Oral History Transcript — Dr. Thomas Gold
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Interview with Dr. Thomas Gold
Dr. Thomas Gold; April 1, 1978
ABSTRACT: Childhood in Germany and family background -- competitive spirit; war years -- internment and radar work with Bondi and Hoyle (1942-1945) at Cambridge -- development of theory of hearing and steady state theory; at Greenwich (1952-1956) -- research on lunar surface and terrestrial dynamics; positions at Harvard and Cornell -- involvement with Arecibo; involvement with governmental agencies including NSF and NASA -- changes in government funding. A major part of the interview covers the development and reception of the steady date theory.
Weart:This is Spencer Weart interviewing Thomas Gold, on April 1st, April Fool’s Day.
Gold:I won’t use that opportunity.
Weart:Please do not. Well, I know that you were born in Austria, in Vienna, in 1920, but I don’t know anything else about your family. Who were your parents and what did they do?
Gold:My father was a well-to-do businessman in Vienna, and I lived in Vienna until 1930 when I was ten years old. He was the director of one of the largest Austrian industrial organizations; called Montana, which was a mining and metal fabrication, metal-working industry.
Gold:Yes. Then in 1930 the family unfortunately moved to Berlin, where he became director of another large company. I don’t know to this day why he made the move, but no doubt it was a financial improvement or something for him. So then in ‘33, when Hitler came to power, of course we decided that we would have to leave, although being Austrians; we were not at that stage persecuted. I was 13 at that stage. I went to school for three years in Berlin, went to what was in those days an awfully rough sort of school. I don’t know if you have any idea what Berlin in the thirties was like, but there was very rough violence.
Weart:You mean for Jews, or just in general?
Gold:Well, in general. You know, street fights and very unruly in every way.
Weart:This was a gymnasium?
Gold:Yes. Since you’re interested in me, I’d like to tell you my own career there was the following: I had been in my early school years a bad student. I started out in Berlin also as a bad student. At the age of ten I was generally the worst of a class of 50 or 60, the worst who still got promoted to the next year. Because it was a very rigid system; if you got below a certain thing, then you were not promoted to the next year. It really was enforced. I was always the one who had the lowest marks that just passed. Except then at the age of 12 we started geometry, which was the only sort of mathematical subject — the arithmetic we’d done I was no good at — but then we started Euclid, and Euclid absolutely fascinated me from the word go. I remember just being fascinated with every new Euclid proof, the formal Euclid proof kind of thing we did, you see.
Weart:Beginning with axioms and so on.
Gold:Yes. I found that absolutely fascinating, and immediately was the best in the class of 50 or 60, to everybody’s great surprise. Having been absolutely terrible at everything, suddenly there was a new subject and I was absolutely the best. So the teachers approached my parents and said that up to now they had spared me because they felt I was a little bit below par mentally, but now that they realized I was not below par mentally they would step on me much harder. My parents remember that story very well. In fact, on one occasion at the age of 12 I was even in the situation that I had not done my homework, was called to the front as was common then, to the board, “Prove so and so, prove a certain theorem,” and I had not studied it; and on the spot invented a proof. Which however was not the one in the textbook, and which the teacher had never heard of before. He was absolutely dumbfounded. “Where did you get that from? It’s correct, but where did you get that from?” Just as I was up at the front there. So then ‘33 came and after a little while my parents decided that I would have to leave the Berlin school.
Weart:May I interrupt to ask what was your parents’ education?
Gold:My father was a doctor of law. He had had a very rapid career as a businessman, an enormously rapid career from a sort of young assistant in this large industrial concern literally in a few years to being the general manager. Previous to that he’d been in World War I as a lieutenant.
Weart:What was your mother’s background?
Gold:My mother was of German, non-Jewish origin. Her father worked on the theatre stage — planning the appearance, painting the thing and so on —
Weart:I see; the set.
Gold:The set, yes that was his business. And my mother had been a very successful child actress, chiefly at the age of, I don’t know, 9, 10, 11. She was very successful apparently. She also later did some acting, but I don’t think that was all that successful.
Weart:Did you have brothers and sisters?
Gold:I have one sister who is five years older than myself. She’s still alive.
Weart:Did you have any formal religious training when you were a child?
Gold:No. As I say, my mother was non-Jewish. My father was brought up in a Jewish household, but was very opposed to any kind of religious education. And so am I.
Weart:Did you read a lot in your childhood? Were there any particular science books or any books that influenced you?
Gold:Later, yes. At this stage, no. Up to 13 I read detective stories, in the class, under the bench. That was my chief occupation. That’s why I was so bad in most subjects: I loved reading detective stories.
Weart:There was no particular feeling about science during your early home life?
Gold:No. And my parents were not really science-oriented. Well, I was very good at fiddling with things. I had a little Whims Hurst machine, and I built myself, even already at 12, working radio sets, and even a poor but still functional remote control boat.
Weart:Radio remote control?
Gold:Radio remote control boat, yes. It didn’t work very well, but it did have some remote control to it.
Weart:I see. Tell me then about leaving.
Gold:So then I left and went to a very good school called Zuoz College, in the Engadine in Switzerland. That’s a school with 130 or so boys, a very high-class Swiss school, high-class in every way I mean, slightly snobbish, but also really first-rate for teaching.
Weart:A boarding school.
Gold:A boarding school, yes.
Weart:Your parents stayed?
Gold:Well, they stayed part of the time in Berlin, but then they knew they were going to leave, and my father was in the business of trying to find himself a good job elsewhere. You couldn’t take much money out of Germany immediately. I remember a terrible situation, right after the first really wild pogrom, as it was called. We left on a train, in a hurry; then came back later, because it wasn’t all that disastrous — for us at least, because we were Austrians, and Austrian passports were still protecting us. But we left Berlin in a great hurry. My father came home from work and said, “Get the children, get just a few things in the suitcase and off to the train station.” That’s what we did, and we were in the train — well, I shouldn’t tell you anecdotes like that —
Weart:— finish this one —
Gold:We were in the train together with a very wealthy business friend of my father’s. He was German Jewish and therefore absolutely scared, correctly so as it turned out, because he was later murdered. He told my father, “I don’t want to involve you at all, but I have a very large sum of money and gold coins and so on stashed away on this train, but not on my person. But since I don’t want to involve you in any way with knowing it, I won’t tell you anything about it. He was yanked off the train at the border by the German military. We went on in the train. My father searched desperately in Czechoslovakia through the train, and found nothing. My father’s friend was allowed to leave the next day. Searched through all the railway yards in Czechoslovakia. Poor fellow never found it again.
Weart:If only he’d told you where it was.
Gold:There’s some very wealthy cleaning lady in Czechoslovakia.
Weart:Well, continue with your education.
Gold:At Zuoz I was immediately the best in my class, and continued more or less the best in my class in all subjects.
Weart:Because the school somehow was different enough?
Gold:It really spurred me on. And also the fact that I was so good in geometry immediately gave me a sort of status, you know, gave me the self-respect all of a sudden and the interest in excelling. So suddenly I was the best in all subjects, even subjects that I didn’t like.
Weart:When did the interest in science come along?
Gold:There, in Zuoz, I was obviously very much interested in physics. But I suppose the mathematics was taught much better than physics there, and I was probably really a little more interested in mathematics than in physics, in my years in Zuoz but also in physics.
Weart:Did you have any outside reading in physics or astronomy or whatever?
Gold:Not in astronomy, at that time — well, I don’t know exactly. Yes, I read Eddington’s and Jeans’ semi-popular books, sometime between the ages of 15 and 18. I read all the stuff of that nature.
Weart:I see, and also popular physics?
Gold:Also physics, yes, quite a bit. Also, by 18 or so I read a lot of biology books. I was interested in the more physical aspects of biology. I later worked in theory of hearing in fact, and that had its beginnings already then, that I was interested in that kind of thing. So really, if one wants to attribute anything to anybody’s writing, I suppose Jeans’ and Eddington’s books — which are more than just astronomy, because quite basic physics gets involved in that — had the largest influence in that respect. In any case, Zuoz gave me a good start, in that I was really persuaded that I was clever. You see, that’s really what makes all the difference. Also, I was good at sports, to the extent of being, in my last year there — although I was not in the oldest class, because I left as it turns out a year before the abitur, the final examination — I turned out to be the best skier of the school, which happens normally in the eldest class.
Weart:Right. In Switzerland there must have been a lot of skiing.
Gold:We were all very good skiers. I skied in some of the local area races. It was real tough skiing. I jumped on the big ski jumps. And the fact that I was so good in skiing also made a big difference to my development, as I now see in retrospect. Just anything that I started I became very aggressive at, that I wouldn’t be beaten by anybody; and that became a sort of obsession with me for a major part of my life. I suppose at this stage it’s wearing off a little.
Weart:I see. You had the self-confidence.
Gold:And absolute unwillingness to be beaten in anything.
Weart:Where do you suppose this comes from?
Gold:I don’t know. But I was terribly aggressive in any games that I played. I learned squash, I became very good at that. But then, the games that I was not immediately competent enough to get the leading position in, I just wouldn’t go on with. I loved to play chess, but I had to make the decision — and I was quite good but, you know, it became clear to me that I wasn’t going to devote that much effort to make it a real career —
Weart:When I was here as an undergraduate, I made the mistake of having as a room-mate the president of the local chess club.
Gold:It becomes an obsession.
Weart:After a number of games with him, I just lost my taste for chess.
Gold:Yes. I thought that maybe I could become good at chess, but it would become a very major thing, like it was for some of the boys who did it. But to fiddle around with it, and find that some others could beat me, that wasn’t — so I gave up. As I look back over my career, it was absolutely typical that I would just not take any kind of a defeat. Which no doubt had a good effect on making me learn things, and spurred me on.
Weart:You certainly have entered a number of fields, at any rate. It hasn’t made you restrict yourself to just one field.
Weart:Which I think it might, in some cases.
Gold:Yes. So then, I left Zuoz at the age of 17, from the ordinary curriculum. By then my parents had settled down in England. Then I had to learn Latin, because I’d been in the Realschule, which does not teach Latin. Zuoz had the options, but unfortunately when I started, I didn’t know that I would need Latin. But as it later turned out, I wanted to go to Cambridge —
Weart:Why had you picked a Realschule rather than a gymnasium? Was that discussed in your family?
Gold:Because I was more interested in science. And on the continent of Europe it wouldn’t have been important to have done Latin, you see, but to have done more mathematics and physics and so on was of more interest to me. But then when we landed in England, the situation turned out that the universities there demanded an examination in Latin. So I then went back for one semester and had a rapid coaching in Latin, and then I went to some other coaching school in Britain, had a miserable time, had to learn what it took to get through the entrance examination for Cambridge. The mathematics of it I found very easy, although in fact, in detail I had to learn different things from what we had learned in Zuoz, but I went to a coaching place for a short time and learned that. The Latin I had to learn completely from scratch and that was quite an effort, of course.
Weart:Did you expect from an early age to go to a university?
Weart:It was expected in your family.
Gold:Well, certainly from the time that I was a good student in school, yes. If you go to a school like Zuoz and you are the best in the class, certainly one expects it, there’d be no question. Most of the kids from there would go on to university anyway, but certainly the best in the class, it would be most surprising if he didn’t.
Weart:Was it any burden for your family, by the way, or did your father land on his feet in England?
Gold:We weren’t as well off as we’d been before, but we were reasonably all right, yes. So I don’t think it was too much of a burden.
Weart:Tell me about Cambridge, then. I notice you got your bachelor’s in mechanical sciences in 1942.
Gold:My Cambridge career was very badly cut up, because I went to Cambridge just as the war started, September, ‘39. On the 12th of May 1940 I was interned as a potential enemy alien.
Gold:Having an Austrian passport. At that stage I didn’t have an Austrian passport, because in ‘38, at the Anschluss, it was German. By then we’d thrown away our Austrian passports and had taken stateless papers in Britain. But the British did that terribly badly, this business. First, they investigated everybody of foreign nationality, in the first months of the war, and gave us, of course, a clean bill of health, you see. But then, in the excitement of the German invasion of the Netherlands and Belgium and France, they suddenly gave orders to the local police districts to use their own judgment. The local police districts had done nothing to investigate people. It so happened that I was in Cambridge, where all the ex-enemy aliens were interned, on the order of the local police chief, and my parents were in London where they were not interned.
Weart:You were sent to an internment camp?
Gold:I was sent, first for a few weeks in Britain, then to Canada on a ship from Liverpool, under frightful circumstances with everybody on the ship getting dysentery. I arrived in Canada emaciated, in awful condition. So did most of the other 800 or so people interned in that ship, under really horrible circumstances. You wouldn’t believe what it’s like to be treated as an enemy alien, even in Britain. I hate to think what it’s like in countries that are even rougher, because the British after all are fairly decent by comparison. But frightful circumstances — just pushed into the hold of a big cargo ship with barbed wire entanglements all above us, so if the ship had been torpedoed we wouldn’t have had a hope in hell of even getting to the top. Densely packed like sardines there, three layers, on the floor and on the tables, hammocks up above, and in the whole place, I don’t know, there were maybe ten toilets for 800 people, and they all had dysentery. You can imagine what it was like, just appalling. Then we were in Canada for seven months or something like that, eight months. There the circumstances eventually got to be a little bit gentler. It was pretty rough overall, but at least health-wise we got reasonably fit again. I organized a lot of sports activities there. I became very proficient at high jumping. I could jump substantially over my own height, which nowadays doesn’t amount to much, but in those days it was quite something. And we ran a sort of camp teaching business in the physical sciences, in which one of the chief persons was indeed by then my good friend, Hermann Bondi.
Weart:Ah, because he too was —
Gold:— because he too was interned in Cambridge. I met him on that concrete floor, the first night of internment, in a little place near Cambridge where we were shipped on the first evening. It so happened that the person who had to bed himself down (next to me) on a bare concrete floor without a blanket, as we all did, was Hermann Bondi. We became good friends then. He was substantially ahead of me, I think two years — he was a year older than I, but was two years ahead in the university, I think, because he’d started a year earlier than I. He was already known then as an outstanding mathematical genius, which is what he is. But he also knew quite a lot of physics, mainly very classical type of physics; dynamics was his strength.
Weart:What was he like as a person at that time?
Gold:Very full of wit and humor always; always very cheerful, even in quite tough circumstances. Personally he’s a very robust fellow. He was quite strong; nothing shakes him, tough in every way. He went through this internment misery with great fortitude. He taught a lot of people what he knew of mathematics, which was already quite a bit. I learnt a fair amount of dynamics and some aspects of mathematical physics in internment from him, and also got more interested. Also, there is something slightly intangible that one has to say. It was Bondi’s outlook of immediately demanding to be at the top in any mathematical subject — he gave one immediately the right impression of from which side to look at the problem to really see through it. He’s awfully good at that. There’s always a very penetrating way of looking at any problem, and he taught me that outlook. Not just the details of the few cases. That I learnt from him; that’s not so important as the general outlook, that really, in the physical sciences, you have to think around a problem from all sides until you find a way that really penetrates it. He understood that very well. If I teach people any physical subjects now, I very consciously try to copy that. But on the other hand, I must admit that I don’t find all that many students, quite frankly, who are as open to this suggestion as I was. I find it hard to persuade students to put that much effort into finding the best way of understanding a thing in their minds, you see. Most people are satisfied when they’ve approximately understood it.
Weart:Were there other physicists or scientists in that camp that you knew?
Gold:Oscar Buneman, who is a plasma physicist at Stanford now. He was there, and he was a great puzzle man. He invented all kinds of sophisticated mathematical problems, and we enjoyed that. In internment that was the sort of thing one could very well do. We didn’t have any books, and so teaching from memory and puzzles was the kind of thing we did.
Weart:Were there very many people involved in this, or just a few of you?
Gold:Yes, there were two or three others, four or five of us maybe. Sometimes we had classes that were maybe as many as 20 people. I don’t think that many of them were really all that serious about it. But we organized little lectures and so on. Then I was sent back and released. Bondi was sent back by some different route. I don’t remember any more why, but we were split up in some way. He also got back a little later than I, and was also released. The British by then had looked through our papers or something. So then, most of a year had gone by. I’d had a part of the first year as an undergraduate, and then virtually none of the second. Then I entered into the third; it’s normally a three year course.
Weart:You just kept on as if you had been there all along?
Gold:Yes. But by then I must say that I was no longer good at it, and I’d gotten absolutely bored with the mechanical sciences course. I knew a great deal more of the physics by then. Signing up for mechanical sciences was a great mistake; I should have signed up for physics, but my father had not really believed that I was all that bright. He always said, “Well, all parents think their children are bright, but we mustn’t make that mistake,” and “If you’re not in the very first class as a physicist, you wouldn’t be able to make a living, so why don’t you become an engineer?” because I was obviously quite good at engineering things. You know, I built things, and once I had wanted to become an engineer. So I took the engineering. But as I say, in the third year I’d really lost all interest in the matter. By then I was reading much more scientifically-minded books, and did the engineering course as a sort of sideline.
Weart:I see, so you were definitely oriented toward —?
Gold:So, having lost one year and lost interest in the engineering, I was really learning physics. Then I did very badly in the final exam — again, my usual style of just the barest minimum to get my BA degree.
Weart:In mechanical sciences.
Gold:In mechanical sciences.
Weart:Had you already decided at this point to make your career specifically in physics?
Gold:In physics, yes.
Weart:I see. What did your family think of this as a career choice?
