Wednesday, July 25, 2012

Douglas Dean Osheroff: We have to stop burning fossil fuels

The Nobel Prize laureate, an American physicist Douglas Dean Osheroff recently visited Slovakia – a country of his grand parents. During a very tigh schedule he found a little bit of time and shared with us his views about the future of energy, how his life changed after co-discovery of superfluidity in Helium-3 and his memories of Richard Feynman. 


Mr. Osheroff, the origins of your mother are apparently connected with Slovakia. Were you interested in your roots?

My grandfather on mother's side was a Lutheran minister. I really don't know much about when they came to the United States but my mother was one of 5 children. It's sort of interesting, four girls and boy. And she had a family of four boys and a girl. I'd never actually knew much about origins of family and when they came to USA. So I'm afraid I'm rather ignorant. Except when I was invited to Slovakia, to the country of my mother's roots.

So this is your second visit of Slovakia. Did you have a feeling to trace your possible family here?

I don't know anyone here that was at all connected to my grand parents. I know a few control phrases from my mother when I was young like „Daj to preč!“ ("Put it away") , „Zavri dvere!“ (Shut the door) or „Poďme spať!“ ("Let´s go to bed").

One time I was working with junior graduate student at the Cornell University. This was just after discovery of superfluidity in liquid helium-3. This guy was Willy and we were eorking until late hours. It could be probably about 2:33 AM. I turned to him and I said: „Willy, poďme spať!“. He looked at me and said, did you know what that means? I said, it means it's time for bed. He said no, it means let's go to bed. So for mother let's go to bed means a very different thing than for me to say to a colleague.

Another word I know is „poriadok“ (order). She would say "poďme robiť poriadok" (let's make some order).

In retrospect, how did you become so fascinated by science?

I think it was really my father. I was five years old and I got an electric train for Christmas. My father was a medical doctor so he was usually up late. So my parents would take a nap in the afternoon. When they got up from their nap I've take my locomotive apart to get electric motor out. And I think this was a kind of watershed event. I think my father actually wanted to go to become a scientist but it was during the Great Depression. His father probably said, well if you go into chemistry, you would get the Master's degree and you want to get a PhD. So if you go into chemistry, you may never get a job. Whereas when you go to medicine you always have a job. So he went into medical school.

And then, well it just kept building things. He had a patient that worked for the telephone company and they were permanently changing their offices. I got lots of boxes with junk from the telephone company. At one point my father gave me the ignition coil from a car (it is the thing that generates spark and sparkplug that causes the mixture of fuel and oxygene to explode). Back in those days, car batteries were 6 V not 12 V so you put in 6 V and you get out 2000 V. So I said wow, what happens if I put 600 Volts. I have all these capacitors from the telephone company. I kind of wired these things all in parallel. I had a brother who was ham radio operator and I borrowed one of his transformers and I bought two rectifiers. So I charged these capacitors up to 600 Volts and then discharged that across the primary for the spark well for the car. These things were absolutely lethal I think. Luckily I didn't kill myself.

In 1996 you shared Nobel Prize in Physics for co-discovery of superfluidity in Helium-3 along with David Lee and Robert Richardson. Looking back, was the Nobel Prize for you personally a blessing or curse?

I think - both. So what happens is I was really happy to do the research and suddenly you get the Nobel prize and it opens a lot of doors. Lot of these things were really fascinating or things I felt I would like to do. So you have much less time and you're not thinking about your research. You're thinking about all of these global issues like global warming and stuff like that. So it really changed my focus a lot. So this was in 1996 and I was already at Stanford University. My research productivity started dropping off. That time I knew what happens but I was so fascinated with all of the issues and all of the opportunities that I got to work as Nobel laureate. I don't think that I made a conscious decision to basically to wind up my research but that's what happened.

As far as I remember, Richar Feynman said something very similar as you. Incidentally you used to attend his lectures at The California Institute of Technology (Caltech). Do you have fond memories of him?

I'm an experimenter and Richard Feynman was a theorist. I think he was probably the first modern day scientist to get Nobel Prize. Or maybe not but he was very outspoken. I'm little bit outspoken too. Feymann developed these Feymann lectures on physics and every undergraduate student at Caltech (The California Institute of Technology) had to take 2 years of Feynman physics. Feynman gave a few of the lectures and by time I was a student mostly the lectures were being given by people that actually created the book Feynman lectures in physics. Certainly Feynman set the tone of how we were studying physics.

I would tell you that my freshman class at Caltech there were 192 students but only 120 returned for their sophomore year. So almost the third dropped out. I think that was largely to the Richard Feynman. Not that he wasn't a good teacher but he was asking too much of lot of the students. 

I was being offered a faculty position at Caltech and I was very loath to accept because Caltech was very challenging for me. I mean I did pretty well I think but first time had a real work in my life was at Caltech. I was visiting one day and these guys were trying to get me agree to join a faculty. I should pay my respects to Feynman. Everyone knew he had a stomach cancer that time and he'd already been on Challenger investigation board and everything like that. So I would go to his secretary. Her main job in life was to keep people like me away from her boss. I was arguing with her and then Feynman comes out and I said who I am and hey says: „I know who you are! For God's sake we're trying to emply here!“.

