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Oral History Transcript — Dr. Basil J. Hiley

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Interview with Dr. Basil J. Hiley
By Olival Freire
At Birkbeck College, London, England
January 11, 2008

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Basil J. Hiley; January 11, 2008

ABSTRACT: In this interview Basil Hiley discusses topics such as: family background; nuclear physics; Cyril Domb; quantum mechanics; Hermann Bondi; University of London; Birkbeck College; Dave Bohm; Werner Ehrenberg; John Bernal; Maurice Wilkins; Roger Penrose; Leon Rosenfeld; Rudolph Peierls; Louis de Broglie; Schrodinger equation; Hamilton-Jacobi equation; Alan Wilson; Abner Shimony; Georg Wilhelm Friedrich Hegel; Alberto da Rocha Barros; Marco Fernandes; Mario Schenberg; determinism; philosophy; chaos theory.

Transcript

Freire:

Okay. We are at Birkbeck College, London, and January 11, 2008 with Professor Basil Hiley. So, we may begin to talk about your background. Give first the stats, high school and especially from where comes your interest in science? (Hiley: Okay.) And after that, in physics, in research.

Hiley:

Well, my background is probably somewhat strange because I was not brought up in England where we are now even though I am English. I was born in Burma and this was before the outbreak of World War II. But then, I grew up in India while World War II was going on. So, my background was really a part of the British Raj, as it was called. Okay? My schooling actually was not very good, because we were moving from place to place (Freire: Uhm-hmm) every six months or so. But what I did have was a lot of freedom. And fortunately that freedom, I think, was very important for me.

Freire:

And your parents, I suppose, were civil servants for the British government?

Hiley:

My father was military.

Freire:

Military? Okay.

Hiley:

My family is steeped in military. (Freire: Okay.) But I did not go into the military [Laugh] at all. But, thatís the background; my family was part of the British Raj establishment, as it were.

Freire:

Yeah. And, your high school where, where did you conclude your high school?

Hiley:

My high school was actually a very good school. Because, I came back to England at the Partition of India, which was when I was twelve years old. (Freire: Yeah.) I was twelve. So, I returned to England to go into a secondary school. And, I was very fortunate to get into a grammar school in the New Forest called Brockenhurst High School in Hampshire, England.

Freire:

Okay. And, your undergraduate studies?

Hiley:

My undergraduate studies were at Kingís College, London. What influenced my choice to go there was my physics master at Brockenhurst.

Freire:

Brockenhurst?

Hiley:

Brockenhurst School. Actually he, my physics master, had a first-class honors degree in Physics from Kingís College, London. He and I got on very well together and because of his background he said, ďWhy not go to Kings?Ē And, I thought, ďWell, why not?Ē So, thatís where I ended up.

Freire:

Okay. And, about the teachers and the, who have influenced you during this time?

Hiley:

During the university time?

Freire:

During the university times, or even before.

Hiley:

Well...

Freire:

Or even before.

Hiley:

It was my physics master (Freire: Yeah.) Mr. Burridge, who (Freire: Burridge?) was really a first-class teacher and a real inspiration for me. But, we also had a very good mathematician, Mr. Pierce. And those...

Freire:

Mr.?

Hiley:

Pierce.

Freire:

Pierce?

Hiley:

Yes.

Freire:

Okay. Okay.

Hiley:

And these two people really influenced me, well encouraged me in the direction I was going. I think I always knew I was going for science and I always knew I was going for physics with mathematics, from a very early age. I mean, at eight I was doing algebra and things like that off my own bat. (Freire: Okay.) Because, I just loved it.

Freire:

Okay. And what — so.

Hiley:

And then I was going to say, at the university I was a little bit disappointed in the teachers there because in the first two years I wanted to ask questions about relativity and about quantum mechanics and about the foundations of these subjects, but I was kept being told not to worry about all that but to pass the exams — so, I was very disappointed until the last year as an undergraduate.

Freire:

Yeah. And about your early interests in foundational science in general, from reading some, some excellent book may have influenced your interests? Or...

Hiley:

Itís very difficult to say. I mean, there are two books that, that come to my memory almost immediately, and one was James Jeansí Mysterious Universe. Okay? One of my school masters said, ďI have a copy here. (Freire: Okay.) Would you like to buy it?Ē Well, could you put it off just a minute?

Freire:

Yeah.

Hiley:

Iíve got to find it. [Recording paused]

Freire:

Itís okay. So, you were speaking about books which made...

Hiley:

Oh yes. And I said that I...

Freire:

Jean...

Hiley:

Jeansí Mysterious Universe. (Freire: Yes.) Okay. This is while I was still at school. And also George Gamowís book, Mr. Tompkins in Wonderland, I think it was. I think those two really did fire my imagination. But, I always was interested in science. I mean, at school we had a good physics master and he always was willing for me to talk about all sorts of topics in physics and so it was really that interaction that inspired me. And then when I got to university I was expecting a lot more than I got. It wasnít until the final year that I began to get people who really were talking about the things that I was interested in.

Freire:

And, and was it the support from your family to, to make a career in science? How did they react when you, it was clear that you, you were going into science?

Hiley:

It was clear what I wanted to do and I, as far as I know, there was no opposition, and there was no real encouragement either. There was, you know, the point was they wanted me to get a good education, considering my background and almost a lack of early education. And so, I think they were just very pleased for me to do whatever I wanted to do. I had no science background in my family at all.

Freire:

Yeah. This is important.

Hiley:

Yeah. No. No — my father had worked his way up in the ranks, (Freire: Yeah.) through, got a commission while he was in India. So, he was a professional soldier who was, who was a simple man. I donít mean that in a derogatory way. He was someone who was not really thinking about the deep philosophical issues of life, but was a solid dependable man. Whereas, my mother was much, much, much sharper. I cleaned up a lot of my philosophical and political discussions with my mother (Freire: Okay.) because she was very fiery and was willing to discuss all these things with me at length.

Freire:

Okay. So, when you went to your graduate doctor studies?

Hiley:

Let me say first of all in the final year (Freire: Yeah.) in my undergraduate...

Freire:

Oh so, okay.

Hiley:

I actually was involved in a bit of research work with Professor Louis Elton. My final year project actually resulted in a paper printed in the Physical Society. So, I was already on my way to doing research while I was an undergraduate.

Freire:

And which was the subject?

Hiley:

This was nuclear physics. It was The Form Factor of Carbon-14.

Freire:

Okay.

Hiley:

It was some scattering data and I was trying to fit the scattering data to a cross sectional calculation.

Freire:

So, I suppose then there was a swift and quick transition from your undergraduate studies to your graduate studies?

Hiley:

Well, the question then was, ďWhat am I going to do my research in?Ē

Freire:

Yeah.

Hiley:

I was offered a grant, a government grant, they were called SERC Grants then, to do, for three years, to do my Ph.D., and I decided I would do it in the Physics Department at Kingís with Professor Cyril Domb.

Freire:

Could you?

Hiley:

Cyril Domb, D-O-M-B.

Freire:

Okay.

Hiley:

And, to do it in the area that he was an expert, obviously, I mean.

Freire:

Yeah.

Hiley:

And, he and I got on very well together. I remember — and this, this topic I should say was condensed matter physics and it was about the Ising Model, because Cyril Domb was an expert on the Ising Model of Cooperative Phenomena. And so on. Also at Kingís, remember, earlier was Maurice Wilkins who had gotten the Nobel Prize for (Freire: Uh-hmm.) DNA. I also had, in the same thesis, a study of coiling properties of polymer molecule, long-chain polymer molecules in solution. That was sort of inherited from the activity in the Physics Department at Kings. The problem was suggested to me by Professor Michael Fisher

Freire:

Okay.

Hiley:

Now, notice there is no quantum mechanics!

Freire:

Yeah. That, thatís the question I was wondering, because after that you went to quantum mechanics but foundation of quantum mechanics in a very mathematical approach, a very mathematical approach to quantum mechanics. So, what I was wondering, from, from where comes your mathematical background?

Hiley:

It comes from my days in India when I had this little book on higher algebra for schools, for Indian schools, which was a sort of a bible for me. I would, you know, go into a corner somewhere and work out the problems. It was just something that came very natural to me. I was very excited by it. And, as I went through my undergraduate course I always kept the mathematics going. I had a very great interest in the mathematical sciences. And, when I got into the graduate school, the condensed matter subject I was working on was, in fact, mathematics. To put it officially, it was embedding finite graphs in various regular tessellations. But it wasnít the mathematics that I really wanted to study. While I was doing my Ph.D., I would go and listen to Professor Herman Bondi. He was a brilliant lecturer, Herman Bondi. He had a very active school in the Math Department at Kingís. And, at the time there was this big debate about the Universe, whether it was a continuous creation or a Big Bang. And, because of my interests in the Mysterious Universe, James Jeansí background, I was very fascinated and I used to go to the lectures that were held in the Math Department. There were people like Herman Bondi, Thomas Gold passed through. There was Clive Kilmister, an expert in works of Eddington, someone whose writings I found extremely interesting. There was Felix Pirani. In fact it was a very active group.

Freire:

Oh, very.

Hiley:

Some of the time I was in the Math Department. Not officially, but unofficially just enjoying the intellectual stimulus.

Freire:

Very, very interesting. So, at the time you, you didnít begin yet to, to think about quantum mechanics, about foundations of quantum mechanics? In fact...