Gold:Well, my father wasn’t — at that stage; he wouldn’t have interfered in any way. He didn’t say. He was disappointed that I didn’t get better grades in the mechanical sciences, but he knew that I was more interested in other things, and he knew that I was quite good.
Weart:I suppose with the war it’s hard to say, but what sort of life did you expect to lead as a scientist? Did you picture any career or type of life?
Gold:I was still very much instilled with that same spirit, that if I did anything it would be the best right away. I found it very hard to reconcile myself ever to the situation of not being right on top, effortlessly and right away. And any time that was not so, it was a great shock to me.
Weart:So you were to be, what a physics professor at Cambridge?
Weart:I wanted to ask, you were in the mechanical sciences, but did you have any contact with the physicists or astronomers?
Gold:No, not at all. In my last year, you see, even Bondi had left Cambridge. He had finished. Because he was such a brilliant mathematician, he’d already taken the final, the BA degree, before his internment, you see, and had done what’s called Part 3 in mathematics, which are sort of postgraduate courses, in the final time he was there. Then he left and went to the Admiralty, to the radar establishment, which was then a very secret business, the radar design for the Admiralty. There, as a young brilliant mathematician, he was put into the theory section. And the theory section was headed by one Fred Hoyle.
Weart:Hoyle himself was not so old at that time.
Gold:No, I think he’s two years older than Bondi. He was also a very brilliant mathematician, and the British were very good at recognizing good people in these circumstances. He was put in charge; he was in charge of the theory division of the Admiralty’s radar establishment.
Gold:At Witley. Hoyle had immediately made a very important contribution to radar, namely, he had devised a very simple plan of how to find the height of an airplane with long-wave radar. You see, with very long-wave radar you had no directional capability worth a damn. But he had immediately found how to find the height of a plane by using the interference lobes between the antenna on the ship and its reflection on the water. Counting the lobes as the plane approached, you saw the signal fade in and out, and he plotted the correct kind of diagrams for the naval radar officers to use, and they immediately could determine the height of a distant plane quite well, at a distance of 100 miles or something. So that was his responsibility right away, and that was what got him promoted to be immediately the head of the theory division. Then Bondi was there, and so the moment that I finished in Cambridge, in the spring of ‘42, I tried to join him, and he tried to organize from Witley to get me there. But it took many, many months, because the security people didn’t take the case too seriously and it took many months before I got my security clearance. After all, the whole thing was pretty absurd, to be in internment at one time and then a few months later to go to the most secret defense establishment. But still, eventually they succeeded in getting me there. I spent meanwhile some time working as a farm laborer; I had to do something for the war effort, you see one way or another. So I worked as a farm laborer in the Lake District and was a lumberjack. Incidentally, my ambition, even as a lumberjack, in pre-chainsaw days you understand —
Weart:Yes, with a big axe.
Gold:With a big axe. I worked in a professional lumberjack camp cutting down plantations for pit props for the mines. So they were all standard sized trees and they paid piece rates, so much per tree. You had to cut it down and then strip the branches off. Then the foreman came around and counted, he marked them with a sign and you got paid according to that. The second week, I got the highest pay of the camp. The first week I was so sore, you couldn’t imagine, of course.
Weart:Yes, blisters and so forth.
Gold:Yes. The second week I got the highest pay in camp. And the professionals started to get annoyed with me, because it would depress the rates if one showed how much one could cut down in a day. Some of these other fellows, of course, were actually Herculean compared with me, you see, beefy great fellows. It was enormously easy for them to swing that axe.
Weart:I’m sure they had their own culture there.
Gold:Yes. But it just showed me how the handicaps of size and strength were not nearly as big as the mental ones.
Weart:So how did you get into the radar?
Gold:By the end of ‘42 I got accepted by the Admiralty, was put into the theory division, and worked there with Bondi and Hoyle and Cyril Domb, who’s a well-known personality now in thermodynamics. Before very long I was made the deputy head of another section. So I left the theory section and became deputy head, a very substantial promotion, and was in charge of new radar devices, new trickery from radar. We built there, I think, the first reasonably functional moving target indicator system.
Weart:You were quite close to the instrumentation itself, then.
Gold:Yes. I’d done many experiments, I’d conducted trials, and so on, and understood the whole radar business pretty well by then, and was now in charge of designing and building new kinds of radar tricks. The chief among them was the moving target indicator system of discerning which targets are stationary and which are moving. I did that, designed mercury acoustic delay lines. My acoustic delay lines were the first ones that really worked; other people had tried but mine were much the best. I also invented and built a lovely little gadget for plotting, from a contour map of the ground, the land that the radar set would see from the sea. It was then used in the [Normandy] invasion, by giving people maps of what they would see from the ships when they approached the shore. The ships would use that to precisely position themselves for the landing. Different schemes were used. Mine was not the only one, but I would say that mine was by far the neatest way of doing the job. And so we furnished such maps. I was not directly concerned with the final furnishing of the maps, but only with the design of the method.
Weart:I understand. What was the atmosphere of this place? This was at Witley?
Gold:Yes. Well, it was a pretty easygoing business, I thought. Bondi, Hoyle, and I were probably pretty careless and easygoing in our work. Sometimes we’d work very hard. Sometimes we’d turn up hours late to work.
Weart:Did the three of you discuss things other than radar work?
Gold:Yes. Hoyle was very interested in astronomy, and he was chiefly responsible for getting Bondi and me interested in the field. In the first place, when he started to work seriously with Bondi, he immediately realized, as everybody of course very quickly did, that Bondi was just a wonderful problem-solver. Even though Hoyle was also in the front ranks for this, but nevertheless nothing like as quick as Bondi. And so Hoyle would give him definite mathematical problems in astronomy. I remember the kind of scenes. Bondi and I shared a little house, a miserable little house that we’d rented. Accommodation was not too easy.
Weart:Is this the one that Timothy Ferris talks about in his book, THE RED LIMIT?
Gold:Timothy Ferris? I don’t know.
Weart:He wrote a book about cosmology. He told how you and Bondi (maybe he got it from Bondi) had a cottage whose windows were frequently blown out by the bombs that fell.
Gold:That’s right. That’s correct, yes. Hoyle stayed there some of the time, Bondi and I all the time. Yes, the windows were blown out frequently by bombs that were dumped, time-fuse bombs that could not be defused, that were returned to the local military airfield because the hydraulics of the plane didn’t function or they were shot up. The planes would come back and they’d have to rip the bomb doors open as fast as they could and dump the bombs somewhere. And the place where they dumped the bombs was about 100 yards from our house. It was pretty frightful.
Weart:This made that house cheap, I suppose.
Gold:Yes, that’s right. It was absolutely under the runway, too, so every morning at 5 o’clock you’d hear those planes staggering, as heavily loaded as they could be with bombs, going off for the French coast. They’d just clear the roof top. We literally were just at the end of the runway, underneath the planes taking off. One morning, the following scene took place. I had eventually managed to sleep through this ordeal every morning at 5 o’clock, you see; it was terribly loud, but you get used to it. One morning, however, I woke up with an explosion, a very violent explosion, which had loosened yet another piece of plaster on the already heavily cracked ceiling, and there I was lying in my bed, having evidently slept with my mouth open, with a piece of plaster in my mouth. I was spitting out the plaster, and Hoyle comes in, as he was staying with us — Hoyle opens my bedroom door and he says, “Did you hear that?” I said, “Jesus Christ, how could I not hear that? It’s shaken the house, shook down the plaster.” He said, “Yeah, I heard the planes take off, and then one of them did not continue, but that was about a quarter of an hour or 20 minutes ago and I went back to sleep.” “One did not continue,” meaning it crashed on takeoff, you see. It crashed on takeoff quite near us, burnt, and eventually heated up the bombs so after 20 minutes they exploded. Hoyle’s calmness, of going back to sleep when he heard a plane making a takeoff-noise and not continuing, was extraordinary.
Weart:I wanted to ask you, did you talk about cosmology in particular?
Gold:Yes, especially in the last year '45-'46. Hoyle was all the time talking about, what do Hubble’s observations really mean? The word “Hubble” was on his lips a hundred times a day.
Weart:Was this your introduction to these problems?
Gold:Not really, because as I say, I had read by then everything that Eddington had written. But that sort of stimulated me to think on a day-to-day basis about such problems, yes. With Bondi, Hoyle worked on mathematical problems. Bondi was so far ahead of anybody else in mathematics at that time that if you had him around, you couldn’t bring yourself to do anything yourself, you see, because you’d just ask him and he’d do it right away. So with Bondi he worked on mathematical problems of gravitational accretion —
Gold:On stars, yes, problems which Hoyle had worked on with Lyttleton before, but then Bondi carried the subject quite a lot further. I remember many an evening in our house in Dunsfold, where Bondi always liked to sit cross-legged on the floor in front of the open fireplace, which was the only source of heat; Bondi would sit on the floor and Hoyle would sit in an armchair just behind him, and more or less kick him into activity all the time. “Now, work out this.” Hoyle would sit there above him and look over his shoulder, Bondi would sit there cross-legged on the floor; “Now do this, now do that,” and Bondi would then feverishly work this out, and he’d scribble at a hell of a rate.
Weart:You were more or less a spectator?
Gold:I was more or less a spectator to that. I remember that I would sit there frequently reading and just looking up and listening a little bit to what was going on. But that went on a great deal. The three of us were certainly pretty much the intellectual set there.
Weart:Who else was there? Were there other physicists higher up?
Gold:One person who was there only in the first year that I was at Witley — he was not at Witley, although Witley was his parent establishment, but he was in a distant place, in charge of the antenna section — was a person by the name of Maurice Pryce. He was senior to Bondi (at Cambridge). I don’t know which of the two had done better in the mathematical Tripos examination, but Maurice Pryce was one of the previous heroes, and Bondi was the hero in his year.
Weart:Oh, was Bondi First Wrangler?
Gold:He would have been, under the old system. He was certainly the top person in his year.
Weart:And Pryce was before.
Gold:Pryce was before, yes.
Weart:The people you mainly were dealing with here were Navy people then?
Gold:Well, it was a civilian-establishment that we were in, but —-
Weart:— with whom did you interface? The people who were coming to you with problems, or to whom you were trying to sell a device?
Gold:This was with the Navy, yes.
Weart:And how did that work?
Gold:I had a fair amount. On the whole, we were just designing sets, and then they would be put into production.
Weart:I know people at MIT Radiation Laboratory had to practically go out and sell their sets to the military. You didn’t have this sort of problem?
Gold:No, we didn’t. That problem had been solved already. But on the other hand, I had a fair amount of contact with the Navy directly on such problems as how best to use the sets, for example, when the snorkel got going. I did a lot of trials of how to detect that miserable little thing.
Weart:Could one detect it?
Gold:One could. But all that I could do was optimize the circumstances; there obviously wasn’t time to install any new sets. The turnaround time for that was, even at the quickest, a year. But at least I could optimize the circumstances of adjustment and height of mounting and so on.
Gold:In fact, I suppose I contributed a bit to the detection of snorkels.
Weart:Tell me (this is a question I ask everyone), when did you first learn that atomic bombs could be built?
Gold:All I clearly remember about it is the following thing. I was in the company of a professor of aeronautical science at Imperial College by the name of Hyman Levy. He must be dead by now, but he was a famous man then. A year before the atomic bombs were deployed, I remember saying to him — you know how memory sometimes works better for things that one did? I mean, I can remember better talking to this man than anything; I can’t really remember what I knew at the time. I must have known something. I remember my conversation with him very clearly. The conversation was that he said in scientific circles there had been some discussion whether one could make a nuclear bomb. I said, “Yes indeed, I suppose one could make a nuclear bomb.” He said, oh, he had heard that some scientists have said that, but he thought that was quite inconceivable. And I said, “No, I think it’s entirely possible,” and gave some perhaps not very meaningful arguments as to why I thought it could be done. The arguments did include the discussion of neutrons, because he had said something about the horrendous temperatures that you would need in order to make any reaction go. And I said something like, “That isn’t true if there are neutrons involved.” So that much I had understood. Moreover, I said to him, “And I do suppose that they are building one, because various high-grade scientists have left the radar field,” which after all was pretty important too. They had been shipped off to Canada, including the great Maurice Pryce. I said, “I can’t really think of any other subject that would be important enough to take him away from the excellent work he was doing there, if it weren’t a nuclear bomb.” I remember saying that a full year before they were deployed.
Weart:What was your reaction then when you heard about Hiroshima?
Gold:Dismay. At that stage, no one was really afraid any more of losing the war. I was distressed that it had been used on an unsuspecting population.
Weart:Did that have any special meaning to you as a scientist?
Gold:One would be tempted to say yes to that, but I don’t really think so. I think I just thought immediately of the situation, that if this new weapon now exists, it’s a mistake that we used it first. I was elated that it existed, and therefore that science had made this — that our side had, through science, gained this enormous military advantage. Of course one was elated at that. And in those days, no doubt we would all have fought for an atomic bomb program if we had been asked about it.
Weart:Because of the Russians or —
Gold:No, by no means, but because one’s frame of mind was very military in those days. I mean, you just absolutely thought that you wanted the military power. Having only just beaten the Germans, it was still a very fierce sort of outlook. At the same time, myself and many others with whom I discussed these things thought that it should have been dropped as a demonstration in the first place; why wasn’t it dropped, with some leaflets over the cities saying, “You go and look at the so-and-so forest that we’ve destroyed, and unless there’s a peace signed by tomorrow your cities will look like that.” You see? As we later learned, many scientists at Los Alamos had insisted on the same thing.
Weart:This idea came up independently, spontaneously?
Gold:Yes, yes. And in fact, the story goes — I don’t know how correct — that at one stage, the scientists at Los Alamos had the assurance, which was hedged in some way, “if at all possible” or something, that the bomb would be used as a demonstration first. When one inquired later as to why it was not so used, then the answer was, “Because we weren’t all that sure that it would go off, and we didn’t dare risk dropping a fizzler on a forest.” They didn’t have to drop the one on Nagasaki. That was absolutely wanton.
Weart:Well, tell me now about being demobilized and going back to Cambridge?
Gold:Well, then I was stuck in the Admiralty. I tried to get out when the war was over, and was there for a whole year more, trying to get a job. By then I had a good reputation to my name, as the chief of new devices; I built good gadgets and so on. I first tried to get back — I wanted to get back to Cambridge, for one thing because by then Hoyle and Bondi were both there again, and it seemed the obvious thing to do. I was by then obviously going to attempt, at least, a career in some scientific job, and so that’s what I did. So I first tried to get back there, having persuaded the director of the Medical Research Council that I would be able to construct a high frequency acoustic imaging machine, which could be used in lieu of X-rays to look through people.
Weart:Well in advance of its time.
Gold:And which could be used — but the Medical Research Council was not so interested in that aspect — for material testing of welds and so on, engineering-wise. High-frequency acoustics is much better than X-rays for that, because a crack is completely opaque to high- frequency acoustics, but it hardly changes the opacity for X-rays. So I thought that was a wonderful thing for crack testing of castings and so on. I designed gadgets that were in the nature of a water- tank with scanning machinery and an assembly to go around it. It was a very complicated thing. Because I had built the acoustic delay lines, you see, and I was really by then probably the expert in ultra-sound in liquid, in mercury or water. As I say, I’d undoubtedly built the best mercury delay-lines, and so in the course of that had done a lot of experimentation in solids and liquids. I’d gotten money assigned by the Medical Research Council to have a job in the Cavendish Lab in Cambridge in this subject. I had been accepted by Sir Lawrence Bragg to do this. Then shortly before I was actually to take up residence there, I’m informed by Ratcliffe, who was the deputy to Bragg in running the Cavendish Lab — I don’t know whether you’ve come across the name J.A. Ratcliffe. He was the promoter of Ryle. He was a great committeeman, would organize every committee that he could lay his hands on, and was terribly skillful at making any committee do whatever he wanted, like putty in his hands. He really ran the Cavendish, and Bragg had nothing to do with it — Ratcliffe suddenly came out with a statement. At the last minute they realized they didn’t have enough space, and had to turn down this Medical Research Council grant, and I could not be accepted.
Weart:Why was that?
Gold:[shrugs] It didn’t fit in with him. I think Bragg had been interested in doing it and he, Ratcliffe, was not. Ratcliffe altogether from that time on was more or less my enemy. Nevertheless, I was determined. It’s an awful shame because it is exactly this scheme which only now, 30 years later —
Weart:— is going into common use, yes.
Gold:It’s just now being used, only this last two years. It works fine, of course, a lovely device. Now it’s being done because of the realization that X-rays are harmful. But in fact, it does many things that X-rays don’t do. Soft tissue, you can do lots of things with it. You can put a little nitrogen into the abdominal cavity and see all the gut outlined, for example. With X-rays you can’t because that doesn’t make any difference.
Weart:You went to the Zoological Lab then?
