Volke ran a theory group at the University of Cambridge for many years, and his response to the themes in the book, and conferences, is below:
1. ‘Scientific Revolutions’
I have been much impressed by Karl Popper’s book on ‘Scientific Revolutions’, either in ideas as he recognised or more often through new technology such as the microscope or telescope.
Of course all my career has been involved with one such revolution, the use of computing. When I arrived in 1954 from New Zealand to do my PhD, I used the EDSAC 1, which I believe was the first modern computer in 1948 in the world where the instructions are stored digitally similar to the numbers (with very important consequences)
When as an M.Sc. student in New Zealand I said to my professor that I wanted to do theoretical physics because I was better with maths than with a soldering iron, he said “You can’t. It only takes the Einstein’s and Fermi’s of the world ten minutes to have an idea, and there is not any real *job* for a young person to do.” and indeed before my first appointment in the Cavendish I had to demonstrate that I could demonstrate (!) and much of the Second Year optics Lab stems from me. But of course that all changed when computing made it possible to relate theory much more closely to experiment.
I have been a bit involved with another revolution.
In 1960 it had begun to be possible (at the General Electric Research Labs) to make a vacuum so good, by baking out the apparatus etc., that one could keep a surface atomically clean for long enough (an hour) to do an experiment on it. I attended the first informal meeting of interested physicists because I happened to be visiting (‘consulting’) at GE at the time and because they could not find any theorist in the field.
Yes, two important lines of research resulted from that.
With my graduate students, I say ‘Yes’ one should keep asking deep and wide questions, and ferret out what really advances a wider understanding in a field, but that does not come with just sitting and contemplating, or pining after being the next Nobel Prize winner. It is important also to keep doing the ‘normal science’ opened up by a ‘scientific revolution’.
When a new door has been opened, jump to it and walk through it!
I used to do quite a lot of thinking and analysing, and once gave a talk on ‘Ten breakthroughs that I missed seeing!’ in my field of expertise. It is incredibly difficult to think a thought that no-one in the world has ever thought before, or rather that one has never heard before. In each of these examples, I had thought about wherein the problem really lay and the basic principles, but simply missed seeing the answer. Of course it was all obvious as soon as someone else did, and that sometimes enabled me to make use of it instantly.
2. Models
A hunk of material, and all the electron making up a solid and all repelling one another, are very complicated systems, and we always necessarily deal with simplified models. Indeed that is part of what is meant by ‘understanding’. Einstein once said “The best model is the simplest model, as long as it is not too simple” as I have often quoted to graduate students.
If I want to explain what an anti-cyclone or a cold front is in the weather, I would draw a circle or straight line, with other simplifications to give some indication of the physical principles that give rise to such weather features. But if I was being paid to forecast the weather for the farmers, I would have to put in every little bit of detail that I could. Of course one’s understanding would also go into the computer codes for the forecasting.
So choosing the right model is important to really advance understanding.
3. Computational Physics
I often describe our computational physics as ‘computer experiments’. If one believes in the laws of physics, then a computational simulation should give the same answer as the same experiment on the laboratory bench. I have had a lot of flack from experimentalists on that. Of course there are idealisations in simulations (see re models above), and we have to validate the computational approximations, just as some experimentalists using ultra-pure materials in ultra high vacuum have to validate their methodolgy. E.g. how do they know their surface really is atomically clean?
I have sometimes used a nice engineering example in semi-public talks. Do you know the complex junction at the top of Victoria Rd and Histon Rd where they meet Huntingdon Road, and where also Mount Pleasant Rd comes in, making it a 5-way junction with two offsets? It used to be chaotic, with one or even two policemen on duty at rush hours. And then they installed traffic lights. And people said “They will never work.” But the very first day that they were switched on, the traffic flowed more speedily than with the policemen! And the timing of the lights was different during the morning and afternoon rushes, and maybe other times of the day. I think someone must have done a first-class job of computer simulation. Certainly there had been little strips on the roads counting how many vehicles werre arriving and leaving in each of the 5 directions.
Conclusion: computer simulation is now part of experimental physics!
4. Carrying the ideas
I think it has been true throughout the 20th century and beyond, and maybe earlier, that it has been theoreticians who have mostly been the ones to travel and spread the latest ideas. E.g. you can see their numbers being out of proportion in the photos of the famous early Solvay Congresses.
Part of the reason is that experiments are much more time consuming than theory (as I learnt in my Masters thesis in New Zealand, when the damned crystal that I was supposed to be researching on damn well didn’t want to grow!). And of course theoreticians are supposed to understand things! I can remember once attending a conference in the early days when I never attended a single talk!! I was sitting the whole time in the corridor, with experimentalists saying to me “I have done such and such measurements, and think about the results as follows. Does that make sense?” When I was young, quantum mechanics was still a mystery, with the wave equation being applied on Mondays, Wednesdays and Fridays, and Heisenberg matrix mechanics on the other days!!