Hiley:

No. No, because there wasnít any real interest in the subject at that time. Nobody was really interested in it. Yes, I had been fascinated by George Gamowís book, and Iíd had a series of lectures in quantum mechanics. I wonít say by whom, but the person didnít really understand the subject. So I used to come up to University College, because it was just a twenty-minute walk between the two colleges. There I attended the lectures of Sir Harry Massey and some of the other University College staff (Freire: Okay.). So, I was learning my quantum mechanics from that source. (Freire: Okay.) So, I wasnít concentrating on my Ph.D. in the sense of just doing my Ph.D. I was also trying to think about these other problems at the same time.

Freire:

Okay. Now, I know that you began at Birkbeck College in 1961?

Hiley:

Yes.

Freire:

And the period you began to collaborate with Dave Bohm?

Hiley:

Yes.

Freire:

Okay. I want to understand. It seems that — so your, your connection with David Bohm it comes before you came to be at Birkbeck College?

Hiley:

Yes.

Freire:

Okay.

Hiley:

Shall I tell you?

Freire:

Yeah.

Hiley:

Because, itís not a very long story but itís a very interesting story. At the end of my Ph.D., after my three years, I had, I think, three papers already published. So, there was no problem about me getting my Ph.D. All I had to do was to write it out and then polish it up and so on. In the April of my final Ph.D. year, I think it was, I went to Cumberland Lodge. Now, this is a big house in Great Windsor Park and the lady who owned the house, I canít remember what her name is now, used to encourage groups of people from the university, from each of the colleges, to come and spend a weekend there in order to get some extracurricular activity. What happened was the Maxwell Society, which was the Physics Society of Kingís College, the student society, arranged a meeting this April and there was this guy called David Bohm coming. (Freire: Okay.) Right? Now I didnít know anything about David Bohm. I may have been aware of his textbook, but nothing special. I went and sat in the back of the lecture, because Iím very, I get irritated sometimes and I like to leave, so I sat at the back thinking Iíd give him a little bit of time and then I would leave. When he started I was absolutely spellbound. He was asking the sort of questions that I had been worrying about as an undergraduate, and not only that he was giving some answers, but his attitude was, you know, ďAnd you out there can come and help and do this kind of thing.Ē This was, oh it was, I canít describe, and words donít capture my excitement. He gave two lectures and at the end I said to my wife, who was actually there in the Cumberland Lodge with me, because you know you could bring your wives and your family with you. And I said, ďIím going to work with this man.Ē Now, I was very fortunate, of course, because in the Ď60s the universities were expanding and jobs were very easy to come by. Not like now where you, you know, youíve got to serve on, oh youíve got to serve years (Freire: Yeah.) before you even get a look in. A vacancy came up at Birkbeck College and there was one also at Sheffield University and Leeds University was trying to find someone. I went up for the interview in Sheffield and they actually offered me the job on the spot. If I had accepted I would be joining Norman Marchís group to continue my work in condensed matter physics. But, there was also an interview coming up at Birkbeck. So, I said I wouldnít accept straight away, that Iíd think about this Sheffield offer. I came to an interview at Birkbeck and they offered me the job! Now I knew that David Bohm had just taken the chair of Theoretical Physics at Birkbeck. I was also very impressed with the people who interviewed me. There was J.D. Bernal, who was an intellectual giant. A brilliant man, unfortunately I only interacted with him for about nine months before he had a massive stroke and that really incapacitated him. And there was also Werner Ehrenberg, who was...

Freire:

Who?

Hiley:

Ehrenberg.

Freire:

Ehrenberg. Okay.

Hiley:

Ehrenberg was an extremely interesting and very gentle physicist. He made me feel at home almost straightaway. Fortunately they offered me the job and I had no hesitation in accepting it. And, that was really the beginning of my collaboration with David Bohm.

Freire:

Yeah, now I can understand why David Bohm said in the interview with Maurice Wilkins that you were already at Birkbeck (Hiley: Yes.) when he, when you began to collaborate?

Hiley:

Yeah, because I was still finishing off some papers, (Freire: Yes.) on my solid state physics. And remember, as Iíd done most of my work in solid state physics, I had to now come up to scratch in foundations of quantum mechanics and general relativity and so on. Although Iíd been to these other lectures at Kingís and University College, I hadnít really studied them as hard as I should have done. So, the first four years or so (Freire: Okay.) I was making the transition.

Freire:

Now, before going forward, you talked about John Bernal?

Hiley:

Yes.

Freire:

May you, maybe you remember what kind of impression you had about him before you; you come to Birkbeck College as a physicist, as a crystallographer, as a politician, a socialist?

Hiley:

I had heard rumors about his political views. Because, you know, I was in Kingís and therefore I was interacting with the staff in Kings, picking up the gossip. He was well known because he was a very strongly committed communist. Also I heard stories about how good he was in science — but it was all hearsay evidence. I think I tried to read one or two things of his. It was really, my real impression was — once at a lecture here at Birkbeck when Maurice Wilkins gave a lecture on RNA, and it wasnít — I shouldnít say this — but it wasnít the top- quality, dear Maurice! [Laugh] (Freire: Uh-hmm.) Then, Bernal got up and gave a twenty- minute summary and it was brilliant. It was clear. It was precise. It was to the point. And thatís really where suddenly I recognized that here was a really, really first-class brain. And so really I didnít — and the politics didnít worry me because there was, you know, there always is this put down, ďOh, heís a communist. What do you want to work for him for?Ē But politics was not my main interest and so that none of that came out in the discussions.

Freire:

I only know he has a great interest in the history of science?

Hiley:

Yes, that...

Freire:

The book ďThe social function of science.Ē

Hiley:

That didnít impress me.

Freire:

Okay. But in it he writes in it very clear (Hiley: Yes.) about it.

Hiley:

Yeah. Yeah.

Freire:

So.

Hiley:

You see of course there was always all that stuff which didnít really interest me. I was more interested in physics of polymer molecules, the DNA stuff that was going on, and here was Bernal who actually really started the whole project, which enabled Maurice Wilkins to work on the structure of DNA which eventually got him the Nobel Prize. Of course there were others who contributed massively to the project, but I knew Maurice so I could relate to the work through knowing him.

Freire:

Yeah. Okay. Now, let me put a question, and Iíd like to have your comments. So, you begin to work with Bohm in a moment. Bohm was moving from his previous Hidden Variable Approach to quantum mechanics to a new approach? That is right?

Hiley:

Yeah, when I started with Bohm we did not mention or discuss his Ď52 Hidden Variable approach at all.

Freire:

Yeah. This is very interesting. So, [Laugh] this is very interesting.

Hiley:

I think you ought to realize that Roger Penrose was here at Birkbeck as well, and Penrose, Bohm, and myself, together with two or three others, I forget who they were, used to meet fairly regularly on Thursday afternoons in University term times and we had discussions, far-ranging discussions. I think Penrose was just beginning to develop his ideas on twisters, and I got very fascinated with that side of the mathematics — essentially Clifford Algebras. There is an interesting local connection here. Clifford was a past professor of mathematics at University College, London, so he worked next door! I was aware of his work through my contacts at University College. David Bohm, when he came to Birkbeck, was really talking about a radical new theory to try and understand quantum theory. Much of his thinking at this time is contained in the book ďBohm-Biederman CorrespondenceĒ edited by Paavo Pylkkanen. And, as I say, for about the first ten years we didnít discuss the Hidden Variable Theory at all. Now, why didnít we discuss them?

Freire:

Let, let me confirm, so let me give you a piece of information which match what you are saying. When you, one sees the record of publications of David Bohm, during the Ď60s you have no publication about hidden variables. (Hiley: No.) Except at the end of the Ď60s there is a paper which he gave a model of hidden variables with Jeffrey Bub, (Hiley: Yes.) Ď68 or Ď69. But, in a very different manner from the first (Hiley: Yes, Yes.) hidden variable (Hiley: Yeah, Yeah.) approach?

Hiley:

Well, Jeff was one of our first Ph.D. students who came straight from South Africa. (Freire: Yeah.) He was more philosophically inclined and interested more in the proofs of why people had concluded no hidden variable theories were possible without violating the results of the standard formalism. This took him to different HV theories, theories very different from the Hidden Variable Theory of Ď52.

Freire:

Yeah. Yeah.

Hiley:

His work with Bohm was based on the Weiner-Siegel idea that you could use a pair of Hilbert spaces and the interaction between this pair of Hilbert spaces would allow you to collapse the wave function. Okay. Also I know Jeff was very much involved in very heated arguments with Joseph Jauch (Freire: Yes.) and Constantine Piron, from Geneva. (Freire: Yes.) And, there was an exchange of letters. There are also some papers that came out of the result of this. I always tended to be on the sidelines of this because I never felt that the Hidden Variable Theory was the right way to go. Now, Iím not quite sure why I had that point of view. First of all, I think, I was brought up in an atmosphere where it was generally agreed that there was something basically wrong with the Ď52 paper of Bohm. But, there was more to it than that. There was a general atmosphere in physics, that there was something, I would almost say ďevilĒ about it, and I never understood why there was that feeling around. It seemed that if somehow you touched it and thought about it, it would corrupt your physics forever more. (Freire: Uh-hmm.) Extraordinary feeling, totally irrational, but that was the atmosphere that was around at that time.

Freire:

And this is very interesting because you are talking about an environment, an intellectual environment. So, which intellectual environment, at least London intellectual environment? So, you are not talking about an American (Hiley: Right. Right.) Intellectual environment or elsewhere? So, one, one possibility, so you remember the paper I sent to you? How influential Rosenfeld was in Britain, in England?