Gold:No, not at first. I was still determined to get to the Cavendish. I then applied for a job that was advertised, to assist in the construction of a high-power magnetron for the new accelerator. i wasn’t all that skillful at vacuum-technology, but still I got the job, just on the basis of my record at Witley. I got the job, and Ratcliffe was not able to keep me out of that. So I worked for a few months on the magnetron-design, but the work was not very thrilling. It was a purely technical job. I probably imbibed an awful lot of thorium at the time, now that I think about it, because I made big thorium cathodes, forming them on a potter’s wheel myself with my hands, and I had no idea that the stuff was dangerous. I’m surprised I’m still alive. Nobody had taken any notice of this level of radioactivity. At about that time, in 1947 or ‘48, while I was working in the Cavendish Laboratory, I thought about the problem of methods of tracing out particle-tracks like cloud-chambers. I wanted to find areas of work for myself in the Cavendish. The idea I came up with was taking a liquid and expanding it rapidly after an ionizing track has passed through it. A flash of light would then slow up the bubbles that would form, first on the line of the track. This would allow a detection of tracks when higher density was needed than that in a cloud-chamber. I thought of setting up a tiny experiment, with perhaps a cubic centimeter under a microscope, and a flash tube, and then seeing tracks from a radioactive source. I presented this idea to a group in the Cavendish, with a view to getting permission to set up this experiment. It was Professor O.R. Frisch, Shire, Kempton, and I believe, but I am not quite sure now, Denys Wilkinson. They listened to my story, and then Frisch, who was a good friend of mine, said: I am sure your scheme would work. But we would not have any need for it. Between the photographic plate and the cloud chamber we have all the detection devices we require. I even explained that liquid hydrogen would be a possible liquid, with the advantage that for any event the target nucleus would be known. Even that did not persuade them that this was important. I was stupid enough to accept this. A few years later (in 1951 or ‘52, I believe) the bubble chamber was invented by Glaser. I reminded Frisch of my proposal. He remembered the story well, and I felt that he should have explained this in public. Later, when Glaser got a Nobel Prize for this invention I reminded him again. I was a little annoyed that he made no move. Had I been told it would not work I would have struggled to show otherwise. But to be told that it would work but would not be used, that had really discouraged me. Then while I did this work I wasn’t very interested in, I worked with R.J. Pumphrey, who had been the deputy scientific head of the Witley establishment; he’d been above us all. He was a great biologist. Why a great biologist would be deputy chief scientist in a radar establishment is not clear, but in fact it was very sensible. They just took very good scientists from whatever area. The radar was new to all of them, and the good ones learned very fast; and he was among them. R.J. Pumphrey was a very fine person. He’d also gone back to Cambridge and I’d retained my contact with him, and he used to treat me as sort of tame physicist to the zoology lab.
Gold:I would be asked all kinds of physics questions in relation to, among other things, sense organs that they were investigating, but also various other things. That eventually got me started in the hearing business. We made another application on this topic, to the Medical Research Council, and got a grant for me to work on hearing. So I left the other job at the magnetron and joined Pumphrey in the Zoology Lab, and we worked there very happily for three years or something like that, on hearing.
Weart:Were you thinking seriously of going into biophysics?
Gold:No, I think not. I think that I thought just that this is an interesting job. By the time that I got the grant and took on this job, I had already firmed up a novel theory of hearing, which I’m absolutely convinced is correct. I can tell you about that. In recent times the evidence for my theory has become overwhelming. It’s only that there are no persons working in this field any more, it seems, or awfully little and you just cannot find any sensible physicist or physics-knowledgeable person working in the theory of hearing any more.
Weart:Have you written anything on it recently?
Gold:I haven’t recently, but I’m planning to, because three or four new items of information have come to light that are firmly predicted in my papers, the Royal Society paper in l948. It predicts that one ought to find the following things — and they’ve all been found —
Weart:But only recently?
Gold:But only recently.
Weart:Did the ones that found them know about your paper?
Gold:They don’t know about it, no. It’s absolutely clear; I’ll tell you very quickly what the score is. My story is that on physical grounds it is completely inconceivable that you would have the frequency-discrimination that you have, if the mechanism were merely a tuned membrane in water on a scale of millimeters, which is what it is. The damping that you get out of that is so enormous that the Q or any kind of frequency sharpness that you can get is only like a Q of 5. Every curve would stretch over an octave. And there’s no way in which you could get the frequency sharpness out of it that you subjectively obviously have. Especially, when you think of it, that you can recognize many notes simultaneously; they don’t interfere much with each other. But if you have a very flat curve, then you cannot possibly get the maximum of each of those flat curves simultaneously.
Weart:Right, discriminate them.
Gold:Yes. But we can. So we did a lot of experiments that sharpened up this consideration very much, and left no doubt that at least one side of the frequency response curve had to be sharp to the tune of 60 db per octave at least. Then my answer to that was, anything that can discriminate with that kind of sharpness had to have positive feedback — if it was done with intrinsically extremely highly damped devices. Nature could not beat the viscosity of water, you see, on a small scale that’s very important.
Weart:There must be feedback.
Gold:There must be positive feedback. And a number of effects were already then known that absolutely fit in with the notion that there is feedback there. There’s a micro-phonic potential that has no part in the nerve-conduction, and it wasn’t clear what. It was doing there at all. I said, “That obviously is the action potential for the actuator in the positive feedback-mechanism, with the mechanical —
Weart:You mean a mechanical feedback?
Gold:Electromechanical feedback, using electrical energy applied to what is in principle like a tiny muscle on each element. And this electric potential that appeared was clearly the action-potential for those actuators.
Gold:Those had to be adjusted to be almost oscillatory, but not quite because out of a Q of 5, it had to make a Q of 200. I wrote what I believe was a very good paper on that. I feel very bad about the fact that it is not generally acknowledged. A Mr. Bekesy got a Nobel Prize for what I believe to have been technically very intricate work, but a totally erroneous interpretation and physically incorrect. Not only is it not how the ear works, but also he made gross mistakes in physics. I mean, he didn’t understand how to scale correctly. He did experiments on a large scale, and did not know what he had to do to scale for the viscosity-effect to small scale.
Weart:I see. It wouldn’t be the only Nobel Prize that was given for mistaken work.
Weart:All during this intervening period, you haven’t done any biophysics actually, have you?
Gold:No. I’ll tell you a little bit more about that now that you ask me. I wrote at the time that one therefore would imagine a number of effects. Firstly, one would imagine that there would be some people that would have “objective tinnitus.” Tinnitus is a ringing in the ear. I said, a fault should be possible whereby this feedback- mechanism habitually oversteps the mark and self-oscillates. Because if you are so close to oscillation, there ought to be some people who are sick with one thing or another, so it oscillates. Of course, there are many people that have subjective tinnitus, but that could be just in the nerves. But there should be objective tinnitus, meaning that you would hear the sound outside. Another person would be able to hear it. (Tapping desk with pencil to emphasize point)
Weart:My goodness, yes.
Gold:I said, “That of course, would completely clinch the matter, because you cannot generate —
Weart:— there has to be a driver, yes —
Gold:— There has to be a driver. And I wrote that in the paper. I said, “We were not able to find anybody that had objective tinnitus, but we are searching.” Then I wrote in the paper that some of the hair-cells spanning a certain place ought to be not receptor-cells, as everybody had assumed they were, but actuators.
Weart:They should be different kind of cells.
Gold:Yes. There should be a different kind of cell there, and it should be an actuator. What else did I say? One can look it up, but that’s all written in that paper.
Weart:I see. So somehow you managed to keep close enough in touch...
Gold:I’ll tell you about that. I also said of course that the response curves, when correctly measured, ought to be with an extremely sharp cutoff on the one side. When incorrectly measured, such as by Bekesy, they were flat. He measured it on a dead animal. I said, “Once this feedback mechanism ceased, they’d be flat. But if you did it on a living animal, they’d be sharp.” That was another clear prediction.
Weart:So now they’ve put in neuronal probes, something like that?
Gold:Now they’re able to put a tiny flake of iron on the living membrane of a rhesus monkey and measure by Mossbauer Effect the displacement of that little submicron flake of iron. They find the sharp response curve. Like that. (Pointing to sketch) And the other, they found too. They found all the things I predicted. They found the sharp response curve in the living monkey. They found several families that have hereditary objective tinnitus. A baby of that family, picked out of its crib: it had 12 kilocycles radiating out of the one ear, 14 out of the other.
Weart:Can you hear it?
Gold:People were surprised; they picked the baby out of its crib, it was making a little squeaking out of this ear, another squeak out of that ear. They recorded it. Nowadays of course, they record it on a tape recorder, analyze it —
Weart:— do the people understand what’s going on?
Gold:No. A clear pitched single noise comes out at 14 kilocycles. What do the doctors say about it? First they tried to cure that family by trying to decrease their blood pressure, because they think that it must be the rushing of blood through their blood vessels that is making the noise.
Weart:But this is a very sharp signal.
Gold:It’s a clear, clean-pitched 12 kilocycles. By running a viscous blood through tiny capillaries, you’re going to make a whistling noise — I mean; it’s just so crazy you wouldn’t believe it. By now many, many examples have been found of people with objective tinnitus, especially one family where they all have it. A loud, 20 db, audible signal comes out of the ear. Clean pitch and so on. No question that that’s correct. There is no other way in which you could ever have that.
Gold:You can’t make 12 kilocycles out of any other mechanism —
Weart:— now tell me, how is it that you’ve kept in touch with these things after all this time?
Gold:A very nice person whom I’ve never actually met, his name is Charles W. McCutchen, now at the National Institutes of Health in Bethesda, Maryland, had been told by Freeman Dyson of my theory of hearing. McCutchen is concerned with such subjects, not principally hearing but he’s in some medically related things, and he got very interested in this. Freeman Dyson and Otto Frisch in Cambridge (England) had told him. These physicists believe my theory all right, you see. I can demonstrate it if I give a lecture to the physics people.
Weart:They remembered it since way back?
Gold:Yes, they remembered it since way back, and it seemed quite clear that’s the only way of doing it; no question, the physics is correct, there’s no other way of doing it.
Weart:So this fellow got in touch with you.
Gold:So he got in touch with me when he came across some piece of literature. I think the first thing he came across was that on the basilar membrane of a pigeon, they had found that one set of the hair cells, when investigated by scanning electron microscope (which we didn’t have available then) was identifiable without question as what is called a “kinocilium,” that is, an active fiber. You understand the word kinocilium; the cilium is a fiber, kino is one that is active. It’s like the little cilia that the amoeba has on the outside. So they identified that indeed, in the pigeon’s ear, there is a row of kinocilium, and it is in precisely the location, is precisely the fiber that I described in my paper as being where it would have to be.
Weart:Well, that seems all very straightforward. You’d better hurry and write it up before someone — well, let me interrupt, I want to get back —
Gold:— it was on the basis of this work on hearing, though, that I got the fellowship at Trinity.
Weart:I see, OK. I wanted to ask more about your training and so forth at Cambridge. (brief pause to discuss time left for interview) So, you became a fellow at Trinity College. Tell me about being a fellow at Trinity. That’s not easy to become.
Gold:I wrote a dissertation on theory of hearing.
Gold:No, that’s just for a fellowship. It’s a prize fellowship, awarded on the basis of a paper written specifically for that purpose. In the setup in Cambridge, if you got the prize fellowship at Trinity, it meant that this was so very much superior to a PhD that you did not bother to take a PhD. I might otherwise have done that, but as it was, when you get the prize fellowship you don’t think for a moment of doing anything more formal.
Weart:Tell me, while you were at Cambridge during these years after the war, did you take courses? Did you have any formal or informal training?
Gold:No. Nothing, but then —
Weart:In fact, you’ve had very few courses in physics?
Gold:Absolutely zero. What happened then however was that after two years in the Zoology Lab, I thought that I’d better get myself more permanently set up, and so I applied for and received a junior lectureship in the Cavendish in physics, although my credentials as a physicist on paper were nil. A miserable record as an engineer, and the rest was only my work meanwhile, you see. But with the Trinity fellowship, and —
Weart:— and your radar work —
Gold:And the radar work and so on, I was by then quite well known. So, in fact, I got this. So I taught physics for two years, I suppose.
Weart:Your knowledge of physics must have been fairly patchy.
Gold:It was, yes. But I had to learn to do the teaching, for one thing, and be a demonstrator in a large experimental class, for example. I had to learn to set up all these interferometers and God knows what else, electrical gadgets.
Weart:If you had a Trinity fellowship, why did you take this position? It helps financially.
Gold:Yes. Maybe I started that position before I got the fellowship.
Weart:I have here that you became a fellow in ‘47. You also married about that time. Then you became a demonstrator I think after that. Was this partly for career purposes?
Weart:To establish credentials?
Gold:I suppose, yes.
Weart:In what circles were you moving in Cambridge, physicist circles?
Gold:Yes. Still Bondi, Hoyle, Lyttleton, Runcorn, R.A. Fisher, the geneticist, and of course Pumphrey —
Gold:No. I mean, other than Hoyle; the nearest to astronomy was Hoyle. But no, I didn’t have any contacts. Well, I knew some of them. I knew Redman and Culbert.
Weart:What was the attitude of the physicists toward astrophysics? I know in Rutherford’s day he used to say, “We’ll discover the real things here and later on they can be applied to the stars.” Was there a carryover of that attitude?
Gold:I think not. No, I had the feeling that we had no difficulty in keeping our end up, as it were, among the physicists in those days.
Weart:Did you see yourself as an astronomer at the time?
Gold:No, not really. I must say, I was very vague. I was very self-confident, and always thought that whatever I do it will be all right. I never had any real thought that I might not have a successful career or anything like that.
Weart:Do you recall what journals you read regularly at that time?
Gold:NATURE. What else? NATURE I would read regularly for all kinds of interesting things. I was one of those people who really used NATURE in the sense in which it was intended; there were things in biology as well as in —
Weart:— right, even the pages at the back.
Gold:Yes. But I suppose I read sometimes the astronomical literature too, but not a great deal. In Trinity, you asked me, who did I meet? People that I liked to talk to in Trinity included Lyttlewood, the great mathematician who died very recently, and Bessicovich, another mathematician, and then a personal friend of mine was an historian by the name of Jack Gallagher, who is now the vice-master at Trinity.
Weart:Did you have any contact with things outside the sciences, particularly philosophy? Any reading or contacts with that?
Gold:Not with professional philosophers, no.
Weart:Did you have much interest in philosophy; all through your school career?
Gold:The subject, yes, but I wasn’t spurred on by anything much that I had read. I somehow regarded the way into philosophy from a sophisticated physics education as much more meaningful, right from the start. I was offended by people, in so-called philosophy, who were not really especially knowledgeable about physics and what was understood. When I later worked on some sorts of subjects that might be related, like the nature of time, I had that feeling very strongly. I read some stuff that the philosophers had written about the nature of time, and I think its absolute bunkum.
Weart:What sorts of seminars, journal clubs or informal meetings outside Trinity did you go to?
Gold:(Tapping pencil and thinking) I was very active in the evening meetings. There were two regular sort of high-class physical sciences evening groups that met. One was called the Del Squared V Club, and the other was called the Kapitza Club.
Weart:Right, those were both functioning.
Gold:Yes, I was very active in those. I gave many talks there myself, including one on the steady-state theory which was well-known, a talk that I’ve often heard referred to since.
Weart:We’ll have to come back to that.
Gold:Yes, we’ll get back to that. Then, other outside activities, I’ll tell you about — I was the person instrumental (the only sort of vigorous organizational thing I did), I was the chief organizer of the attempt to get Jawaharlal Nehru elected chancellor of Cambridge.
Weart:I didn’t know about that.
Gold:The official candidate was Lord Tedder, from the glory of dropping bombs. I wasn’t satisfied that that was credentials for a university chancellor. He didn’t have anything to do, it’s only a figurehead anyway, but even at that, it wasn’t my idea to put a military man in charge of a great university. And of course, a lot of the young people in my generation — I had a fairly good sort of position, I was listened to. I was among the younger generation of vigorous young people; I had a good following. So when I found there were lots of people who thought likewise, I organized a very substantial campaign. If you wanted to read that, I have some 35 pages of typescript describing that whole thing. It’s in my drawer here.
Weart:I’d like to have a copy of that. I won’t have a chance to read it now.
Gold:All right, make a note — the Nehru campaign file. I have xeroxed it once before; I can xerox it again. I wanted to publish it once, but I sent it to the Cambridge University Presses and they didn’t want to publish it.
Weart:OK, very good. One other question about the Cambridge period: did you get all your interactions there, or did you also spend an extended period of time elsewhere, during the late forties?
Gold:No; all in Cambridge.
Weart:You must have gone to some conferences and so forth?
Gold:Very little. It was very difficult still in those days to get any money for traveling. I went traveling in ‘47 and ‘48, in the winter — I went skiing in Switzerland.
Weart:I see. No memorable conferences.
Weart:I wanted to ask you, before we go on to other things — you married Merle Eleanor Tuberg in 1947?
Gold:Yes, who was in fact an astronomer, a very theoretical astronomer, having got her PhD from Chicago under Chandrasekhar. She had been a good graduate student under Chandrasekhar.
Weart:I see. Was she British?
Weart:But you met her in Cambridge?
Gold:Yes. She had come to Cambridge on some fairly good fellowship (I forget what it was called), in order to study there with Hartree, who was doing work along the same lines, atomic spectral calculations.
Weart:I see. Has she maintained a separate career?
Gold:No, in fact, not at all. I don’t wish to sound hard about her, but not even to the extent of keeping up with general knowledge in the field.
Weart:I see. So you didn’t discuss these things with her too much then your various ideas and so on?
Gold:I didn’t no. In fact, she was a disappointment to me in that regard, that she wouldn’t even follow my work, or wouldn’t even know what it was all about.
Weart:I see; that’s remarkable in a way, since she had been in astronomy to begin with —
Weart:How do you think the fact that you are a scientist has affected your marriage, your children?
Gold:Well, I’m divorced from her.
Weart:When was that, by the way?
