLIC OF WHAT WAS GOING ON?

Well, when the war was over, and the first exultation was over, many of us, and I can only talk about me and about my friends, felt that this is now a decisive moment in the history of humankind. Ah, this may be — end world wars. It may bring in a different relation between nations. And it is, therefore, our duty to speak about this, and to get these ideas to the public. First of all, to make it clear to the public the tremendous difference between an ordinary explosive and this. That this is really quite a new aspect of warfare. And that wasn't clear to many people. So we found to our duty, and that was actually the main point in many speeches, to tell them that is... this is quite a new dimension of warfare. And I often wish today that we have not —I don't regret that we have emphasized that, but we should have equally emphasized what follows from it you know. That we must get into bet — into different relations with nations which are even antagonistic to us, as Russia already began at that time. Let's be sure that Russia was not yet the great enemy that it is now. But still it was already visible. And the idea of making an...the bomb international or even further to restudy the whole concept of military conflicts under these conditions which would lead to major catastrophe. That was clear to us already at that time, that any real nuclear war would destroy civilization. We didn't know about nuclear winter and about the H-bomb, but still that was clear. And so we felt an absolute necessity to organize and to spread this knowledge. And this is why I was active and many others in the foundation of the Federation of American Scientists. First it was called the Federation of Atomic Scientists…

WERE THE SCIENTISTS AFRAID THAT NOW THAT THE BOMB WAS IN THE PUBLIC EYE IT WOULD NOT BE HANDLED PROPERLY BY THE GOVERNMENT? BY THE MILITARY?

Ah, well, um, when the war was over and we ah, we founded the Federation of Atomic Scientists, we ah, were worried about many things. We were worried that the public doesn't know enough how terrible this weapon is, and how different this weapon is from the conventional weapons. We also felt that many people including leading... ah, leading politicians thought that America will have that secret forever, and that other nations will never be able to construct another...a nuclear bomb. This was a widespread belief, indeed even General Groves says for example that the Soviets will need 20 years at least, they will. And it I was quite clear to us, and especially to those people like myself who have...who have been in Soviet Russia and knew the kind of physics they know and do that this is sort of ridiculous. That the one big secret is that it is possible. And the moment the Russians see a bomb is possible it will take them, we guessed at that time three to five years. Indeed, it was four years ah, before they could make it. And that was again, also one of the aims of the Federation in our speeches and writings to make that clear. It will never be a monopoly. We cannot sort of rest now assured we have the nuclear bomb therefore nothing can happen to this, to the plan, to the United States or to the planet. And ah, unfortunately we were right. And then of course, what is the possibility? What is the solution? The solution would be internationalization. Now that was at that time a rather not so unpopular idea. Indeed there was a...the...the...the Baruch Plan of the American government and the ah, what is called? The Lillienthal plan to do that, to go together with the Russians. And then there was even a United Nations Commission under the chairmanship of Kramers, who is one of the physicists, a Dutch physicist. And ah, what we underestimated at that time was two things. First the very strong nationalism after having won a war, which would have prevented, did indeed prevent the United States and England to go into such a international administration. What we also underestimated was Stalin. I mean, I and a few people who have seen it over there knew what kind of terrible guy Stalin was. But after all he was at that time our ally and he helped to ah, beat Hitler. So, ah, unfortunately the chances of success at that time were rather low. And ah, some of us were aware of it. But still we worked very hard on it. We hope that things will become better. Unfortunately, so far they did not. But I am still an optimist, and I think as time goes on we must come to the idea. A world war is impossible. This, I think, has finally penetrated public opinion. I think everybody knows today if you really had a war between Soviet Union and the United States, the world would be destroyed, and nuclear winter is only one part of it. The world would be destroyed. That's something which we tried to preach at that time. Finally, after forty years, I think it sank in. But the consequences, what follows from it has still not sank in.

WAS THERE SOME OPTIMISM RIGHT AFTER THE WAR THAT IF PEOPLE ACTED QUICKLY THERE COULD BE SOME KIND OF INTERNATIONAL CONTROL AND ORGANIZATION?

I certainly...certainly this too. Ah, there was a great deal of...of...of optimism, especially by ah, people like Lillienthal and Oppenheimer and us in the Federation. Maybe we can do it. We did not see the -- we saw the difficulties, but we underestimated them. And ah, we saw the lesson. I mean after time then came the H-bomb, and again a discussion started, "Now we have the H-bomb, the Russians will never be able to make the H-bomb." They did it, actually they did it better at the beginning, only a year later. And ah, maybe that is an occasion to go together with the Russians. And Oppenheimer actually proposed this and his punishment was the famous trial and his being thrown out of all politics.