5. Travel, conferencing and talking
I have a mind that wants to run along a narrow deep track, and finds it incredibly hard to absorb a load of information. Hence reading the literature has never been important in my life. I always travelled to conferences and as visiting scientist, and had a very active visitor programme in Cambridge, from which I learnt the latest ideas. In a talk, people come quickly to the main point that they want to get across, and one can ask them questions to elucitate more.
These visitors incidentally often interacted also with other groups in the Cavendish, which I sometimes had to point out when people pissed on the TCM group — “computation isn’t ‘real’ theory” and anyway “the Cavendish is the Department of Experimental Physics”.
6. Excellence in research
Nevill Mott (Sir Nevill, Cavendish Professor 1954 on) once said to me:
“There is a great deal of research in British universities which is very important for keeping staff and students intellectually alive, but its contribution to the furtherance of knowledge is practically zero.”
In many areas of physics, the research front is quite a narrow region, between research that is not yet do-able for lack of technology or ideas on the one side, and what has already been done on the other side. And if one isn’t already at the research fron, then one is not going to be pushing it forward.
See also items 1 and 7.
In some fields such as biology after the realisation of the Double Helix, there were bags and bags of projects that were worthwhile and do-able. That was a breakthrough that ushered in a huge flood, and of course anything related to medicine is by definition worthwhile.
7. Cooperation in Europe and elsewhere
You might think that cooperation would come naturally to scientist, most of whom have had PhD or post-doc or whatever experience in other countries than their own home. But when anything to do with money or prestige or ways of doing things arise, then nationalism can break out all over them like boils (!), the same as with other people.
At the end of the 1970s there was one of those ‘revolutions’ in my field of quantum mechanical simulation of materials. I can count three theoretical breakthroughs, and the advent of the first (Cray) supercomputers. Moreover EPSRC had the foresight to buy a Cray 1S for Daresbury, specifically for the general scientific community in UK as a whole, and this was the first machine on this side of the Atlantic available for the general scientific community in universities etc. to use.
In Europe there were 5 young scientists spread across four countries who had brought this methodology back from some time spent in USA, one of them in a New Blood post in my group selected by EPSRC. So there was very strong pressure to produce results! Before that, there had been a tradition of individualism, with everyone writing their own computer code and generating their own pseudopotentials etc. etc…
But it was obvious to me, and I told them so, that they did not have the slightest chance of doing world-class work (see item 7 above) if they followed that ‘go it alone’ way. I organised a half-day meeting at the end of a conference in January 1982 to which about a dozen people came, and we started the ‘TE&F Club’ with an annual workshop starting in 1984 atracting
100 to 300 participants, including a few leading people from USA and the Far East. That still continues. [Never mind what the initials TE&F stand for or rather stood for: they have now largely been dropped, lost in history.]
This TE&F Club just wanted to run these annual workshops with minimal organisation, but around 1992 there was an opportunity to form a European Network called Psi-k funded by Brussels with money for workshops, working groups, conferences, training, travel for graduate students as well as researchers, and a Psi-k Newsletter. It was later extended for three more rounds of 5 years each by the European Science Foundation, and still continues funded solely by its members.
**** The punchline is that this cooperation has made Europe the leading area in the world for this kind of computational and theoretical physics and now materials science.
**For me, what is equally important is the spirit of community established by Psi-k and the contribution it has made to many lives.
Let me elaborate. Psi-k was based on three principles, which for me encapsulate the Quaker way of doing business transferred to a secular setting.
(a) Scientific quality matters more than anything else such as money, prestige or group size, in all aspects of its activities regarding for example the location and invited speakers at conferences. This has been an absolute principle to which everyone has been committed. [And one person who was clearly not committed to it left the network.] Of course we all understand that at the end of the day national funding agencies etc. expect there to be a reasonable spread of countries represented, and we wanted that too as part of our Network’s commitment to each other, but it is never allowed to enter specific choices. Incidentally, in order to be at the leading edge of research, we maintain active exchange with our friends in USA, Japan and now elsewhere.
(b) The network is committed to try to serve everyone in our research community, not just leading people or large groups. We specifically reach out, especially in the early days, to isolated workers in small or isolated institutions by having a series of Working Groups on specific sub-areas such as application to magnetism or minerals or surface science, to which anyone in the network could join. There was never any formal membership of Psi-k: anyone is free to join in.
(c) We are committed to create opportunities and support for young researchers entering our field. This was especially important in the early days when our type of work only existed in a handful of places across Europe. As a result, our research groups are incredibly international.
This principle finds expression in all sorts of ways, including a little V.H. Prize every 2.5 years for a Young Researcher with half-hour invited talks at a major European conference for the five finalists which will look good on their CV.
***As I said, these principles express for me my Quaker principles and a contribution to peace making in Europe. Critical is the absolute commitment to the principle in (a).
Volke Heine
I was wondering how this book would be received by professional social scientists, and the first answer is out. A review from Jonathan Adams in Nature (May 2016, here) seems to find it an interesting project and a “refreshing description”. He really appreciates the need to find better ways to help evolve the careers in science, and new opportunities it opens. It’s nice to see he enjoyed reading it, even though it intersects so directly with his professional research space.