Gold:That was about seven years ago. There is always the question about people who are emotionally more committed to their work — you know, if you are a bank clerk or something and you go nine to five, and you have no interest in your work, no doubt this is a little easier on your family than if you have an intense interest in your work. I traveled a fair amount, but I was also at home quite a fair amount. I wasn’t exceedingly distant or anything.
Weart:The fact that you were a scientist in particular, rather than in some other field of equal —?
Gold:Oh, I don’t know. The children say to themselves (they have been primed by now in that sort of story) that they don’t want to do anything in the same line as Daddy has done, or something. That’s the sort of thing that’s put into their mouths nowadays, I think. People saying, “You don’t want to —.”All this half-baked psychology that the children are confronted with everywhere now, it’s a disaster. But I don’t know, I don’t think there’s much to it.
Weart:Your present wife works over here? (Pointing to outer office)
Weart:As a secretary or assistant?
Gold:Yes, she works here. Three-quarters of the time or something like that.
Weart:Since we’re talking about that, how did you meet her?
Gold:Here, as my secretary.
Weart:I see, OK. Well, now I suppose comes the steady-state story.
Gold:All right. Didn’t I discuss that briefly with you?
Weart:No, we hadn’t gotten into that.
Gold:All right, sorry.
Weart:In the Timothy Ferris book, he tells a story which he must have gotten from you, how you hit on the idea, possibly inspired by a movie that began and ended with the same scene.
Gold:That’s right. Carl Sagan told me that same thing recently, and I recall that I’ve said that. It’s just that I remember that at some time, it may have been at the time I invented the notion, but at some time or other I said, “In a way, it’s just like DEAD OF NIGHT,” which is the name of that movie, where you can come in at any time and you’ll see a complete cycle; do you know the movie?
Weart:No. I understand that it’s circular.
Gold:It’s completely circular. You can come in any time and see it until the place where you came in, it’s all right.
Weart:Before this, had you had any acquaintance with the idea, “the eternal return,” the circular universe?
Gold:No. No, at that time one had not discussed periodic universes either, you see.
Weart:Yes, I know. The steady state in fact does not recur.
Gold:No, no. The DEAD OF NIGHT story is not all that good, in fact. Still, I remember saying it; but how good an analogy it is, is doubtful. What happened was that there was a period when Hoyle and I would sit around in Bondi’s rooms in college a substantial amount of the time and discuss, as Hoyle always insisted, what does the Hubble thing really mean? It was all this obvious kind of discussion, what does it mean, all those galaxies, all this flying apart, would the space be terribly empty afterwards? Has it been very dense in the past? How dense could it have been in the past? Well, it turns out, it can’t have been all that much denser, because the galaxies would then be already running into each other, you see. And could those galaxies form in the expanding thing? And we thought, on the whole, not. I still think not, as a matter of fact. I don’t think that the Big Bang universe, as it’s now discussed, is at all correct in accounting for the condensations. I think that’s an enormous difficulty. But in any case, a momentary situation — I remember taking quite seriously the Eddington numbers, the number coincidences, and saying, “In any of the changing universes you would have to suppose that these numbers were momentary coincidences. Isn’t that sort of funny?” I don’t know how good the coincidences are; I probably thought too highly of the coincidences, more than they’re worth in actual fact.
Weart:These are also Dirac’s large numbers?
Gold:Yes. Eddington was the one who threw them up in the first place, and said, “Isn’t it funny that the ratio of gravitation to electromagnetism is the same as the ratio e2/mc2, the size of the electron, to the size of the universe?”
Weart:Right. By the way, were you familiar then with Eddington’s Fundamental Theory?
Gold:Yes. I wouldn’t claim that I understood too much of it, but I knew it existed and had read at least some parts of it.
Weart:It was published just about that time, I guess. It wasn’t really —
Gold:I even knew Eddington personally at that time.
Weart:You would discuss some of these things with him?
Gold:No, I was too junior at that time to have dared to do that. I had gone to see Eddington because when I was already released from internment, I went to see Eddington to get him to assist in getting Bondi released, which he did. I don’t know what it was worth but at any rate he wrote some letters. He knew Bondi. I won’t swear when I started to read some part of Fundamental Theory, but at that time I don’t think I would have understood all that much of it. So that was the milieu of discussion: what does it mean, the galaxies going apart, and these numbers of Eddington, are they just fleeting things? With that discussion drummed into my ears day after day, I just one day turned up and said, first to Bondi, “Everyone else has to suppose that the matter was created at one moment in the past,” because it was the obvious thing to say. There had been the Gamow discussion, but he wasn’t awfully good — in fact, frankly, between you and me, it wasn’t an awfully tight discussion. One didn’t take it very seriously. But it was the obvious thing to say, that if you see the things flying apart, you can work out when it was together. I said, “People say it was all done all at once. I don’t see why you shouldn’t think that it’s all done all the time, and then none of these problems about fleeting moments arise. It can be just in a steady state” (I really said that) “with the expansion taking things apart as fast as new matter comes into being and condenses into new galaxies.”
Weart:Can you recall how this idea came? It’s a new way of looking at things.
Gold:I know, people have asked me exactly that before, but I don’t know. I would have to duck out the same way as most people who, if I may say so myself, are regarded as inventive and generate new ideas, would duck out. By saying, it’s in some way not in their conscious mind that the searching is done. Ideas are fed into the conscious part of my brain, that I wash my hands of. I mean —
Weart:— it’s just there.
Gold:It’s just there.
Weart:Does it surprise you when it comes there?
Gold:Yes, it sometimes does. I’ll even tell you one occasion where it woke me up in the middle of the night, to the extent of making me write the thing down — and I’m damn sure that it was the idea that woke me up. It wasn’t that I was wakened up otherwise; it was the idea that woke me up.
Weart:Which idea was that?
Gold:That was that spinning dust could polarize light, which is a sort of difficult thing — I’ll tell you that later when we come to it. I often have that feeling. Some new idea suddenly hits me. The only connection I can tell you is that it’s invariably something about which I had previously thought intensely, but which I may (or may not) have brushed out of my consciousness for some time. Therefore, I’m convinced that the structure of a brain is a huge amount of lower orders, as it were, who do an enormous amount of homework all the time, thrashing away at things that they’ve been instructed to do — most of it never sees the light of day — and there is a little bit of conscious single channel working. There has to be a single channel because it has to be the decision-making thing, and decision-making has to be single channel. But the rest is all parallel working in the brain, of course, because the brain’s so slow — compared with computers you have to understand that there has to be enormous parallelism. And then it has to go through a single channel for decision-making, and that’s what we call consciousness. I don’t understand what the meaning of consciousness is, but at least the single channel I understand, that’s how you’d have to design it. If you had a slow computer that had to make decisions, you’d have to make a lot of parallel working, and then a single channel. Then you’d have the problem of access to that single channel. So there’s a sort of Haldeman at the door — I hope he’s more honest — and that is where the individual lower orders, as I call them, try to gain access. They present Haldeman with some importance, you see, “Here we have something that really matters,” and try to persuade him of it. All this is still subconscious. Then finally he says, “Yes, this is important enough,” and he opens the door.
Weart:Have you any idea why — it seems to me that your “Haldeman” lets through more ideas than —
Gold:Maybe the lower orders work better.
Gold:Yes. I tend to think that this is so.
Weart:Rather than a matter of access to your consciousness?
Gold:I think so, yes. I think that the difference between people is very much in how much they maintain the high level of activity in this supply structure, in this homework structure — how much a high level of activity is maintained there at all times.
Weart:Well, do you have any idea why you maintain a high level, or how?
Gold:That’s probably something to do with one’s attitude. It’s probably largely genetic anyway, but what is not genetic — or maybe indirectly genetic also — is the ambition, desire to succeed, desire to be on top and so on. If that’s at a fairly early developing stage in life, you probably get the whole system keyed up that way, I would think. But I don’t really understand it.
Weart:I have some questions then about what your lower orders may have known. What was your knowledge of and your attitude towards Mime’s kinematic relativity?
Gold:Yes. I knew it, more or less; I disliked it, on the whole. Bondi had studied it fairly carefully and had sort of interpreted it to me. I disliked the two time scales situation and thought, all the time, that surely I would be able to hit on some piece of observational evidence that would defeat the two time scales.
Weart:Either geological or astronomical, you mean?
Weart:On one side or the other?
Gold:I just didn’t believe in the two time scales.
Weart:What about other cosmological theories, any of the more far out cosmological theories?
Gold:Well, I knew the existence — I won’t say that I understood them terribly well, but I knew the basic ideas — of the Eddington and the Einstein discussions of whether you could have a stable and stationary universe or you couldn’t, and the cosmological constant, and all that kind of stuff.
Weart:How much general relativity theory did you know? Had you ever read up on it?
Gold:Yes. I would say that I am not competent in the mathematics of general relativity. I still am not, to this day. On the other hand, I probably have a quite good understanding of the logical basis of relativity theory. I’ve since then often lectured on just that, the sequence of logical steps that took Einstein in that direction. For example, I think I contributed quite a lot to Dennis Sciama’s education in this field (which he freely acknowledges; for example, in his book on the physical basis of general relativity I am amply acknowledged for just that). I think I frequently gave quite good lectures on this subject, as to why you must have a curved space and so on. So that much I understood. Altogether, I would say that in the way in which physical science logically fitted together, I was a fairly senior partner among the three. They would carefully listen to me. I’d learnt a lot from Bondi, but even Bondi would listen quite well to it. Hoyle is not a very good listener generally, but even so they would listen to me in any of the discussions of logical interrelationships between branches of physical theory.
Weart:At that time did you know about Jordan’s cosmology?
Gold:And von Weizsacker and so on, yes, we knew about their existence. I don’t think I knew too much about Jordan’s.
Weart:The idea of matter pouring out from centers?
Gold:I know now of course. I don’t think I knew it then. I don’t know whether at that time Ambartsumian had already discussed this stuff.
Weart:I believe that was later.
Gold:That was later. It wasn’t very much later. I think I first heard of Ambartsumian’s discussion only some years later.
Weart:Jordan, you may have heard of in passing.
Gold:Jordan I may have heard of — yes, I knew of Jordan. But I must admit that I had regarded Jordan and von Weizsacker as not terribly serious characters in science. That was incorrect, as I only later understood, but the few ideas of theirs that I’d come across, I tended to brush aside. Of von Weizsacker, all I really knew was his eddies to make the solar system, and that I didn’t like. That’s obviously wrong, it really is wrong; I understood at the time why it was wrong and I was right. Somehow, Jordan and von Weizsacker I sort of brushed aside as not very serious, but that’s incorrect, because in other areas they’ve contributed significantly.
Weart:This is sort of the scientific content now. I wonder also why a theory arises with a particular person — whether, with you or with Bondi or Hoyle, there may have been any personal feelings involved.
Gold:Well, it was like this — that Bondi would always try to further my thoughts. He would always be entirely positive if I said anything. Even when I said something that was wrong, he would try and pursue it as far as he could until it was absolutely clear it was wrong, and then he would tell me. But he would always initially have a very positive attitude, because I had said a few things that had startled him for being right and significant. He knew that I was much less proficient than he in the working out of scientific problems. But he always had a high regard for my inspiration and always wanted to work with me for that reason. We even wrote some papers together, where by all rights he should have been so much the senior partner that my name might have had no business to be on it. But I, in fact, had sort of pushed him to do it, and educated him on the main reason for doing it and so on. So when I first proposed this notion, in the first place he was a little bemused, and said, “It’s a cute idea,” that type of thing. “Obviously it will have lots of pitfalls that we will surely come across very soon.” I immediately said, “Well, I understand, the most obvious observational facts — namely that the rate of generation of matter is so little that you wouldn’t have known.” I think I also more or less immediately said, “And so far as conservation of matter is concerned, you can’t tell me that one knows enough to distinguish in the law of conservation of matter between a co-moving conservation law and a fixed-volume conservation law.”
Weart:That came quite quickly.
Gold:Yes. That you couldn’t really have known that difference, it’s so slight on our scale you see, you can’t tell.
Weart:I don’t recall whether that was in your first paper or not, perhaps that came up after criticism. But that was in your head early on?
Gold:Yes, that was an early remark. And so Bondi went away saying, “Well, we’ll soon find the pitfalls.” And after a week or maybe a bit more, two or three weeks, I kept nudging him a little, saying, “Have you done any more on this?” And he said, “No.” “Have you seen anything wrong with it yet?” “No, I haven’t yet.” I said, “Well, why don’t you go and get serious with it?” So then one day he came to me and said, “Yes, I worked out quite a lot about it. It looks fine.” I said, “Very good.” He said, “Yes, I worked out that it must be a de Sitter universe, there’s no other one that fits, and it makes perfectly good sense. It justifies de Sitter’s calculations, because he obtained his metric without any matter in the universe, but now in this situation we can have a sensible universe.” He was very happy about that. At that stage, almost the same day, I would say, Hoyle came and said, “Tommy, can we write a paper together on this subject?” I’m saying these things very carefully here, because I don’t want to step on either Hoyle’s or Bondi’s toes in any way, but I don’t think I will because this is absolutely accurate. Hoyle came to me at the same time and said, “Can we write a paper together? I’ve had some ideas of how to make a go of your notion.”
Weart:He had been involved —
Gold:He’d been told the same thing, but had not taken it at all to heart to start with. Bondi had much more. Then Bondi had tried to tell Hoyle, “Well, maybe you’d better start thinking about that.” So Hoyle was definitely nudged in that direction in the first place, but then he came to me and said, “I want to write a paper together with you.” I said, “Well, what have you done?” He said, “Your idea really won’t cut much ice unless you can put it into a proper mathematical form, and I’ve invented this particular mathematical form — the C-field — which makes it an acceptable thing.” I listened to all this, and I said to him, “I’ve already persuaded Bondi that the idea is a good one on a very different basis, very much more a basis of general principles rather than of a particular addition to Einstein’s equations, which is what you (Hoyle) are doing. I think I’d better stick to writing a paper with Bondi, because all that I really ought to be concerned with is the generalities of such a thing. And whether the particular C-field turns out in the end to be the only possible way of making something out of this idea or not, I can’t really tell at the moment. I don’t wish to commit myself to such a highly particular application.”
Weart:Hoyle had added one more idea.
Gold:Yes, and it was very specific, you see. I felt I wanted to write a much more general paper, to leave it free for other people to invent other particular solutions. So I respectfully declined to write a paper with him, and in turn started to write the paper with Bondi. We wrote then this joint paper that no doubt you know.
Weart:I’m curious as to who in fact wrote it.
Gold:I will tell you. A substantial amount of the general statements of it are mine. I can pull a copy out and go through it, if you really want to know.
Weart:All right, that would be interesting.
Gold:Sometimes people ask me. (Getting a copy from file)
Weart:I’m particularly interested in the phrase, “Perfect Cosmological Principle”; where did that come from?
Gold:Mine. In fact, I persuaded Bondi to accept that. First he was unhappy about it; he thought that was presumptuous of me, to call something “perfect.” I discussed it for some days. I said, “We ought to have a name for the extension of the cosmological principle that we are giving there. What can we say to make it more so?” I mean more than just the uniformity in space. I said, “Perfect is the only thing we can do because the word perfect, in any case, has a connotation of a temporal kind in our language.” Where did I get that idea from? Parfait? The past tense or something.
Weart:Oh, the “past perfect.”
Gold:Yes. Somehow I liked that. In any case I said, “That’s the only phrase we can invent,” and I persuaded Bondi to accept it. (Looking at paper) The leading sentence is Bondi’s. He’d said that many times before, “The unrestricted repeatability of all experiments is the fundamental axiom of physical science.” But then most of the discussion that follows that is my actual words. The “accidental and inherent” and all that kind of thing, those are my words. Of the first few pages of it, we had both made drafts and interchanged phrases and paragraphs a bit, but I would say that up to the discussion of the observational tests substantially more than half is mine.
Weart:What about this business about Mach’s Principle?
Gold:Again, Bondi had been the one who had, in the first place, taught me to take Mach’s Principle very seriously. But then the actual discussion of it in here is again worded, at least, by me.
Gold:But you know, so much of my education in this originally derived from Bondi — of course I’d added to it by then — so I must make clear that there’s quite a bit that is basically his.
Weart:One more question. This is a different sort of question, about your unconscious minions.
Weart:Of course they have scientific ideas but presumably they also have feelings about things, and I wonder if you know, either in your case or Bondi’s, whether there are any feelings about things like the heat death, the plausibility or significance of the Big Bang, that sort of thing?
Gold:Well, we had a pretty strong sort of emotional bias in favor of the Steady State, once it was pronounced, from the point of view that any finite universe just seemed a most unsatisfactory concept. That in an infinite possible time we were there, we existed on the scene in some specific moment, somehow seemed to us a most unsatisfactory concept. But I discussed it immediately, always, only from the operational point of view. I didn’t allow these sentimentalities at least to get into any writings, but discussed it from the operational point of view. (Looking at paper)
Weart:I think you’ve given me a fair enough picture of the paper. Did you discuss with Bondi or with Hoyle any of these — this is early, before all the debates and so forth started —
Gold:Yes, I’ll come back to that point. What I meant by the operational point of view is this. To make a consistent structure of physical laws — we make a great deal of that in the paper, and that was a major point in my own contribution to it — it seemed to us that you could not reasonably consider that the physical laws were independent entities, independent of the structure of the universe. And if they were not independent of the structure of the universe, then in a changing universe, they would not be unchanging. The major physical constants, or the laws, or any combination thereof, would then be changing. And if they were changing, then we thought that our chances of understanding any cosmology were pretty slim (since one could not experiment with the way in which the laws would change as a consequence of a change of structure). That’s why we would center our interest on a cosmological theory which, if it were true, would be one in which one could discover a lot.