Hiley:

Well, Iím not sure how Rosenfeld fits in, but you see there was Rudolph Peierls, for example, and he was very strongly against any interpretation of quantum mechanics except the interpretation of quantum mechanics. I think he influenced a lot of people. John Bell, who was supervised by (Freire: Yes, Yes.) by Peierls, and that was an interesting [Laugh] relationship in itself. But I must say I donít know where this feeling came from. It was something in the air. (Freire: Okay.) Because I remember once when I was in our little staff library in Kings College and I was looking at de Broglieís book on the Double Solution and I became rather interested. I was just glancing through the pages to see what, what he was saying about it.

Freire:

And what time was this?

Hiley:

Oh, Ď59, Ď60.

Freire:

Okay. Okay.

Hiley:

That vintage. Because, it was while I was still doing my Ph.D.

Freire:

Okay.

Hiley:

And, my supervisor came up to me, not Cyril Domb, another, and he said, ďWhat are you reading that for?Ē And I said, ďWell, Iím interested.Ē So, he took it from me, shut the book and put it back on the shelves. He said, ďDonít waste your time reading that book. Get on with your Ph.D.Ē

Freire:

Wow. Very interesting.

Hiley:

Now, you know, what was all that about? And, the guy was a very, very clever guy as well. But, if that kind of thing happens to a young, impressionable research student trying to find his way, it makes you think, ďWhat is going on here?Ē

Freire:

But, about Rosenfeld, just to make a point. At the time, at least two opportunities, he ran against publishing and thinking about Bohm, in thinking about hidden variables, in England. He, he was the referee of the papers Bohm submitted to Nature, submitted through Massey, (Hiley: Uh huh.) yeah, and the paper was (Hiley: Rejected.) never published. (Hiley: Uh huh.) And...

Hiley:

But, I wasnít familiar with that story, I didnít realize they spent...

Freire:

Yeah. And, that book of de Broglie, he also wrote a report against the publication. (Hiley: Uh huh.) But, theÖ

Hiley:

Maybe that was where the information was in the general environment (Freire: Yes.) in the physics community in England.

Freire:

Yes. Yeah.

Hiley:

But, I know I did read the Colston lectures. There (Freire: Yeah.) Bohm and Vigier were invited to present their work in Ď57. And, the paper by Rosenfeld was an extraordinary paper when I read it, because he, it accused Bohm and Vigier of revisionism, and I went, ďWhat?Ē You know, to me this was an extraordinary statement to make in a scientific debate. So, there was this, I think there was a lot of politics mixed up in the (Freire: Yeah. Yeah.) in physics.

Freire:

Sure. Sure. You wrote in a letter to me a very interesting thing, that when you realized that Rosenfeld was also Marxist you may understand how fierce were (Hiley: Yeah.) the critics, because they are fighting among Marxists. I alwaysÖ

Hiley:

Yeah. (Freire: Yeah.) But, that letter was written much later (Freire: Yeah.) though. But, I mean I donít even know, is that true? Was Rosenfeld a Marxist?

Freire:

Yes. Yes.

Hiley:

So that, it wasnít until much later when someone told me about Rosenfeld that I then said, ďAh, that is why there was such, such a violent clash between Bohm and Vigier on the one hand and Rosenfeld on the other.Ē

Freire:

Yeah. And he was always a Marxist, whereas Bohm gave up Marxism in the end of the Ď50s, (Hiley: Yes.) Ď57, Ď56. Rosenfeld kept himself as a Marxist, but a very special kind of Marxist, which Anja Jacobsen, she has a few papers, historical papers. You may see the reference about the kind of Marxism Rosenfeld

Hiley:

Okay. Iíll be interested (Freire: Yeah.) in that. (Freire: Yeah.) Because now suddenly this throws a whole new light on the subject.

Freire:

Yeah, Yeah, Yeah. Now, a question which seems a little ironical, thatís a question I put it here. One, one can say that in the Ď60s you and David Bohm were developing, beginning to develop the mathematical approach or structure for this general idea of order, the rule of order, the rule of implicate and explicate order? (Hiley: Yeah.) But, but maybe I am completely wrong but I would like to hear it from you. The first papers, you and David Bohm coauthored, which you are well....

Hiley:

Iím sorry, I didnít catch that.

Freire:

Which was, the first paper, you and David Bohm wrote together?

Hiley:

Yeah. Okay. Yeah.

Freire:

Which were very widely received, at least if you may check in the number of citations. Were papers in which you, you explained some physical, quantum physical effects in terms of the idea of quantum potential. So.

Hiley:

Okay, by that time weíd actually taken up the paper again. Itís an interesting story as to how that happened. As I was developing the mathematics that we were trying to use, because of the influence of Penrose and the Clifford Algebra structure he was interested in. You must realize this was slow work. We just couldnít go and find the relevant mathematics and apply it. We were, probably foolishly, trying to start from scratch.

Freire:

So, my explanation, my question (Hiley: Yeah.) is related, how, how then was there a kind of coexistence between two different approach? I understand clearly that when Bohm and you resumed the Hidden Variables approach in the middle of the Ď70s, was no more exactly the 1952 paper. (Hiley: Okay.) They were different. But anyway, these were two different approaches?

Hiley:

Yeah. Yeah. Sure.

Freire:

So, so how do you think both?

Hiley:

Well it came about because we had a couple of research students working for us, Chris Dewdney and Chris Philippidis. They came to me one day with Bohmís Ď52 paper in their hand. And, they said, ďWhy donít you and David Bohm talk about this stuff?Ē And I then started saying, ďOh, because itís all wrong.Ē And then they started asking me some questions about it and I had to admit that I had not read the paper properly. (Actually I had not read the paper at all apart from the introduction! And when I took it and, so, you know, I was now faced with embarrassment that our research students [Laugh] (Freire: Yeah, Sure, Sure.) were putting me in, (Freire: Sure.) [Laughter] in a difficult position, and so I went back home and I spent the weekend working through it. As I read it, I thought, ďWhat on earth is wrong with this? It seems perfectly all right. Whether thatís the way nature behaves is another matter.Ē But as far as the logic, the mathematics, and the arguments were concerned, it was sound. I went back again to see the two Chrisís again, I said, ďOkay, letís now work out what the trajectories are, work out what the quantum potential looks like in various situations.Ē And this is where I think Chris Dewdney did a lot of very good work. He produced these calculations, and of course once youíve got images (Freire: Yeah.) they are worth more than a thousand words. And suddenly we began ask the question, ďWell, you know, what is the physical origin of this quantum potential? Why is it there?Ē Heisenberg had originally criticized it by saying it was ad hoc. But, how can something be ad hoc when it comes out of Schrodingerís equations without putting anything new in. It came out just by splitting the equation into its real and imaginary parts under polar decomposition of the wave function. And so, that was really the focus of my interests, that this was not some new formalism. This was quantum mechanics, but being expressed in a different form. Furthermore in a language which was much closer to classical physics so that at long last we can find out what, find an answer to the question, ďWhat is the real difference between quantum mechanics and classical mechanics?Ē We couldnít do that before because the two languages, the two mathematical languages seemed to be totally foreign to each other. But, if you just polar decompose the wave function and look at the real and imaginary parts of the SchrŲdinger equation you get a mathematical form which is so close to classical physics.

Freire:

Itís, I know, the Hamilton-Jacobi equations.

Hiley:

Yeah. Because youíve got the Hamilton-Jacobi equation. (Freire: Yeah.) And so then suddenly my interest started to develop. ďWhy? What is this? What is the origins of the Hamilton-Jacobi Equation?Ē etcetera, etcetera. And so the position I adopted here was, ďLetís find out what are the properties of this quantum potential to see if we can begin to get some physical insight as to why itís there.Ē I hope this helps to explains why we suddenly became very interested. Or maybe why I became very interested. [Laugh] And, I think David also, it revived his interest when he saw the trajectories and the quantum potential, you know. He was surprisedÖ

Freire:

Is that the images, the images of it?

Hiley:

Yeah. The images. His eyes suddenly, you know, popped open and now he started, then he and I started talking about this in earnest. We also had an experimental physicist called David Butt in the Department.

Freire:

Who?

Hiley:

Butt. B-U-T-T. (Freire: Okay.) He was an experimentalist in Birkbeck College and a very interesting guy, and he actually said, to me, he said, you know, he said, ďI think we can find some experiments to see whether this non-locality really exists in the quantum potential or not.Ē I think that was also another impetus. This was just; this was after the Bell Inequalities came out, but before we knew of the existence of the Bell paper. Because, you know the Bell paper was in the journal Physics, (Freire: Yeah.) which folded after a few editions. And in those days there were no computers to...

Freire:

Yeah. Yeah. Yeah. To recover it.

Hiley:

To recover the papers quickly. (Freire: Yeah.) And so, (Freire: Yeah.) it took a bit of time (Freire: Yeah.) for me to find the paper. But, we were actually designing experiments. And I say, ďwe,Ē really credit must go to David Butt and his research student June Lowe. Note they were beavering a way before Aspect, trying to see (Freire: Sure.) whether if you moved these detectors further and further apart so youíre really looking at space-like (Freire: Yeah.) separations between the instruments when youíre making your correlations measurements to see whether the non-locality would disappear, and it didnít. You know, they moved it out to six meters and then out to twenty-three meters and there was no change. That was when we were facing this idea that weíve got to take non-locality seriously.