I'M GOING TO STOP YOU BECAUSE THAT'S GETTING BEYOND THE SCOPE OF OUR PROGRAM.

That's getting beyond the scope of our program, yes.

WHAT WERE THE OBSTACLES IN LATE '45 AND IN 1946. WHY COULDN'T SOMETHING LIKE THE BARUCH PLAN HAVE WORKED?

Well, I repeat what I said before. Yeah. I would say the obstacles that this idea of an internationally...international management of nuclear power and weapons, why this doesn't --did not succeed although we hoped it would, I think the obstacles that we underestimated were several. One is the nationalism, nationalism on the west and in the east. That ah, America and England had this secret, the Russians did not yet have the bomb. There was still the hope that we can keep that superiority. The second is, we underestimated ah, Stalin. I would say that it's perhaps not such a different point. The nationalism on his side. He distrus... distrusted the west. He may even had some reasons for that. And ah, he would, I think Stalin was just a character that we would never go into a real negotiation. And I'm afraid that turned out to be true, not only for Stalin but for the successors. Maybe it will change now.

WHAT ABOUT THE BARUCH PLAN SPECIFICALLY. DID YOU...WERE YOU INVOLVED IN THAT? DID YOU KNOW ANY OF THE PEOPLE?

Oh yes. Oh yes. I was not personally in any commission there, but since I was ah, one of the leading members of the Federation of Nuc...of Atomic Scientists we were of course in close touch. The Baruch...see, they started with the Lillienthal plan which was made... which was essentially drawn by Liliaenthal and Oppenheimer. The Baruch Plan was a little less ah, positive. A little ah, a little less ah acceptable to the Russians. And now I would not say by this, by a long shot that the Russians would have accepted the Lilienthal-Oppenheimer Plan. But it was watered down. Ah, because of all these reasons, nationalism and belief that we are actually so far ahead and so on. But I just, in hindsight I would say, the chances were very low that it could have been accepted at this place, unfortunate --at that time, unfortunately.

OK, WAS THERE— IT SEEMS LIKE THERE WAS LITTLE REASON TO BELIEVE THAT A COUNTRY WHO DIDN'T HAVE THE BOMB YET, YOU KNOW, WOULD ACCEPT...

Yes. Yes. That is one thing, although one could have said five years later, perhaps they could. But certainly that was in a... you are absolutely right. That was an important reason. You cannot, the world has been changed. I would say in August 1945, because before only very few people knew about the bomb. How can you expect that the...the world changes its thinking that fast. That just doesn't happen. As Einstein said, you know, the nuclear bomb has changed the world, but it has not changed our thinking. That goes slow. We can only hope, and I do hope it fervently that our change of thinking will be soon enough before the catastrophe occurs.

MAYBE...I WOULD LIKE YOU TO SAY THAT AGAIN STARTING WITH WHAT EINSTEIN SAID.

It was too much to expect that shortly after the end of the war, we could really get to an international agreement, so to speak, to an abolishment of war. It was just not time enough for the world to get accustomed to this new idea. Nobody knew about the nuclear bomb except a few of us. And here August 6th, 1945, the world changed. The whole idea of warfare changed, and it takes more than a few years for the world to understand it. As Einstein said, "The whole world was changed by the nuclear bomb, except our way of thinking." And we can only hope that this process of a new way of thinking will develop and will develop fast enough before there will be a nuclear world war, which will destroy everything we know.

I'M GOING TO ASK YOU ONE MORE SORT OF GENERAL QUESTION. IS THERE ANY...WHAT'S BEEN THE MOST SURPRISING THING TO YOU IN THE LAST FORTY YEARS VIS-A-VIS THE BOMB AND THE WORLD SITUATION? IS THERE ANYTHING THAT YOU EXPECTED THAT DID NOT HAPPEN OR?

Yes, ah, strangely enough, I would say –

START ONE MORE TIME.

Oh, I'm sorry. Yes. Shall I repeat your question?

NO.

Yes. The ah, if somebody had asked me in 1946 or so, in view of the fact that all these say, attempts of internationalization have broken down and obviously an arms race is starting, everybody has seen it even at that time, what do you think will happen? I would say, if the arms race goes on, we will have a war in ten or fifteen years. Defacto, the arms race went on and we did not have a war for forty years and probably for another five or ten years, I hope, because that gives us time to change. I was surprised that the world was still kept in equilibrium during this terrible arms race, and through the modernization of weapons, through the new inventions which were much, much, much much more efficient than everything we have done forty years ago, ah, that this still has not yet led to an explosion, makes me a little, just a little optimistic. It makes also my conscience a little better. Maybe we did something good between 1943 and 1945.