Weart:OK, that’s even stated in one of the papers, yes.
Gold:Yes, that’s the sort of above-board sentiment that you may have, you see. The other stuff is probably not to be taken too seriously, whether you favor one outlook or another on some sort of intuitive grounds. I don’t know what that means. But this is something you can clearly communicate with other people about. I think we say that in the paper: We don’t know whether it’s right, but at least this is the one way in which you could make a lot of progress.
Weart:But don’t the sentiments sometimes play a role, particularly when things come to a debate, in who settles on which side and so forth?
Gold:Yes, they probably do. But you won’t persuade anybody with your deep sentiments, but you will with arguments like that.
Weart:With whom else did you discuss this theory, prior to publication? You mentioned a talk at the Del Squared V Club — was that still prior to publication —?
Gold:No, I think probably not. I think that what happened was the following: I wrote the paper with Bondi. Hoyle wrote the paper by himself. Hoyle showed us his paper (as you can see from our paper) and we assumed of course, that his would be published first, just because he’d submitted it first.
Weart:You didn’t mind?
Gold:Not for any priority reason. I did mind a little, as a matter of fact. But I had declined writing it with him, so I’d not a leg to stand on, you see. He’d given me the option to have my name on his paper. So then it was my fault that I’d taken longer with Bondi to write this paper and he’d submitted his. I felt that I didn’t have any official complaint to make. It did hurt me a little, the thought that his paper would appear first. But it was my fault. We, in fact, comment on Hoyle’s notion, somewhere in the back of this (paper). However, as chance would have it this paper (of Bondi and Gold) was accepted by the referees without a comma being changed.
Weart:I see. No comments from the referees?
Gold:Absolutely: “publish immediately.” And Hoyle’s paper was fought about, and so it was delayed. It appeared an issue later than ours. That’s what happened.
Weart:So he had an earlier submission date, and a later publication date.
Gold:Yes, that’s right.
Weart:Did you discuss it with anyone else?
Gold:I think we didn’t. I think what happened was, we saved this for the Edinburgh meeting of the Royal Astronomical Society, where all three of us spoke on this.
Weart:What was your reception?
Gold:For the most part intense, but negative. I was quite pleased by the intensity. People obviously thought this was an important thing. “Can’t possibly be true, but we’re all shaken” kind of thing. That was the sort of feeling. There was an impassioned speech by Max Born against it. A few of the people of consequence mostly said negative things. Nevertheless, I was really very pleased. I’d given a good presentation in the first place, and it’s quite clear that everyone in the room was mesmerized by the discussion. It was quite clear it was the event; there was no doubt. And that was really as much as I’d expected to achieve. It was a little while after that that I gave a talk at the Del Squared V on the subject and that is the talk which Watson mentions in his book —
Weart:— which book?
Gold:THE DOUBLE HELIX.
Weart:Oh, I didn’t realize; I don’t recall his mentioning it there.
Gold:Yes. He says that after coming from a Del Squared V meeting, at which he heard Tommy Gold speak on the perfect cosmological principle, he went home with Crick and asked him on the way home, “Why can’t we think of anything that is as elegantly perfect (or something) as that in our field?” And he said, in some way that I don’t understand, that this really led them to search for more elegant and perfect solutions.
Weart:What sort of response did you receive from the astronomers around Cambridge, or the physicists, for that matter?
Gold:Well, as I say, we didn’t have much to do with the official astronomers, and they were very much more down-to-earth on details of certain stellar spectra or something, and they really had nothing to do with any of that. None of them discussed any of this with us or had any interest in that discussion at all. With the radio astronomers, there was a background of being on slightly bad terms, as you’ve no doubt read in Edge’s book.
Weart:That came a little later.
Gold:Yes, for the most part, but it probably was already a little bit there, then. At Del Squared V the talk was very well received, and there was obviously a great deal of excitement at that time.
Weart:By the way, in your paper you concluded saying that you hoped to present soon a field theory formulation.
Gold:Yes, because Bondi had said that he thought he could. And then he couldn’t.
Weart:I see. That’s very simple.
Gold:Yes. He had some notions of how he was going to go about it, and then it failed.
Weart:OK. I am interested in a longer thing about the school at that time. You say there was nobody else there who was interested in it among the astronomers, but there did build up the Cambridge school of cosmology. In fact, it’s probably the only school of cosmology —
Gold:— not among the astronomers.
Weart:No, but among the physicists. I think it’s the only place you can ever point to that had more than one or two cosmologists in one place at one time.
Weart:I’m curious, if you could comment on that.
Gold:In this in-between period, just before the publication of Hoyle’s and Bondi’s and my papers, but after their submission — or even before we wrote the papers, but only just before — I remember that Hoyle said to Lyttleton, as we were walking along (I was walking behind them and I heard Hoyle), when Lyttleton asked something about what can be done to solve the cosmological problem, Hoyle said, “You know, there is really only one possible solution, and that’s Tommy Gold’s.” I remember that very distinctly, because it made clear to me at that time, at least, it was fully attributed to me by Hoyle.
Weart:Do you recall how Lyttleton felt about it?
Gold:I don’t think that he was very much concerned in the cosmological problem. He was just interested as an observer, but I don’t think he had anything to do with it.
Weart:OK. Well, tell me then about the general character of response over the next few years. How much hostility did you encounter? How much interest? How much indifference?
Gold:The next thing that happened was that William (Bill) McCrae, who was one of the senior theoreticians in the field, became very enthusiastic about the Steady State theory and wrote many articles about it, some popular articles and some serious articles. That, of course, helped it greatly, because he was sort of senior person in the RAS (Royal Astronomical Society). So with that, we were definitely on the map, at that stage.
Weart:There was this address by Professor Dingle to the RAS in 1953, and I wondered what your reaction was.
Gold:He ridiculed it or something, didn’t he?
Weart:He attacked it.
Gold:I can’t remember. I couldn’t bring myself ever to take Dingle seriously, to be quite honest. I don’t mind that being on the tape, either. He was the president of the Society at the time, I suppose, and so had some influence, but he so misunderstood even special relativity, and fought so vehemently about it. We ridiculed him. I mean, we just didn’t take him seriously in the least. I vaguely remember that he attacked it, but it was only gibberish so far as I was concerned.
Weart:There was a lot of stuff about it in popular journalism, of course, and then there were claims of some people, some Soviets, that Steady State was particularly compatible with Marxism, and Pope Pius came out for the Big Bang — how did all this affect you?
Gold:Not at all. I mean, this kind of thing, I regard as absolute rubbish in the first place. I was a little embarrassed at the fact that even McCrae, I suspected of having some religious motivation.
Weart:In what way?
Gold:McCrae’s a religious person, and we thought — I don’t know whether we actually knew, but I think we thought — that he had embraced the Steady State theory because somehow his religious picture fitted that in some way.
Weart:How could that fit?
Gold:I don’t know. In any case, that was his viewpoint. He had a large view, I suppose — he wanted an eternal God, not a temporary one — I don’t know.
Weart:I see, not just one time.
Weart:That’s interesting, because it’s been said that the Steady State theory is overtly anti-theological, or rather anti-Christian.
Gold:Well, the religious people, as we know full well, can make their peace with anything, or make their war with anything. Religion can always be seen in anybody’s mind from a different angle that gives diametrically opposite results. For that reason I don’t take it very seriously.
Weart:What about Bondi and Hoyle, how did they react to these issues?
Gold:Same as I. They’re both quite anti-religious too. As I say, if anything we were a little embarrassed at the thought that Bill McCrae was making propaganda for this on possibly religious grounds.
Weart:But you never saw Steady State itself as being anti-religious?
Weart:You see religion as being irrelevant in general.
Gold:Quite vehemently. Bondi spent some years, later, being a sort of lecturer of the Rationalist Society in Britain, which is anti-religious. Do you know what the Rationalists are? It’s a quite dignified anti-religious organization, which in Britain can exist. In this country, it wouldn’t be possible, I think.
Weart:It would be difficult. Did you discuss these things, by the way, religious feelings toward Steady State and so on?
Gold:Humorously only. In our in-circle, we wouldn’t bother to speak about it in any way other than in a pretty crass sort of way.
Weart:Now, Edge did interview you about the radio astronomers business?
Weart:So perhaps we shouldn’t go into too much detail about that.
Gold:That’s right, he has most of it. Most of that is correct in his book.
Weart:OK. Why don’t we skip that then, because we don’t have a lot of time?
Weart:I do wonder if there’s anything, any incident or any general thing that was important, that isn’t on the record so to speak, not covered in Edge’s book perhaps.
Gold:About the relation with the radio astronomers?
Weart:Or about the Steady State debates in general, because Edge only covers a certain aspect of it.
Gold:Yes. Well, it was Bondi and I who, to our knowledge, discovered first the fact that the Ryle type of (number-magnitude) plot would, as a consequence of random errors, be steepened.
Weart:I hadn’t realized that.
Gold:That was an important point to realize: if you make random errors, then the curve will become steeper. Scheuer had not thought through this correctly; Ryle had thought that if you make random errors you just make random errors, and intrinsically the random errors must make a random scatter on his plot, But it’s not so. If you have a plot of this nature, an integral plot, and you make random errors, you always — you understand why? You know about the curve...
Weart:— I can easily work it out.
Gold:The situation is this. You’re concerned with a box that’s supposed to correspond to a certain intensity. And you’re making errors in the intensity measurement so some sources will be called too intense and therefore be put in the more intense box, and some will be called too weak and therefore be put into the weaker box. But since there’s always a much larger number in the “lower intensity box” than in the “higher intensity box,” a random error will mean that you will always make a bigger impact on the ones that you have fed to the higher intensity box than the ones you’ve fed to the lower box. That point became first clear to Bondi and me; I won’t assign responsibility between us on this because we just debated it out between us and came to that conclusion. I can’t remember now whether we had a prior publication on that or not. I once searched for it, and I’m not sure what I found — subsequently I found it, I think. But in any case, it was also published by Bolton, and I don’t know who has priority in this. But certainly to us, and to our British circle at that time, there’s no question that we discovered that fact.
Weart:If you had something like this, would you go to Ryle and say, “Now, look here — or?”
Gold:No, we’d publish it. If you had a hard fact like that, you’d publish it.
Weart:You didn’t have much direct contact with him, then.
Gold:No. I do recall this, though. I went into his lab after he’d made the announcement, in the first catalogue that he had shot down the Steady State theory. I remember going to his lab and sitting myself down on a table there. Ryle and two or three other members of his team collected around there, and I said, “How secure are your data? I mean, do you really know?” Hoyle had taken the data very seriously, you see, and I kept saying to Hoyle, “Don’t trust them, there might be lots of errors in this and it can’t be taken seriously.” Hoyle said, “You must take observational data seriously, otherwise you’re nowhere.” I said, “I will take them seriously when I know they’re correct and not before.” So thereupon I walked into Ryle’s lab, just to assure myself, and I said, “How sure are you guys that you’ve really got the thing right?” I said it in quite a pleasant tone, and I was quite well received there, but they were grinning and sort of definitely thinking, you know, they had us by the — whatever. So Ryle said, “We can show you the graphs and the recordings and so on; we’ve taken every possible precaution; and Peter Scheuer (who was not present at the meeting) has worked out that really it doesn’t matter what kind of errors you make.” I said, “Well, how much error in intensity are you allowed to make and how much error in the intensity measurement are you in fact making?” And he said, “Oh, it doesn’t make any difference. Peter Scheuer has shown it wouldn’t make any difference at all.” I said, “If it doesn’t make any difference what intensity you judge a source to be, then why do you have a radio telescope?” Then there was a stunned silence. And it turned out that he’d mistaken the notion that the intrinsic intensity of a source did not matter — but the measurement of course does. Peter Scheuer had correctly seen you can have a random scatter of the intrinsic sources. But if you make an error in measuring them, it does matter of course. Otherwise, you wouldn’t need to measure a darned thing, would you?
Weart:I must say, with all these radio source counts one needs a very logical mind.
Gold:Yes, yes. So when I said, “Then why do you need a radio telescope at all?” there was a stunned silence, because they realized there must be something wrong with what they said. I more or less left them with that conversation.
Weart:By the way, of course Hoyle played an important role in all of this, and I wonder what his character like at the time? I’m particularly interested because, of course, Hoyle became one of the main people to carry on the Steady State theory and continue it.
Weart:Was it something about his character or scientific approach?
Gold:Well, he was always a difficult person, even for us to converse with or to debate anything with. In previous times, that is. It’s not so difficult for me nowadays when he comes and visits me here. Now I have long and useful scientific discussions with him. But in his younger years he was very difficult to talk to, for anybody. He wouldn’t listen. You’d tell him something time and again, some little point on which he was misconceived, and you couldn’t straighten him out at all; it was just infuriating. He just wouldn’t listen and wouldn’t take it in; and then maybe later he’d tumble to it, and then think that it was his own invention. Typically a very independent mind, so independent that you can’t penetrate it at all.
Weart:But you still got on with him.
Gold:Oh yes, on a personal basis we get on very well. But on the other hand, I’m sure he was very abrasive towards many other people, as no doubt I was too. Bondi was the gentle one. Lyttleton, of course, is absolutely hopeless, for abrasiveness. He makes wonderful remarks that are cutting and devastating and very humorous, magnificent wit. Hoyle too is sometimes very witty, but Lyttleton is the severe wit — he’d cut them down. You know some of the remarks? There’s one that became quite famous. On the Council of the Royal Astronomical Society, a paper was being debated — not a particularly interesting paper, just a paper that was being debated whether to accept it or not. There were very conflicting reports from the referees, and Lyttleton said, just sort of in general annoyance with the procedure, “It’s about time we had some competent referees on the job.” The president said, “But Dr. Lyttleton, we sent this paper to the most eminent men in the field,” and Lyttleton’s reply: “I said competent, not eminent.” Any such thing was always instantaneous, on the tip of his tongue.
Weart:There’s a place for that, too. Well, after Steady State, you began to do work in a number of other subjects, but mostly astronomical. Is there still something more to add about Steady State, that first period?
Gold:Well, I wrote a number of minor things about it, explaining what the horizon looks like and things like that.
Weart:These things are available. One can read them. Anything else that might not be on the record?
Gold:I think we published something popular in one of the journals. Now you’re getting me to remember how incomplete my reprints are. Here I have some 210 reprints or something in my files, and every now and again I come across another one that’s not in there. You’ve just evoked another recollection. We wrote a semi-popular article in a glossy scientific journal — was it called ENDEAVOR, or something like that? It was a glossy large- format journal in Britain that was sort of SCIENTIFIC AMERICAN-like. But there existed such a paper, I’m sure, and now I’ve not seen any reprints of it for 30 years or whatever.
Weart:OK. Well, without going into all of these astronomical and planetological things, terrestrial magnetism, galactic dust, and a lot of other things during the next few years — I wonder, did you feel committed to astronomy and planetology? How did you get into doing these things?
Gold:Oh, I just gradually became more proficient at understanding things in astronomy. I did a little work on dynamical problems. Spinning dust was one thing; I told you, I absolutely was awakened in the middle of the night with that notion.
Weart:Did you make any decision, that astronomy or terrestrial physics was the direction you wanted to go?
Gold:Well, by the time I’d got this fellowship in Trinity and written the Steady State paper, I didn’t have any worries about a career or anything, you know. I was obviously in perfect command of the situation. So at that stage, I just did whatever interested me; absolutely blatantly.
Weart:Now, from ‘52 to ‘56, you were chief assistant to the Astronomer — I’m not sure who the Astronomer-Royal was, by the way.
Gold:Sir Harold Spencer-Jones. He was a very nice conservative gentleman who, however, appreciated our group more than you would think. He had to step a little out of line with his cronies in the old establishment, to take a rebel like myself in as chief assistant.
Weart:Was this specifically because of Steady State?
Gold:No. By then we’d worked on a few other things that he understood. He understood dynamics, and I’d done a little bit of dynamics.
Weart:I mean was it specifically because of Steady State that you were regarded as a rebel?
Gold:Yes. I suppose, yes.
Weart:What were your duties? What were your working conditions at the Greenwich Observatory?
Gold:Fine. I was very satisfied with the three years that I was there with Spencer-Jones. He sort of left me alone. I could administer any of the departments I took an interest in — it’s a large place. I didn’t have to. I could share out the administrative work any way I liked. And so in fact, I looked after the solar department quite a bit. I was quite interested in electrodynamic processes on the sun.
Weart:Was this how you became interested in solar work, or were you interested in solar work and therefore took an interest in the department?
Gold:I had become interested in electrodynamic problems before I went to Greenwich. I had already written a little on magnetism before then. At that stage, I’d really learnt electromagnetic theory pretty thoroughly, and I was interested in solar phenomena. I had a very easy time there. I spent a lot of time just writing papers. I wrote the long moon paper there, the one on the surface of the moon. And I wrote the dynamics of the earth’s rotation.
Weart:I wanted to ask you about both of those papers, and to take them in order. Actually there’s one here I wanted to ask you about even before that time. I think it was 1951 at this London Conference, the paper on cosmic rays and the origin of radio noise.
Weart:You made a number of contributions — the cosmic rays and the radio noise, the distance of radio sources —
Gold:That the sources were distant; and that if they were radio stars, they would be small condensed objects with strong magnetic fields, and they would have time fluctuations in their signals that would be very rapid, with a time scale of the size given.