Freire:

You talked about Burt, B-U-R?

Hiley:

B-U-T-T.

Freire:

B-U-T-T? So, thatís the same paper which came, with Wilson, yes?

Hiley:

Yes, Wilson. Alan Wilson was a young lecturer here at Birkbeck. (Freire: Okay.) I should have mentioned his name. But he unfortunately, he was very keen on mountaineering and not very long after that paper was published, he fell off a mountain and was killed. (Freire: Oh.) It was a real tragedy.

Freire:

Terrible. Terrible. Yes. Now, just as you talked about the appearance of Bellís paper. One thing I was always puzzled as a historian was why Bohmís reaction to Bellís paper, to Bellís theorem paper? Iím speaking about 1965, Ď64.

Hiley:

Sixty-four. Yeah. Yeah.

Freire:

Paper Ď64. Because, there was a reaction of Bohm in that paper with Bub, but itís a reaction to the review, the paper in Review of Modern Physics they built a kind of model which Papaliolios tried. So, this was Ď67, Ď68, Ď69. At that time I would say that in the United States Clauser and Shimony, in a definite manner they were grasping the full implication (Hiley: Yes.) of Bellís theorem (Hiley: Yeah.) and they came out with a 1969 paper, the CHSH paper. So, one thing I always asked, why Bohm was not the first to, to — so, you were, were talking that the paper, in fact, it was not known at the time?

Hiley:

Oh, it was not known to me. Now, if it had been known to Bohm and he thought it was important I would have got to know about it.

Freire:

Probably. Probably.

Hiley:

Probably.

Freire:

Yeah.

Hiley:

But, it doesnít always follow, because, you know, because Bohm sometimes just forgets to do things. I mean, he was, [Laugh] he was like that. He was so involved in what he was doing that, you know, he would make omissions of that kind. But, 1 remember when the paper came out, when we finally got hold of a copy of Bellís paper, his reaction, Bohmí s reaction was something along the lines of ďI donít think you can actually prove non-locality in that way.Ē That doesnít mean to say that he opposes non-locality, he just felt distrust in the mathematical proof. (Freire: Okay.) Now, while I was trying to explore that possibility I actually found something which I thought was wrong with Bellís proof. I had a counter example. You see, I think Bohm, remember, Bohm had a counter example for the von Neumann Theorem — No Hidden Variable Theory, but he never quite could put his finger on what was wrong with the original proof. We had to wait for John Bell to spot that. So, Bohm has this intuition that thereís something wrong with this formalism, but he didnít like formalism per se. It had to have the intuitive backing, his intuitive backing, and then he would accept an abstract formalistic exposition of a particular point. My paper didnít help, but fortunately I spotted my own error before it got into print! (Freire: Okay.) Okay? Intuition is what a lot of physicists try to avoid, particularly mathematicians, who like to see very solid proof before theyíll accept anything. Bohm wasnít like that. He went much more on intuition. And, the amazing thing for me to observe was his intuition was nearly ninety percent of the time correct. [Laugh] And whenever Iíd try something like that heíd say, ďWell, it was wrong,Ē you know. [Laugh) No, so there was this feeling that you could not prove absolutely that something was nonlocal. When I put my paper out he was, Bohm was very excited about it and I sent a copy to — in fact, I sent it to Nuovo Cimento and I got back a reply saying that theyíd accept it. But, in the meantime I had sent a copy to Shimony and one or two others, and John Bell. John Bellís criticism was, ďWell, I donít know what youíve got wrong here, but Iím sorry the theorem is correct.Ē [Laugh] Whereas Shimony was much more perceptive. He couldnít spot the error that Iíd made but he asked some penetrating questions...

Freire:

Well, please.

Hiley:

Sorry?

Freire:

Sorry. You, spoke about Abner Shimony, (Hiley: Yeah.) what he said?

Hiley:

He wrote back again (Freire: Yeah.) and said he didnít spot the error in what Iíd done (Freire: Okay.) but he felt so confident in the Bell results that he wanted to criticize what I was doing and he raised some very interesting questions. And, it was when I was trying to find answers to those questions that I spotted that I had made an assumption in my proof, and that assumption was not correct.

Freire:

Okay. Very good.

Hiley:

So, I withdrew the paper straightaway.

Freire:

Yeah. This is very interesting, I didnít know. This is not related in any place.

Hiley:

Well, I felt a little bit [Laugh] embarrassed by the fact that I wrote a paper which was wrong.

Freire:

Yeah. But, [Laughter] you were fighting with a good problem. This is a good resolution. Now, let me come back to...

Hiley:

Before you do, can I just say one thing more about the non-locality with (Freire: Yeah. Yeah.) David Bohm?

Freire:

Yeah, go ahead.

Hiley:

Because, youíre right. Itís puzzling. Why didnít he embrace Bellís inequality? When we were writing the book much later on, The Undivided Universe, we were vacillating over the non-locality question, and I turned to David Bohm and I said, ďDavid, do you believe quantum mechanics is nonlocal or not?Ē [Laugh] And, he said, ďOh yes, yes, yes. It is.Ē But, you see there is that, there was something there that was troubling him, even as late as Ď90ís.

Freire:

Which is very impressive because at some point in his 1952 paper is said that, that model is as nonlocal (Hiley: Right.) as it is standard quantum mechanics.

Hiley:

Yeah.

Freire:

And this was not realized at the time as a strong point in the paper. But now we can see that this was..

Hiley:

Yeah, well thatís one of the big important points about Bohmís Ď52 paper — it is what led John Bell to explore this point more deeply and to arrive at his inequalities.

Freire:

Yeah. Yeah. John Bell wrote, I think, in Ď78 that ďIn 1952, I saw the impossible done.Ē

Hiley:

Yes. Yeah.

Freire:

Yeah.

Hiley:

Yeah.

Freire:

And, he wrote it after he tried to work on this subject in the early Ď50ís and Rudolf Peierls did not...

Hiley:

Oh, Peierls, yes. (Freire: Yeah.) I remember John Bell telling me once that he was giving a talk on the Bohm model and non-locality and so on, and Peierls was just sitting there quietly as chairman. And something came up in the audience and Peierls said, ďWell, the fact that Iím not saying anything does not mean that I agree or approve of whatís being discussed.Ē [Laugh]

Freire:

Yeah. There is a little book by Peierls in which he wrote a short biographical sketch about some important physicists, and what he wrote about the Bell, there is not only, no word about Bellís Theorem. He praised Bell as a good physicist, a good physicist in other fields, but not in this, this field.

Hiley:

Now, I wrote a paper, which I was asked to do for a physics didactic journal about The Interpretations of Quantum Mechanics. And, the editor came to me and asked me to do it and I did it. He then sent it to Peierls and Peierls wrote back saying, ďWhat is this man talking about? There is only one interpretation of quantum mechanics.Ē

Freire:

Okay. Very interesting.

Hiley:

The paper wasnít published.

Freire:

Very interesting. Now, let me come back to, let me say your first research program. So, this idea of mathematization, the general ideas about order, about implicate order, I know that you, you spoke about this in other places, you know the, the place Iliad seen recently a good interview with a Slovenian. Itís on the web.

Hiley:

Is it? Oh, yeah. (Freire: Yeah.) Thatís with the young boy, Perus?

Freire:

Yes.

Hiley:

I donít know what his first name is now. (Mitja Perus)

Freire:

I donít remember. So, but anyway, I thought it would be very interesting to record a general account about the development of such a problem, because itís a two-pronged, two, you are devoted to, to this program until today? [Laugh] So, I...

Hiley:

Guilty. [Laughter]

Freire:

Itís not, no. Itís not meant to — but I would like to understand a little about what were the challenges, what were the obstacles, what were the achievements? So, for instance, (Hiley: Yeah.) I would say, the paper, the 2002 paper you sent me last year I was very impressed when I under, I realized that Wignerí s distribution and Bohmís approach could be from the mathematical point of view.

Hiley:

The same?

Freire:

Yeah.

Hiley:

Certainly theyíre the same. [Laugh]

Freire:

Yeah. So, this is a kind of achievement I think so.

Hiley:

Well, this I only discovered within the last five years.

Freire:

Yeah.

Hiley:

No, I, my original — how can I create the atmosphere? In my discussions with Bohm we both felt something very radical was needed in order to fully understand the quantum laws. Okay? Clearly he wasnít happy with the Hidden Variable approach, because he felt something more general was needed. And so we were discussing this. One of the, well there are two different strands going through this early work. One was that perhaps the idea of classical point particles was incorrect and that really what we should be doing is talking about processes. So, weíd start with a process philosophy. And then the question was, you know, so we convinced ourselves that perhaps we should explore this idea of motion, of action, of movement. You see all these words coming up, in particular, in Bohmís early papers. So, itís not that something like a particle is moving, but from this general background of process we could extract out something which looked and behaved like a particle following a trajectory. Okay, so that would be a sort of a macroscopic coarse-grained view of the deeper process. Okay, so that was number one idea, that there was a deeper process from which we could extract the quantum formulas. The second idea was that maybe we should not have continuous space-time manifold in the background. In other words we need something like a pre-geometry, in Wheelerís words, or pre-space in our words. Iím not sure that ďpre-spaceĒ is the right phrase, but itís before we attribute any properties to our space and time. I came up with an idea that perhaps we could do everything in terms of structures, like simplexes. We analyze the structure process not in terms of the continuum, but in terms of a discrete simplicial complex. I was rather amazed to find that some of the equations of physics could be written in terms of boundary and co-boundary operators, in which the boundaries vanish. A point which, I discovered later, Wheeler had been exploring, and we came to a similar conclusion but from different points of view. The problem with the structural idea was that it killed off the notion of process. So, somehow we had to get structure but itís got to be structure process, (Freire: Uh huh.) and this is where the order came in. What is the mathematics that we need to describe this order? I was down at Kingís College talking with Clive Kilmister, who Iíd known from my Ph.D. days, my younger days — and he knew Bohmís work. He was very interested in Eddington. He was very interested, therefore, in Clifford algebras, because Eddington uses these algebraic techniques. He thought it was a good idea if four or five of us got together and ran a series of seminars on how different people have thought about space and time. Because at that time, remember Penrose was developing his twistors —(essentially the conformal Clifford algebra), from which he was trying to construct space-time. Wheeler was exploring his ideas using super-space and I remember him coming in to London to give a seminar. I was absolutely fascinated by the talk he gave with his sum over geometries, you see. I didnít want that idea because I wanted it to come from something cleaner, such as process. I donít like an approach, although Iíve done it myself, that comes from the classical approach by gradually loosening the constraints. I would rather start — I know this is ridiculously ambitious — start from something really fundamental.

