Interview transcript

Professor, I want to say thank you very much for coming to this interview today.

Norman F. Ramsey: Happy to be here.

I would like to start off by asking you, you are now in your 90s and you’re still working, I believe.

Norman F. Ramsey: I’m almost in my 90s. I will be 90 in about two months.

That’s fantastic. And you’re still working?

Norman F. Ramsey: Yes, still work some, but I work less than I did before. And I’m much slower than I was before.

Why do you want to continue?

Norman F. Ramsey: Because it’s very interesting. I want to know the answers. We’re trying to make various investigations. We’re studying symmetry of the neutron and looking for an electric dipole moment to the extent to which it may or may not be shaped like an American football or like a sphere. And it’s a very interesting thing; I want to know. And we in theory have been sort of competing on those theories of whether there should be one there, or shouldn’t be one there. Now we’re convinced that there should be one there, but we haven’t seen it yet. But that’s a puzzle for them.

That’s fantastic. The people you’re working with, are they former students of yours?

Norman F. Ramsey: Yes, some are former students. I’ve been working particularly with a somewhat international group at Grenoble, France. I would say Michael Pendlebury is one of the principle and Philip Harris and some of the people from Grenoble. I started the experiments with graduate students.

Is it so in your field that you, as you said ‘We don’t know the answers to certain things and I want to know them’. You have … is it like almost building a puzzle?

Norman F. Ramsey: That’s right.

Is it that you pick up some information?

Norman F. Ramsey: That’s right. I mean the very first experiment I did and that was looking disparity, which is symmetry, whether nature would know the difference between left and right handed. And everybody said ‘It won’t know the difference’. But I said ‘Well, it’s still worth doing a test’. We didn’t find it, but it turns out there was a failure of parity. That’s a good test to do.

What was it in your childhood maybe that made you want to become a scientist?

… physical things have always interested me. I was curious and still am.

Norman F. Ramsey: I don’t know. I mean at the time I was a child I didn’t know too much about science is a thing you, a career you go in to, but on the other hand one of my favourite magazines was Popular Mechanics. And I used to make up some of the things that they did there and read with interest what was then the frontier of science as it was then reported. And it fascinated me, but at the time I was in college, even physics wasn’t really recognised as a subject, so it was only after I graduated from college that I shifted to physics actually as opposed … well for a while I was in mathematics, which I enjoyed very much. But it was always, my basic interest was always there. I mean physical things have always interested me. I was curious and still am.

Interviewer What do you think when you were rewarded the Nobel Prize, 1989, had you expected it?

Norman F. Ramsey: No.

No.

Norman F. Ramsey: No I had not. Almost every year a group of us would wonder not whether I’m going to get the prize, but whether who’s going to get the prize. But that particular year 1989 my wife and I had been on a mountain trip in the Himalayas. We took a trip from Kashmir to Ladakh passing over a couple of passes at 17,000 feet high, which was higher than any mountain I’d been On, much less any pass, and it was a fascinating trip. We didn’t speculate about the prize from here. I got back home and even then I had a little bit of learning about it because we’d been away the previous year actually visiting a professor. And we kept the telephone, but it was turned out this company only kept the telephone in my wife’s name not my name. So the chairman of the committee couldn’t find me.

How long a time did it take?

But I learned later that they had even made a mistake. …

Norman F. Ramsey: They released it to the newspapers at seven and the New York Times science editor found me immediately. I mean he knew where I was. But I learned later that they had even made a mistake. They had guessed maybe I might be in Washington DC. There was a Norman Ramsey there. And the chairman of the committee called him and called that number and asked if the young man who answered it his father was there. And he said ‘Yes he is’. ‘Well we’d like to speak to him’. He said ‘But well my father’s sound asleep. It’s now six a.m.’ and they said ‘We want to tell him he’s received half the Nobel Prize in Physics’. And this young man said ‘That’s very interesting since my father’s an economist’.

You never got to speak to him about that?

Norman F. Ramsey: I’ve been meaning some time when I’m in Washington, look him up on the phone register and say ‘Yeah, I’m glad you didn’t steal my prize’.

So what was the feeling then when you got it? Were you really happy?