Weart:Can you say how all these ideas came together?
Weart:This was part of the debate with Ryle, I gather?
Gold:No, this was in the prepared paper I’d written, I suppose only just shortly before the conference. I knew I was going to this conference and I’d collected my thoughts on the origin of radio noise. I had known Ryle’s position: that there were radio stars, like other stars but invisible, but on a distance scale of other stars. I’d already known that I was going to confront the large and already quite powerful group of the radio astronomers there with an opposing viewpoint. And so I tried to marshal as much of my thoughts as I could, and wrote all this in there. I must say that it was only quite recently, long after the pulsar story — the pulsar story is after all only ten years old now — it was only within the last two years or so that I again stumbled on this thing, pulled it out of my files, and found the remark in it about small condensed objects with strong magnetic fields. I never remembered that I’d published that anywhere. But I obviously had that thought in my mind from then, long ago. So then when the pulsars were discovered, those lower orders that I speak about were quite aware of that whole story at that stage, you see.
Weart:They went to their files or whatever.
Gold:Yes. That’s right.
Weart:One of the things that I was struck by was this argument that the steadiness of the sources as they were known then argued against their being collapsed stars, because the fluctuations would be rapid. I wondered, was this sort of time-of-flight argument common background thinking then, or did it strike you as a new approach?
Gold:It struck me as new.
Weart:Did you recognize at the time it was new?
Gold:No, I suppose I must say it wasn’t all completely new. I had thought about this in relation to solar outbursts.
Weart:Oh, that’s interesting. That’s where it comes from.
Weart:The sharpness of the rise and so forth.
Gold:Yes. Some solar outbursts were already known at that time that got into the ball park that you had to think that the source had to be small.
Weart:I see. I suppose this was also related to your thinking that it would have to be a small magnetic object, to give out radio waves.
Gold:Well, what I say there is more or less exactly what I thought. You see, one didn’t understand how to emit radio waves at all well, in those days. I had an outlook at the time that you had to do something similar to what any kind of a transmitter tube does. How would you do it technologically? That was about as much as I understood, you see. I understood a lot of transmitter tubes, because I in fact, had worked on them, as you know. So I knew all the different designs of crossed fields and this and that, and so I thought in terms of what kind of a system would a transmitter tube be? Well, it does it by exciting a bunch of electrons in coherence, and in general it means that you must not have a conducting medium all over the place, because you can never put any energy into electrons if you have a general conducting medium. You see all the electrons move very slowly and make a huge current and nothing gets a big amount of kinetic energy into it. So I thought, well, it will only be in the presence of strong magnetic fields that you cannot conduct electrons across field lines; it’s only in those circumstances that you can get a lot of kinetic energy into electrons. You can make big electric fields and then you can do something with that. In other words, the insulator that you would have in a vacuum tube did not exist in space. You’d have a glass envelope or this or that, an insulator, but you don’t have that in space. And on a large scale I understood that even very tenuous plasmas are very conductive; that much I had known. So I said, the only way in which you could have any strong electromagnetic effects is by having sufficiently strong magnetic fields so that they stop the conduction currents. Then I said: how do you get very strong fields that can do that? Only by having a collapsed object, which has crowded in a lot of field by the collapse, but allowed some of the field to stick up where the space is low density. Only by the juxtaposition of a very dense matter with empty space. An ordinary star can’t do very much of that, because it has a very gradual atmosphere so the conductivity fades away. Therefore, I said it must be a very collapsed dense object, so that the field sticks out, is very strong but in a very empty space.
Weart:Let me ask you about quite a different field. That’s the instability of the earth’s axis of rotation, arguing that the pole hunts under some conditions. How did you come to look at that problem? That’s a totally different sort of a problem.
Gold:Yes. I had thought a little about the inside of the earth. So had Bondi in a totally different context, but I suppose I had discussed a little with him. He had thought about some hydro dynamical problems on the inside of the earth.
Weart:That’s right, and you’d written a little bit about the magnetic field.
Gold:And I’d written a bit about the field — I’m not sure, was that before or after? Also, I’d worked on the damping; with Bondi I wrote a paper on the damping of the nutation of the earth.
Weart:I see. So it comes from that direction.
Gold:I’m not sure which paper was written first, but that doesn’t matter, because the work was certainly at much the same time.
Weart:I wondered if it had any relation to the work at the Greenwich Observatory.
Gold:No. What had happened there was that I had read, just to educate myself, Harold Jeffreys’ book, THE EARTH, the early edition whatever it was, and had burst out laughing at one point. A fair amount of my scientific ideas are as a result of criticism, of seeing something wrong. I’m quite often jogged into thinking by finding an error. Even now, the present earthquake stuff is much of that kind. I read through Harold Jeffreys’ book, and when he comes to discuss the damping of the nutation of the earth, he has a formula in there about the viscosity that’s needed inside to cause the observed damping. Because you see that it’s swinging around a little bit, and then you see it settle back. He had a formula in there, and I said to Bondi, “Ha-ha, look at that nonsense that Harold has written there. If you stick in something the size of a pea in the middle of the earth, and adjust the value of the viscosity right, you’re going to get the damping out of it.” I said, “I’m damn sure that a thing the size of a pea couldn’t damp the earth, whatever viscosity you put in there.” Bondi looked at it and roared with laughter too. This had been in print for some time then, innumerable geophysicists had studied the matter. So then we wrote a paper putting it right. It was just a goof on Jeffreys’ part. Harold Jeffreys unfortunately debated the paper hotly in refereeing, before admitting to it. Eventually he did. But first, he wanted to throw it out — even though it was so blatantly clear. That was one thing where I was just reading to educate myself, and coming across a mistake, and tidying it up.
Weart:Then you had to find, how it does work.
Gold:We had to find how it does work. Then we made the correct theory of the damping of the nutation of the earth, which is what we did.
Weart:And then from that, you got to the question of —
Gold:— that’s right. Then I thought about the polar wander. I thought about that a little bit more deeply, and I read what Kelvin had said about it. Kelvin is very misleading. Kelvin had first said something sensible about it, then had worked on it, had done the wrong thing, an error, and on the basis of that retracted his earlier statements and said, “No, now it is absolutely clear, it’s proven that the axial rotation of the earth is perfectly stable, can never take another position.” That was his final conclusion. I read George Darwin and his conversation with Kelvin, I suppose it is, or his debate, but at any rate, Darwin and Kelvin both thought that it was stable. But within the same set of assumptions, I could clearly demonstrate that it was not so. They were prepared to think of a pliable earth, you see. But they had not understood the only point in my paper really that counts: I understood that the adjustment by the pliability of the earth to a new axis is never final. That was the point that they had mistaken. They had thought that if you put a slightly off-center weight on it, it will merely adjust itself and the pliability will adjust to that new situation. But that’s not right. What happens is that if you put an off-center weight there, it will only be stable when it’s shifted all the way around, until that off-center weight is on the equator. Not before. That’s where they were mistaken, you see, they had just not thought out correctly around which axis it will stabilize itself; there are three axes involved that you have to discuss. They’d made sort of a little bit of mental confusion about it. I felt good about having corrected Kelvin about something. Kelvin on the whole had been very correct. He may have had wrong opinions, but to have claimed to have shown something mathematically, you see —
Weart:It was a feather in your cap.
Gold:Yes, that’s right. I was very pleased with that. So I wrote that paper, and had very little response to it. Except that then very nicely Walter Munk picked it up, and wrote an erudite paper on “Polar Wandering: A Marathon of Errors,” in which he gives me full credit for having solved the problem that Kelvin had gotten wrong.”
Weart:Geologists in those days didn’t like to think about things wandering around quite so much.
Gold:That’s right. And what I say in that article is something that I still insist to this day — that if you have an earth which is pliable enough to shift the direction of the poles; it has to have some softness to do that. But then if it has a bulge, in any case that bulge is due to its softness anyway, so I assume that it has it. And if it has that kind of softness, then the pole can wander. But if it is to allow an independent movement of plates, of continents, that implies a much greater degree of softness somewhere. So therefore, the correct mental attitude to have to that problem is, you must always try to ascribe any data that you have first to polar wander, and only what’s left over to an independent movement of the plates. Because it could be that only the pole could wander, the plates could not move at all — but it cannot be the other way around.
Weart:Right. To turn to another paper of the same year, the prediction that the lunar surface would be powdery — indeed that the maria might be pools of powder.”
Weart:How did you get into this problem? Tell me about that. That’s a deep problem, if I may say so.
Gold:Well, why did I start to think about the moon? I just looked at the darn moon, and I looked at earth-based pictures of the moon, and said to myself, “Well, it’s quite clear that the craters are different stages of erosion.” People in those days were still debating whether craters were made from volcanoes or impacts.
Weart:You were interested in that problem? Just something that was floating around?
Gold:Well, I was immediately persuaded that explosive events had made the craters, not volcanic, just from their shape. I can’t quite remember when Baldwin’s book came out, whether it was before or after I worked on this; I suppose before. But I really only concerned myself with Baldwin’s book afterwards. (Looking for book on shelves) In any case, there was some support at that stage that it was impacts, and I was surely on that side. But then I saw immediately that you had to say that the old craters were heavily eroded. So I thought, well, I’ll draw myself a few cross-sections, and see what are the heights approximately from shadow measurements? I drew a few cross-sections, and asked how much material is missing from the old craters, all over the highlands. You find that in the same scale on which a young crater — to a certain height scale — would have looked like that. An old crater of the same diameter, when you actually drew the profile, looked like that. Literally, I’m not exaggerating.
Weart:I see, it looked like the same thing only slumped down and filled in.
Gold:But absolutely the merest smidgeon was left over. From plan view you saw it very precisely, as a round crater still. And so I said, “Well, all that stuff is missing.”
Weart:All the stuff that had been in the rim before.
Gold:So I said, “How could all this stuff disappear?” When you draw a few cross-sections like that, you see such an enormous amount that’s missing — a sort of mean, over the highlands, of at least a kilometer is missing. So I said, “Well, where has all that stuff gone? How can you dismantle a wall of a crater kilometers high?”
Weart:I see. You started this because of the volcanism problem, essentially. Started asking about how the profile could change?
Gold:I don’t know; that I can’t tell you. I just looked at this, and immediately, it sort of hit me that obviously a huge amount of erosion had taken place. I drew a few diagrams, and persuaded myself that it was a kilometer at least. And so I said, “Well, a kilometer of stuff must have gone away. I’d better look into what kind of a theory you could have as to where it had gone?” First I thought about whether it could have evaporated from the moon, in some way — left the moon altogether in some way. I concluded, after thinking about methods for removing stuff, that no, I couldn’t see any way in which it could sensibly have gone away. So I said, “Well, it must be that all that stuff that’s no longer in all the innumerable mountain rims must have concentrated itself in the low spots. There must have been some way in which it could have walked. And if it could have walked, well, it certainly couldn’t have walked as big chunks.” I didn’t see any evidence of any major flows of anything that could have moved big boulders.
Gold:So I thought: the only way in which I could have transported these huge amounts was by supposing that, when I see the little leftover rims, all that remaining material has gone and filled in all the low spots. And that, I’m sure, is the right theory. I will insist that that’s the correct theory. And since you’re recording this for posterity, that’s how it will one day be known. But boy, the nonsense that’s being talked about that now. And this very simple argument is still as strong as it ever was. In all this modern discussion on the subject that has now become fashionable, there’s not a hint of a suggestion as to where they think that all this material is. They have to acknowledge its missing.
Weart:Now tell me, after you came out with this — I don’t remember, I suppose it was a good bit later before the press began to be concerned about this sort of thing —
Gold:I was subjected to very unfortunate publicity. My story was entirely that the missing material is down there; therefore, it must have been finely divided, it must be a powder. As a powder, I could think that micron-sized particles might have moved, in the long span of geologic time. And I immediately said: either thermally or electrostatically or one thing or another; I gave various possibilities as to why they might have moved on this long time scale. Then the newspaper people did a very unfortunate thing for me. They picked on the aspect that they thought they understood, namely, they thought that if it was a deep deposit of powder, that automatically meant that you would sink in and disappear.
Weart:Was this very soon after your paper came out?
Gold:No, this was only after space flight looked plausible and people got interested. Then Arthur Clarke wrote a book, A FALL OF MOONDUST, which also had it soft, Arthur Clarke said to me that he feels that he owes me a lot of money (I said, “Well, why don’t you give it to me?”) — because it was my idea that had made him the biggest sum of money from books. That was a great disservice to me because I frequently said — and I always said very carefully, right from the start —“In a vacuum, a powder will probably cake quite well, be quite firm.” I discussed it as a crunchy substance, or like a cake. “But,” I said, “on the other hand, it is a terrain that has never been subjected to wind and water, like terrain on the earth.” The kind of examples I gave was “the only case on the earth where you have a terrain that’s not been subjected to much stress of the weather is a glacier after a snowfall, before anything else has happened.” I said, “If you walked on a glacier after a snowfall, you’d want to be on a rope, because you wouldn’t know what the subsurface was like.” That’s the only context in which I said that it might be dangerous. You don’t know: here is material that has been deposited as a fine powder, nobody’s ever stepped on it, and maybe there are some bridges, hollow spaces underneath. I also said, “Maybe some objects that have churned in at a low speed might have made tunnels underneath.” And that’s still true. That may still be the case. The astronauts didn’t fall into a hole, but they might have done — because you would make quite a good tunnel if you shot a boulder of a meter size, under low speed, into the moon. It would go a few meters in and would make a hollow. For many other reasons there might be hollows there that might be bridged over. That’s the only thing that I said. Even to the Apollo people, I always said, “If I went, then certainly for the first little while I would insist on being on a rope.”
Weart:Why did this cause you grief? Because afterwards, people said you were wrong?
Gold:There was an enormous campaign against me afterwards, saying, “Well, you see, Gold was totally wrong — the astronauts did not sink in and disappear.” I had long before then absolutely insisted, that’s not in the least what I was saying. In one paper in SCIENCE, for example, I wrote, “It is quite foolish to think that that material will be extremely soft. What I’m describing is a deposit. If you step out of your plane at Denver, you are stepping on a kilometer of powdery deposit, but you don’t expect to sink a kilometer down when you step out of the plane.” I said exactly those words, you see — several times and in public, and on radio and television and everything else. Nevertheless, time after time, the reporters wrote that “Gold says you’ll sink out of sight.” I couldn’t stop it.
Weart:Even among your scientific colleagues, this idea —
Gold:It became absolutely stuck that I had said you’ll sink out of sight. I’ll show you all the literature on it — I consistently fought it, and told the reporters, “Now, don’t you go away and repeat that same stuff as your comrades keep doing; that’s not what I’m saying.” But that’s the only thing they understood. That was dramatic. When in fact we went to the moon, my feeling was, obviously I was right: the stuff was completely covered with dust. They never found anything that was not dust or a few scattered rocks. But no solid rock, no bedrock, was ever seen, no substance other than scattered rocks and dust.
Weart:Because they didn’t go to the highlands?
Gold:Yes, they did go to the highlands. But everything there is covered. There is no solid that they ever found, even in the highlands.
Gold:No bedrock. Although each mission was geared to searching for bedrock as the main object, no bedrock was found. My view was that it must be pretty far out of sight, because there’s so much stuff that has been shuffled around. Then, a little later — or already at the time I had an inkling of the radar results, already in ‘55. Later, of course, the strength of the radar results became clear to me and that is absolutely devastating. The present fashionable Houston discussion of the moon is just totally irreconcilable with what I regard as the firmest data of all. You look at the radar signal from the moon, at long wavelengths. If here is the limb of the moon, and here I plot intensity of it — here’s the middle of the disk, here, so, here the signal has to go to zero because it’s the limb — then, the low frequency radar looks like that: (drawing)
Weart:So you get a very sharp reflection from the middle.
Gold:An enormous peak. And this curve here is a factor of a thousand down from this peak.
Weart:When you get a little bit towards the limb.
Gold:— a few degrees away. Down a factor of a thousand, so there’s a spicular peak in the middle. Then the diffuse scatter of the moon is 30 db down on that, at 7 meter wavelengths. And the long-wavelength penetration through the powder we know, because we brought a lot of powder back, we can measure it, no question about it — we’ve measured here some 50 samples, and other people have too. It is always extremely low absorption. Those radio waves will look into that powder a distance of at least 100 meters, more like 300 meters, and if there were any rough interface down below that could be reached by that, then that signal would look like this: (drawing)
Weart:It would be very much broader?
Gold:No, the rough scatter would be right up there, only a few db down on the peak. You know, the optical moon is uniformly bright.
Weart:Right, and the radio moon, you see a bright spot.
Gold:At a long wavelength you’d get the additional, spicular thing there, but you can work out how much the rough scatter would be, looking through the first layer of powder, and if that’s thin enough not to absorb, then that would be there.
Weart:You should see a disk with a bright spot in the middle, but instead all you see is the bright spot.
Gold:With a huge margin. I needn’t debate the detail values, because it’s 30 db by which this is in error, a factor of a thousand. Nobody can possibly make any discussion that comes remotely near to solving this problem.
Weart:You feel, because of your press image, now nobody takes your theory seriously?