Freire:

I would say ďradical ambition.Ē [Laugh]

Hiley:

Really radical. [Laugh] I mean, you know, no inhibitions at all. (Freire: Yeah.) And, what I found was that people like Clifford and Hamilton, and Glassman, had actually be trying to do the same thing. They were motivated by activity, by action, by movement, by process. Clifford actually had a paper, in which he found an algebra — I guess now we come to algebra — he found an algebra, which actually captured the active idea of rotation, of motors, of rotors, a geometric algebra emphasizing the activity rather than particles and fields-in (???) interaction. Also there was a paper, a very old paper by Hamilton, called The Algebra of Pure Time. Once again, he was saying that algebra is the way we can capture the idea of process. Now, what excited me? Diracís theory of the electron was essentially a rediscovery of the Clifford algebra. Right? So, hereís us trying to get this (Freire: Okay.) mathematics of process, of movement, discussing new orders within this framework and hereís Clifford, using his algebras, of which the quatemions are an example to discuss the structure of space and time. But quaternions were thrown out of physics because there was something unclean about them. (Freire: Yeah.) But here was Dirac reinventing the algebra, which is necessary to describe the relativistic electron. Thatís where my motivation came in and thatís why we werenít particularly interested in the Hidden Variables paper because that was trying to put back, as it were, the classical image and then just change it a little bit. (Freire: Okay.) By then, you see, having understood what the quantum potential by exploring its mathematical details, you could then see that it could be used to help to understand the algebraic approach, because there you can see how information, for example, might be working to organize the process into, to produce, or to reproduce quantum phenomena.

Freire:

Okay.

Hiley:

Is that OK? — Itís a rather loose description, you know, but I donít want to get into too many details here.

Freire:

No, just one source of motivation.

Hiley:

No. No. Itís a whole, itís a whole source.

Freire:

I can understand.

Hiley:

A whole series of sources of ideas, which are coming together. And now, in my very latest work, the Clifford Algebra and the Bohm Theory is one and the same thing.

Freire:

Oh.

Hiley:

Iím just writing it up now, (Freire: Yeah.) where I suddenly see that these two roads are the same. In the same way as you would, I was mentioning earlier, the Wigner-Moyal theory and the Bohm theory are the same thing.

Freire:

Okay.

Hiley:

So, thereís a much more general structure there in which all these attempts are the coming together, and you can see them as various aspects.

Freire:

Okay.

Hiley:

And, I think itís always very exciting when you see some, several different strands all coming together.

Freire:

Now, let me ask a question. I would say, maybe a more historical question. When one sees Bohmís previous works to the Ď60s papers on plasma, and even his papers on quantum mechanics, itís not, itís not easy to foresee that after he would develop such a mathematical, such an abstract approach to foundations of quantum mechanics. Now, my question is, how, how he reacted when, when you realized that you needed such kind of mathematics? Because, it seems for me that for you it was just the kind, the kind of thing you were looking for?

Hiley:

Sure. I mean, yeah, Iíve had this, yeah, sort of, implicit in the background. And itís something which, obviously, will prompt...

Freire:

I say itís a kind of your style, (Hiley: Yeah.) scientific style?

Hiley:

Itís my style. Yes.

Freire:

Yeah. But, in Bohmís case?

Hiley:

Well, I mean, I think Bohm, as I said before, Bohm had very good intuition and he taught me a lot about philosophy. But, Iím always very worried by words, because you can weave them in all sorts of magical ways and somehow you never quite know which way is the right way and you never quite know how to decide. I always felt that what I would like to do would be to take these philosophical ideas and actually do some hard mathematics with them so they werenít all airy-fairy. I think thatís been a constant drive and maybe Iíve influenced Bohm by insisting that we talk in this way, you know, that Iíd give him the chance to really weave this web of words and then sort of say, ďWell now, really, what do you precisely mean?Ē and then try and discipline the discussion and focus it more.

Freire:

This is very interesting what you are saying, because from, from a different point of view it seems that you and Bohm, you two have kind of a collaboration in which you were doing the same thing. But now, itís clear to me that there was a kind of, how do you...

Hiley:

Complementarity.

Freire:

Complementarity. Yeah. Yeah. This...

Hiley:

But not in a Bohrian sense.

Freire:

Yeah. Itís the — okay.

Hiley:

Yeah. I feel thatís why we survived together for so long. You know, that we each had our different perspective and we were hopefully influencing each other. He certainly was influencing me. And maybe, as youíve noticed, maybe because of that things changed, thatís obvious.

Freire:

Yeah. No, but I would say that somebody who looks at your papers, after Bohmís death, can understand that you, you had your own research program that you continued to develop, (Hiley: Yeah.) after.

Hiley:

Yeah. Well, it...

Freire:

It is very clear.

Hiley:

Yeah, I know.

Freire:

Yeah. Now, let me ask a few questions related to this problem. You told me that Bohm discussed a lot of philosophy with you (Hiley: Yes.) and itís very interesting that recently I, I had seen in a letter from Paul Feyerabend, the philosopher, (Hiley: Uhm-hmm.) to David Peat, a very important statement about how deep Bohm was in philosophy, which is very important because itís a professional philosopher making (Hiley: Uhm-hmm. Uhm-hmm.) it. So, itís clear that Bohm, at least in the Ď60s, from the Ď60s on he was very involved in a kind of Hegelian philosophy?

Hiley:

Yeah. Absolutely.

Freire:

And even I read your recent paper I can [Laugh] see this kind of influence. Thesis, antithesis, and so on. (Hiley: Well I. . .) It has not to do with Hegelís influence?

Hiley:

No. No. No. No. No. I donít, I donít mind at all you...

Freire:

Yeah. Talk a little about these kinds of things.

Hiley:

Well, first of all...

Freire:

What influence it had, influence you had in...

Hiley:

From before I met David Bohm, the stories I hear from people who knew him was that he was very into Hegel anyway.

Freire:

In what?

Hiley:

Into Hegel. (Freire: Okay.) And, he used to walk around the campus, now which campus could it have been either Princeton or Berkeley, with Hegel under this arm, and always looking at it. So clearly Hegel, he never quoted Hegel to you, but nevertheless he was very influenced by Hegelís work. Mrs. Bohm told me that not long before he died he was sitting in his armchair at home reading Hegel again, and she said to him, ďDavid, donít you know everything about Hegel by now?Ē [Laughter] So, that was clearly, itís just to show Hegel had a very deep influence in him. I have always felt the reason why I didnít become a pure mathematician was because I enjoyed very much the motivation from more general considerations. You know, Iím not interested in proving theorems, per se. (Freire: Okay. Okay.) While, Iím interested in developing ideas into a more precise way, and hopefully the, you know, theorems will follow from that. So, thereís that sense. And I, in exploring these — you see, if youíre going to do something new in physics where is it going to come from? Itís not going to come from studying physics itself as it is now done, because everybody whoís doing physics now, ninety-nine percent of them are following the tradition that is already laid down. So, where are you going to get your new ideas from? You know, new ideas are going to come from looking at different philosophical frameworks to see if there is anything in those frameworks which is the sort of thing that you can use to develop the way youíre thinking. I found reading Fichte and Schelling very helpful in this, far more so than, than Hegel. Because Hegel I find almost impenetrable. But certainly Schelling — and also a very interesting book by Ilyenkov called ďDialectical LogicĒ that Barros gave me — do you remember Barros? Youíre from Sao Paulo?

Freire:

Barrow?

Hiley:

Barros. (Freire: Yeah.) He was a friend of Mario Schenberg.

Freire:

Yeah. Yes. da Rocha Barros?

Hiley:

Yeah, thatís the man.

Freire:

Yeah. Alberto da Rocha Barros?

Hiley:

Thatís him. Thatís the one. He came here to Birkbeck too.

Freire:

Yeah. In 1990.

Hiley:

1990.

Freire:

Yeah.

Hiley:

And he — was it as late as that? I thought it was earlier but that is the way the memory goes. But he...

Freire:

When he spent almost a year?

Hiley:

Almost a year here. (Freire: Yeah.) He was coming for three months.