Norman F. Ramsey: I was delighted. My first reaction even after I got the call from the New York Times, my first questioning was, he told me ‘What do you think about getting half the Nobel Prize in Physics’. I said ‘That’s wonderful, but are you sure?’ But then he named the other people who were getting it that year and they were very good. I was delighted to be in their company and that made it sound as if it was a real thing.

Your discovery has had many implications.

Norman F. Ramsey: Yes, it has.

Could you tell us a little bit about you know what is has been and what you see in the future?

Norman F. Ramsey: It has had really many, many more than I would have expected at the time I was doing the work, which was work on magnetic resonance. Magnetic resonance was a brand new thing before even I did the work because before I received the prize I was working with I I Rabi at Columbia. And had the very good luck of starting to work with him about two months before he invented the magnetic resonance method, which was a new thing. Immediately I and several others started working on it and the first experiments worked. Then the second experiment didn’t really seem to work right and you know you’re always disappointed when it doesn’t work right. But usually that’s more exciting because then it means there’s something different we found. Yes we were also looking to interactions in molecules, which was not what we were looking for originally. And so in addition to measuring the magnetic moment of the nucleus, we were also measuring the interactions that was in the molecules. So the chemists were almost immediately very interested in it.

And since then it has steadily expanded other things, part of which I have been involved in and part of which other people have been involved in. I mean one of the ones that turned out, because of the interaction in the molecule, particularly in the case of Adams, it’s a very sort of constant of nature. And it’s determined by quantum mechanics; it’s a very interesting thing. Quantum mechanics has things are fixed. You can be sure what they are. So quantum mechanically you could be sure that this constant would stay fixed, for that mean measuring that is a very good basis for atomic clocks because you need for that, and it’s really even different in principle for more previous clocks. I mean previous clocks like pendulum clocks; it depends on the mechanic who makes the pendulum. Does he make it the right length?

And in the case of atomic clocks, it’s nature who makes the device that determines the time, so that it’s universally you can be sure, unless we make a terrible mistake. If we make an atomic clock in the United States and someone makes it in England, it better be the same within our experimental area. And then we’ve steadily improved it. So that turned out, it makes that time determine that way rather more fun in the middle you know. And secondly it also is true that you could measure it much more accurately. So it’s both happy circumstance that the most accurate measurement, so that for example the second, the unitive time of the second is now determined, is defined in terms of oscillation and a caesium atom, which we were concerned with at one time.

It looks as there will be even better definitions of a second …

I think it’s a rapidly moving field now. It looks as there will be even better definitions of a second. That atom was accurate to about what we call one part in 10 to the 15th. That’s one part in one followed by 15 zeros. So it’s very accurate. But there are things for which you need even greater accuracy. It’s the best test of the theory of relativity are now done with atomic clocks. And you can make extreme tests for that. Radio astronomy is now a very powerful tool, but to make the telescopes have good resolution, you want one to be in one side of the earth and the other on the other side of the earth. But you have to have good clocks to match the two. So there are many, many applications for it.

And GPS is another area?

Norman F. Ramsey: What?

GPS is another area?

Norman F. Ramsey: GPS, everybody who buys for $100 a GPS receiver doesn’t actually get an atomic clock. He gets a good crystal clock. But the satellites which are going around which give the signals that he synchronises to, those are atomic clocks. And then particularly the central stations, which keep the time for the whole system, are atomic clocks.

It’s fantastic because it’s really helpful. I mean it helps a lot of people.

Norman F. Ramsey: Oh it’s very helpful. In fact, the talk I was giving here yesterday, I was talking about, since this year is one of the specializes in sort of applications to other fields and interdisciplinary things, I chose what about the different ways in which magnetic resonance, which we started this one narrow area of just measuring the magnetic moments of the nuclear. Well which I mentioned extended quickly to molecules, then extended to atomic clocks. And then was extended to NMR, which is a way of we looked at our regional things. We only looked at atoms in a beam by themselves, but you can also detect magnetic resonance in a solid, or gas or a liquid. And that extends what it can be done on and to make very sensitive measurements there.

… you get these beautiful pictures of a person’s brain …

And then of course there’s this really revolutionary development many years later. Well I mean that’s really coming strong in the last few years, which is magnetic resonance images, MRIs. I mean there’s a great increase in the power of it because it enables all of our earlier magnetic resonance and also NMR had the characteristic that you only looked at a whole, all of a sample. With magnetic resonance imaging you can look at a big sample, but tell which part gives what picture, so you get these beautiful pictures of a person’s brain. And they can even detect when you’re, if you’re asked a hard question, they can see, they can do some things to determine what part of your brain is doing your thinking.