Gold:The whole geologic fraternity who got into this, being pushed into it by money given out by NASA suddenly for a new subject — NASA had the mistaken view that you should put the whole field in the charge of geologists, let geologists run everything. And so they did. They instructed the astronauts, they did everything, they prepared the experiments — they had started out with the firm notion that the moon was a lava body. When they got there and they found the composition arid the chemistry of the material, it’s a ground-up powder; but they call it a lava,, It’s a mixture of feldspar and pyroxene, the crystals that are there, and you have no right to call that lava — it’s ground-up rock, of mainly two different kinds of minerals. But they call it a lava. The few chunks that you find scattered around, you might call lava. But they are for the most part or all just the consequences of some melting of that same powder. And if any big impacts had happened, they would certainly do that. So I can’t see any sense to that whole story. But they started out “knowing” that the big flat regions were huge lava beds. To start with it was thought that they would be lava and that’s why they were dark, and then they got there and they found that it was dark because the powder lying on top was dark, so they said, well, nevertheless the lava must be right underneath, one centimeter underneath. Surveyor dug in three centimeters, and they said, four centimeters underneath. Then the astronauts go there and they dug around, they eventually dug down 2 1/2 centimeters with a drill, and so the story now is that the bedrock is 3 meters down. But the radar tells me that it is certainly not within the first 100 meters. And the point is now that if it is not within the first 100 meters or anywhere near that — in fact, if it’s not within the first few meters generally — then the chemistry of what you see on the surface of the moon is completely dominated by the in-fall, and not by any ground-up bedrock. If the bedrock is that deep down, then you’ve brought in so much more material that doesn’t do any grinding but merely adds, for so little that will achieve any further grinding, that once you’ve got more than three or four meters of powder, the thing acts essentially only as a collector of the chemistry that’s fallen in from space. The other side know that if the bedrock is not within the first few meters then they’re out of luck, in the sense that all the elaborate stories about the chemistry of the surface and how it was derived, in this location and that, from what flow, from where — that will all evaporate completely. Because in fact that chemistry that we’ll be seeing is the in-fallen chemistry. It makes a complete division between the two viewpoints. Then there’s always the business that people cannot understand that in-fallen chemistry would have a patchwork over the surface. Invariably when I say that (it’s in-fallen) they say, “Oh, but we know that it’s different in one place from another, how can that be?” Of course it’s absolutely obvious how it can be. If you throw in on the moon different stuff in different epochs, if whatever falls from the sky is not exactly the same, it will make a body like an onion. But then of course all the big impacts, which you see have occurred, will dig out a huge amount out of this onion skin affair in one place, and deposit it around it. So now you will always make a regional pattern out of what would have been for fine stuff only a vertical pattern. That’s all you’ve got.
Weart:OK, back to the 1950’s.
Gold:Well, then I got interested in various electromagnetic things.
Weart:Let me ask you first, before you get to the plasmas and so forth — you became a professor of astronomy at Harvard in 1957.
Weart:I wondered about that, why you moved to Harvard.
Gold:Then it was that Spencer-Jones had to retire, and I did not get on with Woolley, his replacement, at all. I regarded Woolley as very boorish in his attitude. You don’t know how correct that word is — boorish because he’s a Boer; that’s where the word comes from, of course. I hadn’t thought of it before, but van der Riet Woolley is his name. So there’s something to it. He had an obsession with his particular branch of astronomy, and everything else was not astronomy. I had built a solar cosmic ray measurement equipment there, of the finest, the world’s best. It had just been constructed when he took over. He said, “We’ll have to remove that. It has nothing to do with astronomy.” Within one month of his taking on the job there was the great solar flare. We were the best recording place as a result of this (apparatus) still working there, before it was taken away. And of course, it was an absolutely enormous success. We had recorded this great natural phenomenon the best of anybody.
Weart:But nevertheless, he —?
Gold:Nevertheless he was going to remove it. That infuriated me.
Weart:Tell me briefly how you went to Harvard. You looked for a job?
Gold:I looked for a job. I was offered a job in Oxford which almost certainly, after a year or two later, would have been a job leading to the chair there. But I looked it over and I wasn’t all that thrilled. Various makeshift arrangements were offered to me, as soon as it was known that I wanted to leave Herstmonceaux. One was between Oxford and Harwell, the atomic energy research place — they were going to make me some joint offer. The other possibility was back to Cambridge; one of the colleges offered me a job. But I wasn’t too thrilled with any of these. I had traveled around the States the year before, and then, absolutely totally out of the blue, I received a telegram from Harvard saying, “We offer you a full professorship at Harvard.”
Weart:I see. No negotiations preceding this?
Gold:Nothing; just a telegram falling into my lap. I thought it was fine. I decided I would go to the States. My wife then was American anyway, and she was quite keen to go back.
Weart:Did you plan to stay here?
Gold:Yes. But I wasn’t sure whether to come to Harvard or Cornell, because Cornell I’d enjoyed more, on the occasion of a brief visit before. I had contact with [Philip] Morrison, who was then here, Salpeter, who’s still here, and Arthur Kantrowitz, who was here then. They tried to make me come to Cornell. But Harvard had made me this superb offer. I decided to take one semester at Cornell and then take on my professorship at Harvard, so as to be able to see both places. I stayed at Harvard then for 2 1/2 years, and decided that I personally preferred Cornell, and by then Cornell had made me the offer of setting up a center, and making me the director of it. As it turned out shortly after that, the going was not really as easy when I came here to Cornell as I had been led to believe. I had some doubts as to whether I’d made the right decision.
Weart:First I’d like to ask a couple of questions about Harvard. Or first, comparing astronomy in the United States with astronomy in Britain as you had seen it, were you struck by any differences?
Gold:Yes, it was better here although Harvard was not all that much in the first rank then, either. But I certainly had more intelligent people interested in the subject to talk to at Harvard than I did at Herstmonceaux. Also, at Harvard I greatly enjoyed the company, and saw a great deal of, a person who’s now a good friend of mine, Ed Purcell. So that was very good.
Weart:Did you see differences in the social structure of astronomy, the way people would talk to one another, get together, that sort of thing?
Gold:I suppose that Harvard was a little bit sticky too. I mean, like Britain is, sort of cliquish and so on but less so. It was not nearly as free a society as, for example, Cornell was.
Weart:You came to Harvard shortly after the fight over the directorship there, after Bok had left?
Gold:I was the replacement for Bok.
Weart:Did that leave any repercussions that might have affected you?
Gold:No, I don’t think so. I was on good terms. It was Donald Menzel who must have been chiefly instrumental in the offer being made to me. But of course, Harvard is very systematic. In fact, there were outside committees and everything else before the final offer was made to me. Menzel must have been instrumental, but I was on very good terms also with Whipple and so on. On the other hand, I didn’t really have all that much scientific contacts with either of them.
Weart:What about when you came here then? You found the department — I guess it had two people in it, J. P. Cox and R. W. Shaw.
Gold:You really researched it — how did you find that out?
Weart:I looked it up in the Cornell catalogs — Shaw was busy teaching celestial mechanics, navigation —
Gold:Yes, it was a terrible situation here. There were just a few undergraduate courses in astronomy, which was a sort of soft option for science, and then a few specialized courses to prospective navigators and so on.
Weart:You were brought in to change this?
Gold:I was brought in to be the new chairman of the department. My first introduction to my new position, from Mr. Shaw, was for him to say, “I’ve got tenure here and you won’t be able to throw me out for another” — whatever it was, ten years, I don’t remember, however many years it was that he had to go. But he immediately said that to me. You can imagine the sentiment of the situation. You come in as the new chairman of the department, and the old boy says to you, “You can’t get rid of me, whatever you do.” Well, it turned out that I couldn’t.
Weart:In fact he did leave fairly soon afterwards, didn’t he?
Gold:No, he stayed until he retired. I had absolutely no contact with him. I let him do his teaching. I assigned the same kind of classes to him as he’d done before, and he continued teaching that. Mr. Cox left soon after, and I had an opportunity to make a number of appointments.
Weart:In fact the department built up quite rapidly.
Weart:Just a few years after that, you had I think seven people there, including a few you shared with physics. How is it you had so many positions you could fill?
Gold:Oh, because I pulled in a fair amount of contract funds right away. And the dean kept allowing me salary recovery, half the salary from contracts were paid back, and so on. The dean stood behind me and allowed me new appointments. It was understood that I would be able to build up a department. I mean, you can’t leave a professorship at Harvard all that lightly, and I came here definitely on the understanding that I would run an interdisciplinary center, which is this present organization, which would include the construction of Arecibo; and that I would be chairman of the astronomy department, which would be expanded, and become mainly a postgraduate research and teaching place. So, as I pulled in more research funds from government sources, I was allowed more appointments.
Weart:But of course research funds don’t pay for university appointments.
Gold:No, but —
Gold:They did in fact — half. One was allowed salary recovery for half the time of an appointment. So the university was stuck with the obligation, but only with half the current expenditure.
Weart:I see, so it was relatively cheap for them to expand it.
Gold:Yes. And so I got here, I forget in what order, but Drake, Axford, Harwit and so forth, and then some years later, Sagan.
Weart:I’m interested in the funding. I notice you’ve got ONR, I suppose NSF, NASA. How, generally, have you gone about getting funds?
Gold:I don’t know. We just had sufficiently high reputation) in the sixties, for it to have been very easy to get money. I really never had any difficulty.
Weart:You would just write grant applications.
Gold:All during the sixties, I got money without any trouble.
Weart:Have there been changes?
Gold:Now, I have a hard time.
Weart:Is this because of the general funding cutbacks? Or have there been changes in the funding agencies?
Gold:Well, various things have happened, unfortunately. One is the concentration into two agencies; that I’m dependent on NSF and NASA is a disadvantage. The other is my personal standing in the scientific community — I have more enemies; more friction has accumulated over the years. You know, I don’t have quite that ease of persuading people to give me money any more. There are much more jealousies and so on. But I think that probably builds up around anybody.
Weart:Do you think this is simply a feature of your own growing older? Or do you think it’s a general change that may be happening in the community, with the funding difficulties, the funding cutbacks?
Gold:Well, they always bring such things out much more, of: courses Yes. But also, my sentiment is that if one refuses to become a conservative member of the in-group, even when one is given the option to do so — which I clearly was given, Harvard professor and on good terms with a lot of the elder statesmen in the field and so on — and if one then continues to insist on putting out and fighting for innovative notions and saying independent things, rather than swimming along, then one makes life difficult for oneself.
Gold:And that is clearly the case. That’s one thing. But the other thing is more sinister. There was a definite campaign against me personally. You will think I’m a paranoid, but I have it very clearly from sources that have looked into it carefully. There was a definite campaign against me under the Nixon regime.
Weart:That wouldn’t surprise me in the least.
Gold:It started — a connection I only surmise — it started after I had signed a document going around on the campus here after the Cambodian invasion, which many other professors here also signed, to say Nixon should be impeached for invading Cambodia. I was at that time on the President’s Science Advisory Committee Space Panel, and had been for seven or eight years. I spent a few days every month in Washington on that committee in the Executive Office building. So I was certainly on the list of people who would be scrutinized for any such “errors of judgment.” And it was shortly after that that I was suddenly no longer invited to any of the committee meetings, of which I was a member. I was just left out.
Weart:Is that so? You didn’t receive an invitation?
Gold:Didn’t receive the invitations any more. And then, the admiral who was in charge of a section of the NSF started to go out of his way, in the most fantastic ways, to throw me out of any major contracts, including Arecibo. I had to retire from the directorship of Arecibo.
Weart:Would that be ‘71?
Gold:‘70 I think. Yes.
Weart:What sort of things would he do?
Gold:What evidently happened was that the NSF was instructed by this fellow, Malik. Nixon had a special person on his White House staff, as it later turned out, whose sole job was to find out who of the persons who opposed Nixon could be hurt by withdrawal of any government funds. And the NSF of course was a main body that this Mr. Malik was in touch with. I would dearly love to get into the files of the NSF and see this in detail, but I am quite sure that it actually took place. Because it was so clear that at that time a definite campaign started; previous to that, they were all very happy with me. I’d done very good work. And suddenly, there was an enormous campaign.
Weart:Did any of the NSF administrators or referees ever talk with you about this?
Gold:No. But two of the people on PSAC told me that they had been told that I was not being invited because I was a security risk.
Weart:I see. So they played that sort of a game. Did you hear any other things?
Gold:That was one thing that hurt me very much. Apparently it did not, to the operative persons in the NSF, get down that way. What happens is that the top person no doubt is told that way, you see — and they complied, the dirty dogs. But at the lower level, they were merely told that current opinion was that I wasn’t worth giving more money.
Weart:I see. So it happens on two levels, so to speak, two different lies.
Gold:Yes. So that’s what filtered down to the people. So long as some of those people were in charge of their sections I had a very hard time. Now they are mostly being replaced, and things are going a little better.
Weart:How about on the NASA side? There’s another story there.
Gold:On the NASA side, I fouled my reputation by speaking against the (space) shuttle.
Weart:OK, I want to get back to that. That’s a different story.
Gold:There I had the following experience. Three persons from NASA phoned me, before the various occasions that I was to testify before Senate committees, just before. On one occasion, the day before, I was phoned by a senior person in NASA, who spoke to me for a long time, and then he said, “Incidentally, Tommy, I see you are to testify before a Congressional committee tomorrow. I think it would be wiser if you didn’t do that.” So I said, “What do you mean? This is a heavily organized affair. You don’t just go and tell a Senate committee, the day before, that you’re not going to go.” He said, “I think it would be better if you told them that you weren’t prepared to testify, even if it’s a bit awkward.” I said, “Why do you say that?” He said, “Of course, you must realize that I don’t have complete power over my staff. And I can’t guarantee you that there wouldn’t be somebody on my staff who would hold it against, you, in relation to the contract support that you are getting from NASA.” So I said, “You jolly well see to it that that’s not the case. But in any case,” I said, “You’re threatening me with withdrawing contract support if I testify. Let me first write you a letter and put all our conversation down right now. I will send you that letter, and I will assume that if you don’t object that you accept that.” That’s what took place in this telephone conversation “ “And secondly, let me tell you what my letter will say, namely, that my obligation to speak my mind correctly to a Senate committee is vastly more important than any Cornell contracts that might be endangered thereby.” I sent him that letter, and I’ve got it in my files.
Weart:Now, that’s one person from NASA.
Gold:The other two were minor people, but they had evidently been told. The other two were at that moment detail contract monitors.
Weart:I see the people you dealt with administratively.
Gold:Yes. They also wanted to advise me that it would be in my best interests not to testify.
Gold:I told (Senator Walter) Mondale this. One of the committees was Mondale’s committee, you see, and I told him that. And he said, “Well, do you want me to make a fuss about it?” I said, “Not really. It won’t do me much good,” He was of course absolutely infuriated at the suggestion that anybody was being shut up with such a threat.
Weart:Before that happened, had you had any concern that speaking out against the space shuttle might interfere with your relations with NASA, shall we say, your funding specifically?
Gold:I had frankly not thought that they would dare to move as brutally as they did against me.
Weart:What in fact did they do afterwards?
Gold:They made it very difficult in respect to all NASA contracts and so on. Always since that time, I was definitely a persona non grata at all levels of NASA.
Weart:What did this mean specifically?
Gold:Well, for example, I was on a lot of committees. I was on the (Lunar and Planetary) Missions Board, and had a lot of influence on the actual details of the space program. And I was thrown off of any of those things.
Weart:One by one you were dropped.
Gold:Dropped from all committee work and everything else.
Weart:But, in terms of the contracts here?
Gold:Also they started to make my life a lot harder. And then, just the fact that most of the contracts I held here were on moon work, and the fact that I’m clearly at loggerheads with most of the rapidly growing moon community — who I claim have grown too fast and didn’t really understand the thing. The fact that I’m at loggerheads with most of them means that it’s always very easy for NASA to get any number of bad opinions on any paper that I write or any proposal I submit. They just give them out to A, B, C, D and you know full well that they’re going to write back and say, “This is nothing.”
Weart:Whatever the proposal is. Right, I understand. By the way, did you ever do any work for the military?
Gold:Here? As director of Arecibo, I had a little contact with the military. But Arecibo in fact never did any real military work.
Weart:Is that a fact? It was set up —
Gold:It was set up with military money. But to them, it was mainly just the understanding of ionospheric scatter that they wanted to gain. They knew they could not make that a secret endeavor, and they didn’t even try.
Weart:I see, they were after scientific knowledge directly.
Gold:Yes. Every now and again there was a period of, “We can’t give you more money unless you do some real military work.” And then I said, “Well, all right, you can close the fence around Arecibo for two days or whatever it is, and do some military experiment, but what?” And then, “Surely there must be something?” There never was anything very good that we could do, you see. We couldn’t track anything, because we don’t have much —
Weart:Couldn’t move the feed fast enough?
Gold:Couldn’t move it fast enough, didn’t have enough coverage in angle and so on. There never was any good military experiment, really. It was constantly sort of threatened by the military in later years of Arecibo, that if I didn’t assist with some more directly military thing, then they wouldn’t fund us anymore. But on the other hand, I said to them, “You tell me. I’m perfectly willing, you tell me.” But nothing sensible ever came of it. Then eventually, I insisted that the funding must be changed over to the NSF.
Weart:Oh, did that initiative come from you?
Weart:Because it came at the same time as the Mansfield Amendment and all that sort of thing.
Gold:It was just a little before then that I started to get active; there were student protests and I didn’t want to have any thought that it was a military establishment. And also, because the military kept saying they wouldn’t be able to fund us much longer. So I insisted that it must be changed over, and I arranged eventually, through Long, who was the vice-president for research here at the time, but very much on my initiative, that Johnny Foster of the Defense Department and Don Hornig, the President’s science advisor, be gotten together with the head of the NSF to arrange for a transfer of the Arecibo funds, which was a large amount of money. And that’s what was done. Then, to my horror, I found that the moment the transfer had been done, and the NSF had the money to give us to run Arecibo, this coincided with the time that the NSF started a campaign against me personally. So I got into trouble with all the establishment then.