Freire:

It was 1990. Yeah. [Hiley was right; indeed Barrosís stay was in the early 1980s]

Hiley:

We had a number of very interesting discussions and then he said he had enjoyed it so much that he spent the whole year here. And it was, it was very enlightening talking to him. I really enjoyed having him around here because he gave me a lot of, a lot of this philosophical structure that I that was not available in the UK. I mean, the UK is not strong in philosophy at all-no, no continental philosophy. [Laughter] Iím going to get into trouble for saying that! No, but you know not the sort of philosophy that appealed to me.

Freire:

You can delete this, after, if you want. [Laughter]

Hiley:

But itís true. Barros really triggered me off to think deeply, to read these guys because they were thinking deeply, particularly Schelling, about the nature of space and time. Kant claimed it is an a priori given. And for me, space and time is not an a priori given, then how the hell can we create new structures that go beyond space and time?

Freire:

Yeah.

Hiley:

So, itís very important to read Schelling to see how he countered Kantís arguments and then how he used this idea of process. I think within that you can see intuitively emerging the dialectic. And then put that together with the discussions I had with David Bohm, with his implicate and explicate order and you can begin to see that the whole structure is such that — and this is what quantum mechanics is telling us. Thatís my feeling. Itís telling us that we need some kind of dialectic. And now, you know, I was at a conference on Category Theory on Wednesday and these guys are just beginning to wake up to the fact that this idea — but theyíre still trying to put it into what David would be calling a ďCartesian category.Ē (Freire: Yeah.) Okay? But, because itís very difficult to actually change the mode of thought and create the mathematics at the same time, too ambitious.

Freire:

Yeah. Yeah sure. But, but thatís the...

Hiley:

In that respect.

Freire:

Yeah. Very interesting. One more question. You spoke the name of da Rocha Barros, so you know that you, itís a question Iím more interested as a Brazilian. You, you had a number of connections with Brazil?

Hiley:

I had a student who did his Ph.D. with me.

Freire:

A student, Marco, Marco Barbosa?

Hiley:

Yeah. Fernandes. Yeah. (Freire: Yeah.) Marco Fernandes.

Freire:

Marco Fernandes, yes. And, you, you considered some of the early works of Mario Schenberg very, very interesting.

Hiley:

His paperís in the Review of the Brazilian Physical Society. (Freire: Yeah.) It had a very profound influence on me.

Freire:

So, about these two or three influence, or these two or three interactions, Schenberg, Marco, and da Rocha Barros, what kind of things can you comment or can you comment or can you, or some, and remember some anecdotes, can you talk?

Hiley:

With Barros it was the philosophical background. (Freire: Okay.) With Marco, he was just coming in and trying to make sense of these ideas himself in the sense of asking me questions and making me think. I had a very good interaction with Marco. (Freire: Okay.) But, with Schenberg, I only met him once in person, either once or twice, no more. But, his papers I had been introduced to now possibly because Bohm mentioned his name, because apparently Bohm thought a lot of Mario Schenberg when he was in Brazil.

Freire:

Yeah. In the final, his final time, at the beginning Schenberg was not there?

Hiley:

Thatís right.

Freire:

But the, I think that in the last year or the one...

Hiley:

Thatís right. No. And, Bohm, I think, told me it wasnít until Mario Schenberg came that he began to get intellectually stimulated again. I think when, when I hear comments like that it makes me do my literature search and I found this paper in Nuovo Cimento of his, and then he referred back to the Reviews of the Brazilian Physical Society. And, those papers I think I spent a long time trying to understand them and wondered why other people did not refer to them — he was developing quantum space times. He was essentially talking about quantum space times. Iíve used a lot of his ideas.

Freire:

Schenberg as a physicist thought that those papers were very difficult to understand.

Hiley:

Difficult?

Freire:

Difficult.

Hiley:

Yes. Yes. Yeah. But, I only like difficult papers. [Laugh]

Freire:

Yeah. Yeah.

Hiley:

I donít like papers you can understand in two minutes. (Freire: Yeah.) There are a lot of rich ideas (in Schenberg). I mean, I learned the fact that heís got the idea of the idempotent in there and these idempotents turned out to be very important to me — Iíve used all these ideas; unmercifully Iíve used them! I think they were, they were, that series of papers was really very important to me — I donít know why other people havenít taken them up. You know, maybe theyíre too difficult but I, but thereís some very stimulating stuff in there.

Freire:

Now, let me ask a different question. Itís about the role of determinism, the role of causality; I mean causality is not equal to determinism. (Hiley: Okay.) I can understand this. Causality is a more general question. But, in the quantum debates usually causality means determinism. So, one thing very intriguing is that if you take your, even your recent papers one can say that your recent papers when you are analyzing the quantum potentials, (Hiley: Uhm-hmm.) yeah, I would say that the idea of well-defined trajectories, well-defined position and momentum are there. And this is the, the very basis of determinism in classical mechanics. Now, the question is, I fully understand that you and Bohm did not emphasize determinism as an asset in the (Hiley: Uhm-hmm.) quantum potential approach. But, this was not the case in the early Ď50s. The very title, Causal Interpretation, which was not a label title (Hiley: Uhm-hmm.) used only by Bohm, the title appeared in otherís papers. But Bohm accepted it and he began to write about the causal interpretation. (Hiley: Uhm-hmm.) One can say that in the early Ď50s the debate about causal interpretation or determinism was an important issue. (Hiley: Yeah. Yeah.) And actually itís clear that Bohm changed a little his mind. One cannot say that you changed your minds because you were not...

Hiley:

I didnít, I didnít (Freire: Yeah.) invent that particular label.

Freire:

Yeah. But, I want to know a little about your own position and also what you can remember about Bohmís own position. And a side question, that this was one of the questions to oppose Bohm and Vigier, you know, on one side, and Rosenfeld on the other side. It was not the only question?

Hiley:

No. No. No.

Freire:

In that order. But so...

Hiley:

But no, I think...

Freire:

Thatís the question.

Hiley:

I have never felt that determinism is something that must be put in at all costs. And, I donít think David, when I met him — donít forget, Iím talking about (Freire: Yeah.) Ď61, plus, (Freire: Okay.) forwards — but he did actually say to me that ďThe reason why I published that paper was not because I was worried about a lack of determinism or the lack of causality in quantum physics. Rather, I was worried because there was no ontology,Ē as we put it now, ďthere was no actual image of the process. There was no actual process that was going on that we could talk about. All we could talk about is what happens at a measurement, at another measurement, at another measurement. But, there was no actuality, (Freire: Yeah.) no way of talking about actuality.Ē And, he said, ďThat was the thing which drove me on, and that was the thing which, when Bohm went to see Einstein, before his papers came out, that was what they were talking about. There was no way to talk about an actuality out there which were independent of our measurements. And thatís what he was, thatís what we were driving towards — thatís where we had a common goal. If that actuality happened to be stochastic or statistical, so be it. But, there has to be an actuality and we have to be able to talk about that actuality without having the observer constantly coming into it. Okay? Now, I have also gone down that road — I think thatís what Einstein felt. He felt he wasnít worried about the lack of determinism. He was really worried about the fact that there was no — okay, so I belabored this point. But that, thatís a very important point, because most people think that Bohm, and maybe myself are determinists and weíre not. Never have been. Okay. Now, now you come back to say, ďBut surely in my latest work Iím putting back determinism?Ē Thatís not true. Because, if you think of this, start with the structure of process idea. Now, in that structure of process idea I have built into it the idea of an implicate order. What we can do from the implicate order? We can project from it into an explicative order. And in the explicate order you can construct trajectories. So, youíre actually constructing your position and your momentum and your trajectories from this deeper order. Youíre not assuming it is there a priori and then generalizing the order. Do you see what Iím trying to drive at?

Freire:

Yeah. Yeah. Yeah.

Hiley:

Now, can I talk about this implicate order, this holomovement? We have the beautiful word of ďholomovement.Ē (Freire: Yeah.) Is the holomovement something which is local or nonlocal? My answer would be, itís neither. Itís a local. Locality is a relationship which we can abstract from this deeper process. And why is it a relationship? Think about the hologram. Here we have something which all the local relations are well defined, but then we can hologram it and weíve still have the local relations, but stored non-locally. So, the relationship of locality is not local. So this deeper process is a local and locality comes when we try to force it into a particular framework. And, thatís the explicate order. So, what Iím saying is, what traditionally science has felt is essential, is only an outward manifestation. And I, I donít think many scientists would agree. I donít think they have grasped, are willing to grasp that, or willing to think about this idea.

Freire:

Okay, let me come back to philosophical issues, but related to, to this point. I have the impression that in your papers, in your recent papers, you have been more explicit. You could criticize the Cartesian philosophy and itís clear that one; one can see that, this criticism even in your earlier papers with Bohm. But, something that intrigued me is that the recent paper, even the expression, Cartesian philosophies, more open criticized more recently? Iím wrong or...

Hiley:

I donít know. In what sense? I hadnít realized Iíd done it consciously. In the early days I had consciously set about contrasting the ideas with the Cartesian order. But, in my latest papers I donít deliberately contrast them. Maybe my thinking has taken a particular road that is non-Cartesian anymore. Would that answer your problem?

Freire:

I think so. I was thinking, for instance, in this 2002 paper, even your recent papers, every time you speak about process, (Hiley: Yes.) you speak that ďwe need to give up the Cartesian philosophy and (Hiley: Uhm-hmm.) to take processes as primary concepts. And this explicit criticism of the Cartesian philosophy, not the idea. The explicit idea was always in your papers?