That’s amazing.

Norman F. Ramsey: It is amazing. So that’s a totally different atom. That never entered our mind, but of course in medicine, in medical research and medical treatment, this is a key thing.

It’s revolutionary because we could detect so many things much earlier I would imagine…

Norman F. Ramsey: Yes. That’s right. That’s correct. And there’s a certain amount of good luck doing research. I would say that’s one, at the time I started the research and better and better with it of doing more accurate magnetic resonance, which is what the prize was for, it was obviously a very important field. But it became a much more important field later and it’s sort of nice to see your things leading to that.

That must be so rewarding.

Norman F. Ramsey: Yes that’s very rewarding.

Maybe that’s one of, as you said, you know the reason you’re still so curious, is that what you need to have, the curiosity?

Norman F. Ramsey: That’s right. You need to be very curious and willing to work hard, but also think freshly I mean.

During these days in Lindau, we are meeting in Lindau for this interview, you meet a lot of young people.

Norman F. Ramsey: Yes we do, and that is a good thing, I think very good thing for the young people. It’s also a very good thing for us because it renews us as well as them because we see these fresh minds. A meeting yesterday, we had about ¾ of an hour talk and then they open it to questions and they ask very good questions really.

What do they ask you?

Norman F. Ramsey: Oh they asked all sorts of things ranging all the way from technical things as to exactly how the resonance worked to what I thought were good fields for research in the future. They get really very freewheeling, what I thought of research. And even had some questions on disappointments, what if something doesn’t work?

What are you doing then if something doesn’t work?

… what happens after you’ve had one of your failures?

Norman F. Ramsey: That’s one of the things I talked about. I think all of us who do scientific research, almost all of us have our successes and our failures. And the key difference between the people I think who on the whole succeed and the others is what happens after you’ve had one of your failures? I mean you think you have a good thing, an important thing to look for and well it can’t be there; it isn’t there, you can’t find it. It’s a disappointment. Or somebody else does the experiment first, that’s a sad thing too. But the people who are really good in the field, say ‘Fine, I guess we lost that one. We’ll try something different we hope that’s even better’.

So the scope for doing new beautiful discoveries are still out there obviously?

Norman F. Ramsey: They’re still out there. They will be different in nature. I mean yes, no one will ever discover again that at least in the energy levels we’re doing with if the electrons circulate around a nucleus or something like that. That was done by our people, but how it does it? For example, when I decided to do experiments of Rutherford and others who found that was the motion. It wasn’t quantise. Now we know that you have to do with quantum mechanics. It’s probably different mechanics in fact and that’s developed in more recent years. And we have the interesting time I think in physics now that in some respects we can account for an amazing amount of material. I mean our ordinary universe that we see at normal energies, at normal accuracies, we really understand quite thoroughly. And it requires quantum mechanics to do this, but it works.

That’s fascinating. My last question would be, do you believe that scientists have any special responsibility, particularly scientists who have received a Nobel Prize, for bringing messages of importance to politicians and decision makers?

Norman F. Ramsey: I think they do and I agree with you that probably specially Nobel Prize, a number of us do that. Unfortunately, sometimes they are not so responsive and I am afraid at the present moment our government is not as responsive as it was a few years ago, but I hope that will change. But I still think it’s still important to do. This is true for example the things on the environment. I mean it’s very clear that the atmosphere is heating up and that at least a significant factor of that is due to people. The problem of CO₂ in the atmosphere is important, but some of the officials in our government don’t recognise it. So even though they have scientific committees that call this to attention and say it is something we should do, and somehow they sort of get some other advisers. The trouble is you can always hire somebody who can give you advice in a different direction if you want. And then they tend to modify their reports in that direction. So there are real problems in that regard. But the answer is yes, we should and I have. I mean actually in my case I also felt very strongly about not getting involved in the Iraq war, but that didn’t affect the government’s position.

Thank you so very much professor.

Norman F. Ramsey: Well, you’re very welcome.

It was very nice to meet you.

Norman F. Ramsey: Very nice meeting you.

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