2 of 4
How did you come to move from pure mathematics into physics?
That came about because physics was in a golden age during the late thirties and forties so that it was obviously very exciting stuff. I re member reading physics books in the evenings during the later years of World War II, when I was working as a statistician for the Air Force, and that's probably when I settled on physics. I already had a degree in mathematics. I was probably 22 or 23 at the time.
The main contribution you have made to physics, or at least what you are best known for, is quantum electrodynamics. Tell us a bit about how you first got interested in that.
That was the central problem in what we now call particle physics, which in those days was called atomic physics. Quantum theory had been formulated around 1930 by Heisenberg and Dirac and had been widely accepted. The theory looked good and agreed with the experiments more or less. But in the forties, it was possible to do more accurate experiments, which showed that the theory didn't precisely agree with the energy levels of the hydrogen atom. So, it was a problem that everybody saw as a central problem to "clean up this theory" and find out what was wrong with it. That's essentially what I did.
The solution was a combination of many factors coming together. There were new theories produced by Julian Schwinger, Richard Feynman, and Sinitiro Tomanaga, all of them pointing the way to getting the right answers. In fact they all managed to get the right answers, but the mathematics was still a mess. So, as a mathematician I came to it then with the right tools. But I didn't contribute anything to the ideas, I just contributed mathematical technique to clean up the mess and make the theories usable.
You have worked with a number of extraordinary physicists. Among those figures and their immediate predecessors, is there one you think of as the greatest physicist of the twentieth century?
No, I don't think that sort of ranking makes much sense. You can't really compare people with different kinds of personalities. It's just a question of taste. I suppose if I had to choose some body I found congenial to my taste, it would be Rutherford. There's a famous story of Rutherford complaining to Eddington, "Why is Einstein so famous? After all, I found the facts of nature, which he is only trying to explain." Anyway, it's clear that Rutherford and Einstein were the two big people. Rutherford was the more sympathetic to me. It's true he worked in the laboratory and built tools while Einstein was playing around with ideas. Those are the two major themes of science, tools and ideas. But I find that in a way the more fundamental contributions very often come from tools.
You're well known for your belief that science should serve the greater good, and, unlike some scientists, you're motivated by more than the fact that science is simply very interesting. Can you comment on the source of your passion in this area?
I would say that you shouldn't overstate that. When I'm doing science, what I'm actually working on professionally has nothing to do with the welfare of mankind at all. I never think of it in those terms. I have two quite separate modes of living. As a scientist I'm interested in the puzzles. Whether they have anything to do with practical matters or not, I work on puzzles because they're fun to solve. As a citizen I'm concerned about the human aspects, but there's not much connection between religion and my own work, there's nothing at all. I can't claim as a scientist that I did anything that was much value to humanity.
share this page
RSS Feed