Hiley:

Oh, yeah, those days.

Freire:

But this, this explicit criticism I donít see in the earlier papers. Maybe when one gets...

Hiley:

Ö

Freire:

You may...

Hiley:

They were in my talks.

Freire:

Yeah. In spots. In spots.

Hiley:

Yeah, but I find it much easier to talk than I do to write.

Freire:

Yeah.

Hiley:

I find writing very difficult.

Freire:

Yeah. Itís possible.

Hiley:

I mean, I donít have a...

Freire:

I need to make a joke. I will say that when you became old you may write philosophical issues in scientific papers, and when you are young you, [Laugh]...

Hiley:

Well, certainly. Certainly this, the censorship is there, because you have to, you have to, you know, have to watch yourself. You know what I mean?

Freire:

Yeah. Now, let me ask one of my last questions. In the recent years there is a huge amount of publication in the activities related to quantum chaos. And, a number of people are very interested in what they call Bobmian Mechanics, in the sense that this could be an approach to quantum chaos. But, it seems to me that you have not been very interested in this kind of research. Am I wrong, orÖ?

Hiley:

Very interested. The problem is that certainly as you get older the amount of energy you have [Laugh] decreases. I have never turned my back on quantum chaos. Iíve always looked at it, thought about it, but have never been able to find anything very sensible to say about it. One of my feelings about why it doesnít appear in quantum mechanics is somehow itís the quantum potential which keeps everything in order and therefore you donít see the chaos. But, that doesnít mean to say that some of the ideas, some of the papers that youíre probably referring to that Iíve been interested in, but they havenít become part of me as it were. Although, I know Iíve got a colleague in University College whoís trying to convince me I should take them more seriously. [Laugh] Iíd say itís the energy problem.

Freire:

Okay. Let me ask a more sociological question. In our lifetime the kind of physics you were devoted since you came to Birkbeck was foundations of quantum mechanics? (Hiley: Uhm-hmm.) So, you have an experience of almost fifty years working in this field and you, you

Hiley:

And I still donít understand quantum mechanics. [Laughter]

Freire:

Yeah, no. But, the sociological question is another, in the Ď60s, in the Ď70s, in the Ď60s at least there were always a lot of prejudice against this field of research. At least, you spoke a lot about (Hiley: Uhm-hmm.) prejudice against the hidden variables, and so on.

Hiley:

Yeah. Yeah. Yeah. Yeah.

Freire:

So, two questions. First of all, what are your impressions about the evolution of this field? And second, what kind of support you had from Birkbeck College during this whole time?

Hiley:

Well when I started working seriously on the Hidden Variable Theory, you know, rather than just — I felt that there was such a compelling case to be made from the mathematics and the ideas that Iíd been playing with that no one would have stopped me working on that. I was hoping that when we first got the trajectories out, I was hoping that putting this in front of an arch Copenhagenist would at least make them scratch their heads and think again. I got the impression that over the years, as more people took part in this, that it was more widely accepted that this was a legitimate way of proceeding and that the old prejudices of Rosenfeld, and Bohr, and Heisenberg, had actually died out. But, I still occasionally find pockets of people who have never bothered to study the subject still prejudiced against it. But, itís a lot better now. And then, but you see now that I sort of — you know, when you become retired you begin to lose touch a little bit about whatís going on everywhere. But, Iíve now noticed that the earlier physics in general is dying. There seems to be, everybodyís putting their money on elementary particle physics, or String Theory, or Loop Theory, but no, very few people seem to be discussing the sort of things we were discussing in the Ď60s, the, just, Iím not talking about the details. Iím talking about the general structure in which oneís looking genuinely to try and revolutionize something. There are exceptions. Chris Isham, for example, at Imperial College, but heís one of the old school. But, itís the youngsters who are not, the youngsters, you know, who are seemingly not because theyíre forced into a difficult job market in academia, they are sort of tailoring their research to what is expected and I think this cannot be but bad for physics in general. Now, the great thing about the research in the Ď60s and the Ď70s was, yes there was prejudice against this but because there was more freedom from the constraint, the university constraints, you know, ďHow many publications? Which journals do you publish your papers in?Ē All this absolute nonsense that has been going on since the Ď80s and Ď90s has now stopped the creativity that we had in the Ď60s. In other words, if your skin was thick enough in the Ď60s not to take any notice of these men who were telling you not to do these things, you could do it. Now days your out!

Freire:

Okay.

Hiley:

Now, Iím beginning to worry, although I say Iím not in the game at the moment, that if you have all these restrictions then people are not going to be able to do as we did in the Ď60s. Iím talking about the bright, gifted youngsters that they are not going to be able to be really creative anymore. I hope Iím wrong, but thatís what Iím seeing. There are some exceptions around the place. But, people in general donít seem to be interested anymore in these questions. I donít know whether this — you know, because to me I donít understand how people cannot, who are physicists who cannot be interested in these questions. You know, they might have different ideas on how to solve them, but itís the interest which seems to be dying. Maybe thatís just because Iím not in the game anymore. Now, did I have any hindrance? I never had any hindrance. The great thing about being at Birkbeck College was that no one told me what I should do and what I shouldnít do. They started to try it, [Laugh] towards the end, [Laugh] but certainly through my entire career Iíve never been told that I should do this and shouldnít do that. So, the college has given me the freedom, and the support (Freire: NowÖ) for which I am very, very grateful.

Freire:

Good. Now, maybe you, you want to make a few comments about the students you, you had here. You spoke about Dewdney, Philippids. (Hiley: Yeah.) About others? One of your collaborators was Frescura, Fabio Frescura.

Hiley:

Okay. Yeah. I mean, please. Iíve had some absolutely magnificent students. But, once again, when you interact with them and when they interact with you itís great, but then they leave. The difficulty has always been in getting positions (Freire: Yeah.) in which they can continue their creative work. Now, you see, in Chris Dewdney I have very high regard when he was with us. He got into a University post but they closed the Physics Department down and heís doing environmental studies. So that all the background that he had has not been, is not being used now. Frescura, really, I owe him a great debt for some of the things heís taught me, particularly on the algebraic side of things. Iím still in touch with him. He has a position in South Africa. Unfortunately, it was a rather tragic situation where he had a chair in Rhodes University but then his mother died and he had to give that up and look after his father and his fatherís business. So, you know, that was sort of a family thing that took him away. But, now heís back again. But again, heís doing astrophysics because thatís the way, where the money is for, for South Africa. Recently, Iíve had some, a couple of absolutely excellent students. Of course, Jeff Bub wasnít my student, but we were really contemporaries. I mean, I got my Ph.D. just before him, but at the beginning we were going down the road of quantum mechanics almost together, as it were.

Freire:

And he, he keeps in the field in a more philosophical side.

Hiley:

Yes. Heís done some really very good work actually.

Freire:

Yes, at the University of Maryland.

Hiley:

Yeah.

Freire:

Yeah.

Hiley:

Yeah. So, I was very happy to go to his sixtieth celebration. They had a (Freire: Oh?) workshop and I was able to give a talk there. Then thereís, two recent guys I had, which was Owen Maroney, who hasnít yet made a name of himself, but heís been at the Perimeter Institute. A very promising young man.

Freire:

In Canada, yeah?

Hiley:

In Canada. Yeah.

Freire:

Okay.

Hiley:

I had an absolute brilliant man called Oliver Cohen. I mean, I think heÖ

Freire:

How is it spelled?

Hiley:

C-O-H-E-N.

Freire:

Okay.

Hiley:

No, E-N. C-O-H-E-N. He was brilliant. He was really, really brilliant. Whenever he knocked at the door and I saw his face, I thought, ďOh no. [Laugh] Iím going to have to think.Ē [Laughter] But, unfortunately, again, because of the financial situation heís now working in some financial institution. And all that, that — I mean he, he published three excellent papers on his own before heíd got his Ph.D. And, I think thatís about the — and one Melvin Brown, but he came to me as a mature student, as a mature student. And he, again, is now working, not in the research field, but as an intermediary between industry and the university. So really the problem has been that they cannot carry on because of the difficulty of getting jobs.

Freire:

Yeah. Okay.

Hiley:

I probably left somebody out and theyíre going to be very angry with me.

Freire:

Yeah. No. No. Yeah, donít worry.

Hiley:

You know, all the research students have contributed in their own way.

Freire:

But, what you spoke about the job crisis in physics and the one interesting thing is that now you have a flourishing field related to the idea of the quantum information. (Hiley: Yes. Yeah.) But it seems that the main driving in this field is related to applications. (Hiley: Uhm-hmm.) So, it seems that foundational issues are a little left aside?

Hiley:

Theyíre not encouraged. (Freire: Yes.) I mean this is, the investigations into it are not encouraged and itís very difficult to, you know, to maintain it. Certainly the quantum information field is big, but then, as you say it is very much technical. Itís very much oriented to whether one could actually use teleportation, could use quantum cryptography, and so on. But still itís going on so we mustnít grumble about it. Thereís an opportunity for people. There is a young man who Iíve come across recently called Bob Coecke, whoís in, was a physicist who was trained with Piron, you know Constantin Piron (Freire: Yeah. Yeah.) you know, and he couldnít get a job in physics but heís working in the Computer Science Department.

Freire:

Oh. And heís, how do you spell his name?

Hiley:

C-O-E-C-K-E.

Freire:

Okay. This is important for the transcription.