Weart:You gave over Arecibo.
Gold:Yes. Arecibo was disconnected from this organization and became an independent entity.
Weart:Oh, is that part of the reason that that time?
Gold:Because it was a much happier state of affairs to have it part of CRSR. That’s a complicated affair.
Weart:Do you have letters and so forth on all this?
Gold:Yes, but since you asked about that earlier, we thought about it a little bit, but it’s an awful task to dig anything out. We have dead files, you see, so the correspondence all exists, but it’s moved out to some storage place.
Weart:Have you ever talked with the university archivist here about it?
Weart:You might do that at some point. It’s his specialty.
Gold:Well, we could try. It certainly is a few days’ work for somebody who is —
Weart:Well, that’s their job, to decide what to do about such things. Certainly they shouldn’t be left in a place — as sometimes happens with dead files — where they sit for 30 years, and by that time everybody’s forgotten what they are, and they get thrown out when somebody moves — we don’t want that to happen. There must be a lot of interesting things in there.
Weart:I’m interested in Arecibo. Can you tell me more about how it was built up and particularly your own involvement?
Gold:Yes. In ‘56 or ‘57, in the summer, I was in Boulder and there talked to Bill Gordon. I start the story at what I think is the beginning. I talked to Bill Gordon, an electrical engineer at Cornell; I was then at Harvard.
Weart:Your career involves too many different things for us to cover it all in the time left.
Gold:Well, I talked to Bill Gordon at Boulder. He was Chairman I think, or concerned with at least, a committee in Washington to decide on large antennas. This was just after Jodrell Bank had been built and the question was what do you do next? I had long concerned myself, of course, with the question of big antennas, especially for planetary radar; from the earliest days I had thought very much in terms of planetary radar.
Weart:I see. You’d always had an interest in it.
Gold:Yes. And often previous to that I had said that I would have built a very, very large antenna so that you could really do these things, much larger than you would make a steerable one. I would have made one as a hole in the ground, at the right kind of latitude, so as to see the planets and see a strip of the sky. Make a very big hole in the ground. We’d already discussed this.
Gold:Yes. We’d already discussed big holes in the ground in the Whitley days, as a matter of fact. So after Jodrell Bank was built I said, “You’ve got the big steerable one, now let’s do the other thing, a much, much bigger one but fixed, and then we’ll learn better which is the right way to go.” I persuaded Bill Gordon to take a kind of a notion with him to his committee: the biggest hole in the ground you can afford. I’m pretty sure that I did in fact persuade him that that was a sensible next step to do. Then I went back to my Harvard job. I didn’t hear much from him again for some considerable time. Then Ken Bowles — he was a student here, I think — invented the incoherent scatter notion of the ionosphere, which was an important step, and Bill Gordon did too. I don’t know who invented it first, nor do I know whether either of them got the idea from the other or whether they were both independent. Ken Bowles visited here (he had by then left, before I came here permanently) and Bill Gordon was here. I remember clearly the discussion with Bowles trying to persuade a group, myself included, as to the detailed physics of incoherent scatter. The important point was whether the bandwidth of the returned signal would be the bandwidth of the electrons or the protons; it would make all the difference whether the thing was detectable or not. Bill Gordon insisted it would be the electrons, and Ken Bowles gave reasons why it would be the protons. I gave the answer, which was the correct one that the dividing line between the two theories comes in terms of the Debye length in comparison with the wave length. We wrote that on a wall in EE (Electrical Engineering building) in order that it shouldn’t be forgotten, but I think the wall was painted over since. We all went and wrote it on the wall that that was the upshot of this discussion.
Gold:A ten dollar bet was made with a fellow who was another visitor at the time, a plasma physicist from CAL, Cornell Aeronautical Laboratory. He never paid me the ten dollars, though. In fact, it must be said that if Bill Gordon had been right, then one cannot defend his proposal to build Arecibo for incoherent scatter, because it would not have sufficed to see the thing.
Weart:But this was never your main interest in Arecibo?
Gold:No. I was interested, but not principally. In any case, then I was offered the job here of setting up a center, by Dale Corson, who was then the dean of engineering. We discussed that a center would be set up, and that that center would include Bill Gordon and various other EE people, and the proposed construction of a large observatory (which by then was already in principle decided; Bill Gordon already had a definite promise of money from the Pentagon).
Weart:Were you involved in this fundraising?
Gold:No, I was not. As I said, my connection was only, I believe, that I very much put the bug in his ear in the first place that a big hole in the ground was the thing to go for. Then he came across this incoherent scatter, and used that as a justification for raising money with the Defense Department. Then I was invited to come here, and this new organization was to include Bill Gordon and Arecibo. Bill Gordon unfortunately didn’t take kindly to that. Year after year he struggled to make himself in some sense independent of this center, although the university was clearly behind me in making it part of a center because Arecibo is much too large an effort for an individual electrical engineer to be entirely responsible for. It’s all very well to be responsible for the construction, but we had to think that we had to build up teams of people to operate the thing and to use it for the many different purposes for which it could be used, including radio astronomy, which Bill Gordon knew nothing about.
Weart:Were there disagreements, in terms of the allocation of time between ionospheric and radio astronomy?
Gold:No, there never was that, because there never was pressure on time.
Weart:Even for an instrument like that?
Gold:There was never pressure on time. We just couldn’t get enough observers there — by inviting them from elsewhere or anything, we never got so many people there that there was any real pressure on time. That was never the problem. The problems were always on just the administrative say — who had the say, at various stages.
Weart:Again, the question of balance between ionospheric and radio astronomy could arise, the question of which kind of person to add to the staff or what kind of auxiliary equipment to build?
Gold:Yes, and there Bill Gordon was very dependent on me. In fact, I knew that in the radio astronomy field I had to attract people. I was responsible for attracting immediately Gordon Pettengill, whom I discovered, if I may say so, at that time out of absolutely thin air. He was just an assistant at the Millstone military radar research installation. I visited there and found this highly intelligent person, with whom I immediately had a good intellectual rapport, and I persuaded him to join us. I proposed him as deputy director to Bill Gordon down there. Bill accepted that. Many other people, Drake included and so on, I got on board for using the instrument.
Weart:I see, so there hadn’t been scientific issues involved.
Gold:That was not the problem. Bill Gordon knew full well that he would require my assistance in this regard. But there were issues — it was just that all kinds of decisions were made. Bill Gordon insisted on living down there and running the shop down there totally independently. He wouldn’t even send me any correspondence, tried to keep me as much in the dark as possible, just drove me out of the whole picture. It just seemed absurd to me that I should struggle to get radio astronomy going in a place that I was denied any other responsibility for.
Gold:What was I getting out of this, if I was just going to work hard here to get the place staffed and utilized? And that was not the initial arrangement, either.
Weart:One use of Arecibo that particularly interests me and a lot of people has been Drake and Sagan and so forth and the search for extraterrestrial intelligence.
Gold:I didn’t have anything to do with that.
Weart:What’s your feeling about that sort of work?
Gold:I don’t think there is a sufficiently high probability. I understand that the probability is small and the importance large, but it depends what you make out of that product; I still think that is very small.
Weart:Do you get comments about this sort of thing? How do you feel most people feel about this use of the facility?
Gold:I feel that telescopes can use dead time on it, and it should be on a computer-organized program of search. But it’s not enough justification to take a telescope off good scientific work. There’s plenty of dead time, even at Arecibo, even now. There certainly was in the past.
Weart:Tell me; what’s the general attitude around the department toward Carl Sagan, who has become a very well-known figure?
Gold:A sort of grin and smile. He’s very competent in this business. One worries a little whether he will get back to serious scientific work, when he’s so diverted by his importance all of a sudden. But he certainly is a good public speaker and a very good writer and so on, and one appreciates that.
Weart:Is it accepted as a valid way to spend one’s time?
Gold:Not always, no. There is undoubtedly a little background problem there.
Gold:It would be much more of a background problem if he was less competent. I mean, at least he’s doing a good job of it. If he faltered, if he did anything wrong in that, then of course one would feel much more criticism.
Weart:I see. He’s vulnerable that way.
Gold:Yes. That’s right. He would be very vulnerable, if he didn’t do the job very well. He’s a bit of a problem but one can live with it.
Weart:Now, to rush on — I’m interested in your work for NASA and that whole business, but it’s already 5:00, I wondered if —
Gold:You mean the shuttle testimony stuff? I gave you those testimonies.
Weart:I have them. If I could take a few more minutes, ask a few questions?
Weart:Well, I’m interested first: before the shuttle controversy arose, you were generally not opposed to the Apollo program — I wonder whether there were any important points where you think you had a particular influence on NASA’s space work? Any differences of opinion that arose that were important?
Gold:I think I had a substantial positive influence on the Viking mission. Although in my counsels on this, I kept stressing that it should be smaller, the first go should be smaller. I agreed in the end to it being of the size that it was. My voice was quite an important one I think on the Lunar and Planetary Missions Board.
Weart:Were there any specific points where there really were differences of opinion, where the scientists made a real difference? I don’t even know exactly how these things functioned.
Gold:I think we had some influence on the matter.
Weart:I’m trying to get at personalities, meetings, things that wouldn’t be on the written record.
Gold:I was known as being in general in favor of the scientific and against the manned flight enterprise. For some years, I was against it.
Gold:Even before, yes, long before. I was against the Skylab too, and still think that it was an absolute waste of time, of course. But I was not opposed to the Apollo mission. For scientific purposes you could have done far better without the men, with a small fraction of the money but with sample return, like the Russians are doing.
Weart:But at any rate you got something out of it.
Gold:But on the other hand, I said, “I realize that this is a matter that will have an enormous amount of public acclaim, and I don’t wish to say that I can judge the political consequences of such any better than the politicians can, and so I’m not willing to oppose myself to that.” But if asked about the straightforward problem of how to do the best science on the moon, I would certainly always reply, “You do that without the men.”
Weart:Was this what most of your colleagues on the panels argued?
Gold:No, many of them thought that you couldn’t bring things back without the men, and bringing them back was always regarded as very important, as indeed it was. But I argued from the beginning that lunar return is not such a terribly difficult thing. Remote control of vehicles that run around is not so difficult either. I said, “Well, you can run a vehicle around for much less money.” Because the whole mass would have been so small, you see, if you’d done it that way. You’d run a vehicle and you’d pick up things and look at them with television eyes, and put them in a hopper and send the hopper back.
Weart:How did you evolve from this to this very open opposition to the shuttle, testifying before Congress and writing articles and so forth?
Gold:The conflict sharpened up, because NASA suddenly decided to become tough, and dismissed many of the committees that were under their own auspices, but in their hair. The Lunar and Planetary Missions Board was disbanded and nothing was put in its place. (There were) several other committees that the inconvenient people were just thrown out of. It seemed to me that the whole advisory structure to NASA was really being thrown to the winds. It was a sham. They were seeking whitewashing committees at that stage, not advice any more. They had made up their mind always beforehand as to what they wanted to do, and they wanted the committees merely to go and add their whitewash to it.
Weart:I see. Before that point, you always felt that you could make your views adequately known.
Gold:Yes, to NASA, and influence them in a substantial way. As I say, I was a member of the PSAC Space Panel, and as a person who was on both PSAC Space Panel and the NASA Advisory Board, I was in quite an important position.
Weart:What brought about this change within NASA? Did the panels change? Did the panels become more adamantly opposed to manned flight, or was it a change on the NASA side?
Gold:It was when the Apollo program was drawing to a close. The panels had not opposed the manned space flight for Apollo, but many people like myself on the panels, not all but many people on them, were quite opposed to continuing a large manned presence in space, when you had no real mission for them. To just whirl them around in a little tin can and make propaganda that the tin can is bigger and there are more people up there and they stay up longer, and all the rest of it. Many of us were very dissatisfied with that next step. And when that next step went so far as to say, “We will not even send off two already-built vehicles to the moon, because it will cost us a little more to send them to the moon. Instead we will use that money to build a Skylab.” — then many of us were really annoyed.
Gold:That was done entirely against almost all the advice they got. There was an aerospace industry interest in it — but very much against all the scientific advice NASA had. I think it was an absolute disaster. Skylab was three billion dollars absolutely blown. It did nothing. We have a few solar pictures, but by golly, I could have gotten those solar pictures for a great deal less than three billion. For the rest, it did nothing. Spiders crawling and guppies right way up or the wrong way up, or something.
Weart:Well, we have many other questions I could talk about, but I have to let you go now.
Gold:Yes, I know.
Addition to Weart InterviewWe did not get around in this interview to two topics in my scientific work, that I tend to think are of some importance. Those are the interpretation of pulsars as rotating neutron stars, and, more recently, the discussion of outgassing of the Earth, its relation to earthquakes and to the problem of sources of fuel. The pulsar story, from my side, began with reading the discovery article by Jocelyn Bell and others in Nature in February 1968. I was very excited about it, and thought immediately in terms of rotating neutron stars, although pulsations of white dwarfs were mentioned in the discussions of the Cambridge group. My reasons were firstly the precision of the timing—I did not think that any process where the errors of individual oscillations would accumulate could give the high long-time timing precision quoted. A succession of explosions, each taking its timing from the preceding one, is not the prescription for a clock of accuracy better than one part in io8. But then there followed quickly a set of other arguments, as given in my first brief note to Nature (Nature 218, 731, 1968). Nature published my note with extreme speed — I think two weeks from submission. But before it was published there was a conference organized by the NASA New York group (Robert Jastrow, director) with Al Cameron the chief organizer. I had already discussed my view with him over lunch in Washington. I suppose it was at the AGU meeting, and he had said he considered it extremely unlikely as an explanation. At the New York meeting he and the other organizers would not even grant my request for five minutes, out of a two-day meeting, to explain the rotating neutron star picture. Instead the meeting was devoted to white dwarfs, how they could be made to oscillate faster than one might have thought, and all kinds of things that seemed very improbable to me; the second day was devoted to the discussion of optical observations that turned out to be all wrong. Later this experience gave me a great boost. To realize that a theory that was so completely ignored would be considered “obviously correct” a few months later, showed that one must stick to one’s convictions. For me this had been a nice race, with all competitors on the starting line at the same time. In June of that year there was a conference in Trieste devoted to this, and I gave a detailed account of my reasons for the neutron star story (“The Nature of Pulsars, Survey of Present Views”,Proc. Int’l Symp. on Contemporary Physics, Trieste, Contemporary Physics 1, 477, 1969). Ginzburg from the USSR was the chief speaker and gave some complicated story why it was pulsating white dwarfs, and he completely ignored and in private ridiculed my contribution. It annoyed me that a year later he was invited to give the main address at the International Astronomical Union meeting on the theory of pulsars. He discussed it as if he had invented the rotating neutron star theory, gave no reference to me. The Soviet astronomer Ambartsumian said to me afterwards that he felt very embarrassed, and that I should have been asked to give this main lecture. Cameron also published a paper that conveniently forgot the earlier history and referred to the rotating neutron star story as merely “generally agreed” or some phrase like that. Of course it was the verification of a list of predictions that put the theory firmly on the map. Pulsars in supernova shells; pulsars much faster than 1/4 second even; young pulsars the fastest; and then even the expected general slow-down first seen in the Crab pulsar, then soon in many others. And then even the Crab slow-down fitting as the hitherto unknown energy source of the Crab shell. All this story had seemed to me as if I had thought it out in response to the discovery. But in fact I later found that I had said in 1951 already, at the Massey conference on Dynamics of Ionized Media in London: “The most favorable conditions of this sort would be expected in the neighborhood of collapsed, dense stars. Their magnetic field must be stronger than it was before their collapse, merely as a result of compression in a time short compared with the decay time; and as a result of the high value of the gravitational force at the surface any atmosphere or corona would be less extended than in the case of an ordinary star. If those conditions of “magnetic insulation” are essential for the generation of intense radio noise, then we should expect radio stars to be in practice invisible or very dim. “One would, I think, feel more confidence in such an interpretation if the radio signals showed substantial fluctuations like those associated with solar activity. Their steadiness over times which are at any rate millions of times longer than the transit time of light across the size of the source seems to run counter to such an explanation.” (“The Origin of Cosmic Radio Noise, T. Gold, Proc. of the Conference on Dynamics of Ionized Media. University College Report, London, April 1951.) sI.1 Pacini had written a year before the pulsar discovery about the possibility that rotating neutron stars could be the power source for supernova remnants. But then he did not identify the pulsars with this in the first place — I don’t know why not. I had not concerned myself with the supernova discussion before pulsars, and had no knowledge of his paper, although he had written it while at Cornell. The other subject in which I have been engaged how for 1-1/2 years is the outgassing of the Earth, the sources of carbon and oxygen to the surface, and the connection of this to the earthquake process. There is the promise in these considerations of understanding and predicting earthquakes, of understanding better the evolution of the atmosphere and with that perhaps also the major changes seen in the geologic record, and, lastly, there is the possibility here that I consider very real, of tapping a virtually limitless source of methane for fuel. It is a matter of great surprise to me that this set of ideas, this avenue, should not have been pursued before by anyone. Yet I have been able to persuade very knowledgeable people of my views, and I have had no serious criticism in the lectures I have given. It is clear, therefore, that, right or wrong, it was a line that should have been investigated by the profession, and that was in fact strangely overlooked.