Hiley:

Yes. Sure. Sure: Iím not even sure Iím pronouncing his name correctly. But, but he was the one who organized this conference, this workshop on Wednesday at Imperial College. (Freire: Okay.) And he is using some very interesting new ideas on Category Theory in Quantum Theory. In other words, can one describe quantum processes in terms — we need process, we need a description in terms of some natural mathematics. Category Theory depends upon mappings, of process and so on. It seems suited for this. Now, I had a student way back in the Ď70s who came to me and said, ďCould I do a PhD on Quantum Theory and I want to apply Category Theory to it.Ē And I said, ďWell, why are you coming to me? I know nothing about Category Theory?Ē And he said, ďYes, and I know nothing about Quantum Theory, [Laugh] but Iíll do a deal with you.Ē You could never do this nowadays. The student said, ďIíll do a deal with you. Iíll teach you Category Theory if you teach me quantum mechanics.Ē [Laugh] Unfortunately, we both failed, but he got his Ph.D., a very good Ph.D. But he introduced me to the idea that maybe Category Theory is the right approach. Now Iím glad to see that some of our intuitive ideas that we were playing with are now being picked up by other people and doing a lot more with them than we did. So, there are areas where things are still moving, but everybody complains that, you know, they have to do it, (Freire: Okay. Yeah.) you know, I mean in some sort of quiet way.

Freire:

Let me ask a question related to, to influence of philosophical ideas on Bohmís, maybe a sensitive question. Itís well known the kind of relationship that Bohm had with Krishnamurti. (Hiley: Uhm-hmm.) But, one thing is their relationship in more philosophical, mainly a more social manner and so on? Another thing is what kind of influence there was in Bohmís approach coming from Krishnamurti views? (Hiley: Uhm-hmm.) My impression, my impression, I also like to hear from you if Iím not right, my impression is that usually people say that there was more influence than we are able to identify. At the least, almost the main ideas which conformed with this approach we can find in another, another piece that I would say that if you skip, skip out Krishnamurti influence in the very scientific ideas you do not miss anything.

Hiley:

I, no, I think I would agree with you. I think you must remember that, which I think David Peat brought out very nicely in his biography of David Bohm, The Infinite Potential. That is, David was not merely a scientist. He also worried very much about the state of human society and that really did occupy quite a lot of his energy. And, I sort of traced it back, Originally, you see, with the Jewish upbringing he thought that maybe religion would be a way of organizing society, but then the Depression came, and so on and so forth made him say, ďWell, no, thatís not, the pogroms and, you know, all that kind of persecution. Thatís not the way to do it.Ē Then he was hoping that science would be the salvation. The nuclear energy was just coming around the corner. ďIf everybody had electrical energy then everybody would be able to live a better lifestyle,Ē blah, blah, etcetera, etcetera. But, then when he got to Caltech he was very disappointed in the way science was being operated. Doing problems, not really thinking that deeply about problems and society. Then came the political view. Because now in Berkeley in the Ď40s he starts thinking about Marxism, and communism, and fascism, and the interrelation between them and he sort of becomes a little bit excited about communism, but very quickly loses interest in that. And then, I think, the final stage, he thinks maybe the problem is with thought itself, that we have a reptilian brain and a modern cortex and unless we get thoughts sorted out the reptilian brain will always dominate the rational cortex, and so on. And so, obviously this is a huge subject but Iím just trying to encapsulate the ideas as best I can. It was here that I think Krishnamurti came in. (Freire: Okay.) So, Krishnamurti had a very similar type of philosophy, questioning, you know, ďWhy do you need leaders? Why do you need to have authorities? Why donít you work things out for yourself and come into harmony with your neighbors?Ē And then, of course, David introduced the idea of dialog and the idea of dialog was for people to come to a common understanding. Or, idealism, you know, from me as a cynic looking outside and seeing how man behaves, I sort of said, ďWell, who the hell knows what we can do to bring order into this chaos?Ē But, David felt very passionately that he could do something in this area. And thatís where the dialogs with Krishnamurti were so important to him. In a way I was a little bit upset because it took so much of his energy away from what he should be doing, mainly the physics.

Freire:

And Krishnamurti even poses the question of him abandoning science. His...

Hiley:

Oh yes. Yes. Somewhere in that, those discussions, yes.

Freire:

This was probably a very tough question?

Hiley:

Yes. Yeah. Yeah.

Freire:

Yeah.

Hiley:

Well and, but then again he, he sort of fell out of sympathy with that point of view. I think he was a very restless; Bohm was a very restless guy trying to because he felt, and quite rightly I think, he had the intellectual capacity to do things. You know, whereas you and I sort of, well, I donít know about you, but me, I could never organize society, and, you know. [Laugh] And, in fact, I used to try to keep Bohmís feet on the ground, particularly towards the end of his life when his heart was playing up again and he was becoming rather depressed. You know, the situation in the world was getting worse and worse, with Saddam Hussein. And, he really got so obsessed with all this. Somehow he was taking all these problems on his shoulders. That, because his ideas had failed, therefore Saddam Hussein — of course, it was total craziness. But anyway, I think that thatís where the Krishnamurti (Freire: Okay.) influence came.

Freire:

Itís a very interesting because it is exactly what I had been thinking about this, (Hiley: Uhm-hmm.) kind of influence.

Hiley:

And I often — well, can I just — I often wonder whether it was because the Bohms never had a family and they used to be trustees to the Krishnamurti School down in Brockwood Park (near Alton in Hampshire, England), and I often felt that maybe this was their family. But there again I say, and then the whole thing went sour again. But, so I donít think it, I donít think that that influenced his physics significantly.

Freire:

Okay. So, my list of questions is over.

Hiley:

Oh.

Freire:

But, I would like to know if there is anything else that you could, you want to keep on the record. You have time to include anything. But if you nowÖ

Hiley:

No. I think youíve done a very good job in picking out the really important areas in the development of the ideas.

Freire:

Okay.

Hiley:

And weíve been going for several hours now.

Freire:

Yeah. [Laugh] Uh huh.

Hiley:

But I hope thereís something interesting.

Freire:

Yeah. Very, very... END OF INTERVIEW.

After the interview, Olival Freire asked to Basil Hiley about the role played by the notion of ďchaosĒ in the work he had developed with David Bohm. Hileyís answer may be seen as a complement to the interview. It is described below. [...] You ask the role of chaos theory in our discussions. There were two aspects of this question in our discussions. Firstly we wrote one or two papers on what we called the Ďstochasticí interpretation (Phys. Reports 172, (1989), 93-122). That was mainly inspired by the work of Nelson, but also went back to the early work of Furth who was a Reader of Physics at BBK before Bohm took the Chair. This was not Ďchaosí in terms of the fashion that developed in the 70s, but rather of the de Brogue variety which assumes some form of stochastic Ďsub-quantum mediumí. The second aspect of our discussions saw Ďchaosí in terms of order. For Bohm every order was an order: for example Ďdisorderí was also an order. If I remember correctly, this idea has its roots in the Schutzer paper. I canít check it because I canít lay my hands on the paper at the moment. The work on chaos that we found most useful was the ideas contained in Mandelbrotís book ďThe fractal geometry of NatureĒ, because there we see these ideas discussed in terms of the notion of Ďorderí. One of the criticisms I made privatively of the implicate order was that the way we were using it; we were simply keeping the same order but simply unfolding it in a different representation. In effect nothing was actually happening. The unitary transformation was simply a re-description of the structure. What was needed was a more general generative order, an order was new forms were created and destroyed. This would take QT out of the class of mechanical orders, into that of an organic order. Wasnít it Schelling who hoped that the antinomy between mechanism and organism could be resolved by introducing some truly universal principle that would unite both seemingly contradictory notions as different aspects of the same whole dynamical process? Bohm hoped to see the resolution of the conflict in terms of order. Nature was not either mechanical and deterministic or chaotic and in deterministic. It was a dynamical whole with mechanical orders and organic orders existing together in one unifying order. That unification would be, in the first instance, the implicate order, but more generally in the generative order. The best place to see this discussed is in his book with Peat, ďScience, Order and CreativityĒ chapters 3 and 4. It was a great pity that Rosenfeld got Ďon his high horseí, because if he had listened carefully to what Bohm was saying he would have seen the common ground that they both shared. Perhaps I should have said Ďread more carefullyí because, I believe, he reviewed ďCausality and ChanceĒ. If he had read it sympathetically he would have seen that Bohm was moving to a deeper understanding of complementarity through a kind of dialectic order. In other words Ďcomplementarityí has itís origins in ontology, not in epistemology, a mere inability of us humans to describe quantum processes. This is the way we are taught in physics, it is the way it is expressed in the text books. The phrase Ďwave-particle dualityí is confusing nonsense. In the book, Bohm discusses the qualitative infinity of Nature from which processes unfold; that is where things that appear Ďcontradictoryí can be united. The papers with Carmi were really technical papers continuing his line of investigations into plasmas. What his earlier work with Gross and Pines had discovered was that the plasma contained an oscillatory collective motion emerging from what looked like a chaotic background of individual particle motions. Here they were not using the modern notion of chaos. Rather the underlying movements of the particles could well be following the laws of classical mechanics, but the collection of initial conditions for the particles was some random set. If there were some symmetry in the system then this is revealed in what one calls Ďcollectiveí movements described by some suitable form of Ďcollective co-ordinatesí. These can then be used to form a phase space which will provide an approximate description of the plasma dynamics. Although you can generalize these ideas to provide a general model that could underlie quantum processes, these two papers did not go down that road.