Then we went in to his office and started talking about all sort of different things and lots of physics in it. And then I invited him to visit Bell laboratories. First he said: „I can't do that“ because his daughter wanted to go to Cornell University. I said if you are going to Cornell which is in Ithaca, you have to pass trrough New York airport. It's only 20 minutes drive from Bell Laboratories. I persuad him of one day visit. I agreed to take care of his daughter who was mostly interested in horses.

It was fascinating. I mean Feynman is certainly his own person and no one controled him. So he came to Bell Laboratories and we had this auditorium and he was supposed to give a talk there. I didn't know what talk is gonna be there but it was about reversible computers. Any process that is reversible has to happen slowly. Otherwise it won't be reversible. It's like if you drop something on the ground, that's irreversible process. Anyway I was listening to this talk and said why we just don't talk about physics. Auditorium was totally full. If the fire marshalls have come in, they would have kicked us all out because of too many people. All of the isles were blocked with people everywhere. So he talks for about 45 minutes and he opens it up for questions. Questions were on for another 45 minutes. At this point Feynman was literally dying of stomach cancer. I remember one question though. Some guy raises his hand and says: „Is there any physics in this reversible computer business?“. Feymann stood on his tiptoes, looked over the lecturer at this guy and said:  „What do you mean physics? Physics is the study of nature. This is engineering. It's all engineering!“. I don't think it's quite correct. It was a very applied problem.

Going back to your own research. Why did you set your main focus in low temperatures substances?

I went to Cornell University for graduate study after being graduated at Caltech. First semester there were two courses. One was physics colloquium and one was a solid state seminar on new refrigeration devices Helium-3, Helium-4, dilution refrigerator which will give you continuous cooling down to extremely low temperatures. That's pretty cold. Other process has been suggested by Russian theorist Isaak Pomeranchuk, a member of the Landau school. So very broad interest. He predicted that if you compress liquid Helium-3 at these very low temperatures until you started forming solid. As you form the solid, the liquid would cool again. You could essentially reach absolute zero, but it really does not happend in fact.

This would give me the opportunity of looking at nature in a new and different way. The first year of graduate study I built Helium-3 and Helium-4 dilusion refrigerator. Some other people were involved in that too. Then the second and third year I built this Pomeranchuk cell. I think it was the best Pomeranchuk cell that has ever been built. Then I incorporated and it worked well so I can actually use nuclear magnetic resonance. Anyway, that's how it all happened.

Most people do not know much about superfluidity of Helium 3. Is it possible to explain your discovery and your lifelong work in a few sentences?

I'll try. Helium-4 is superfluid but Helium-4 atoms are Bose particles. And Bose particles are the friendly particles of nature. They all like to be in the same quantum state. Imagine Helium-4 atoms scattering off the wall. So what's status are they scattering to? There are so many atoms in this condense state already. The probability of scattering in any state is proportial to number of atoms in that momentum state. The probability is enormously high that it will scatter back. So you end up having this macroscopically occupied state. Helium-4 has zero friction. That makes it superfluent. So that's kind of introduction what superfluid is.

Helium-3 is very different though. Helium-3 atoms are firm particles or so called anti-social particles of nature. They only two can occupy the same momentum state. One with the spin up and one with spin down because there're are only two states available. There're firm particles and no two can be in the same quantum state. Why would that state then behave like a superfluid? The answer to that has to do with then superconductivity in the BCS theory (proposed by Bardeen, Cooper and Schrieffer).

John Bardeen was one of very few people that has won two Nobel prizes in the same field. He is very quiet guy but with very powerful ideas. I got my degree in spring of 1972 and that summer was an International temperature conference in Boulder, Colorado. These conferences always have big banquets. I ended up sitting right across the table from John Bardeen. John is very quiet but when he was young he stuttered. I had just discovered the new BCS state during the banquet. I was really interested in his opinion and eventually I screwed up my courage and I asked him what he thought about this Helium-3 business.  In order not to stutter he simply spoke very slowly and said: „Very interesting.“

You probably don't want to put this in your article...We were eating this elegant dinner on paper plates. The blast thing was that there was exactly one toilet for men and one for women. There were probably one thousand people in this huge hall. After dinner, women were lined up, probably hundred, to use this one toilet. No one was using men's toilet. We were just going over the hills and I would like to say that I shared the tree with John Bardeen.

You recently visited Slovak nuclear power plant in Mochovce. What were your impressions?

It was fascinating. Of course, for me it was just another toy to look at and it wasn't my toy. I knew a lot about nuclear power plants but I've never seen one before.

What do you think about nuclear energy?

There have been three serious accidents in the history of nuclear energy. Chernobyl was of course the worst. I don't think that accident is likely to happen ever again. There was a lot of incompetence I think in that accident. The Fukushima accident, the most recent one, it was mistake in the strategy that the pumps that cooled the reactor they were low enough. So this huge tsunami flooded the pumps and there was nothing that circulated the water. They had sort of meltdown so the moderator rods couldn't be moved.

That was a really serious accident. I thinks it's the one that will never be made again. It's something that's relatively easy to correct. We've been generating power using nuclear reactors for about 20 years. Do you know how many nuclear reactors are currently in operation?

I'm not exactly sure but it must be over 400 in operation...

So if you multiply 20 years by number of nuclear recators in operation, that's 8.000 years with the experience using nuclear reactors. I think there're relatively safe but when something happens like Fukushima as an example, the consequences are enormous. I think the consequences aren't just release of radiaton. You have to take into consideration the political aspect. If we have another Fukushima, the probability that anyone worldwide would be able to build another nuclear reactor goes way down. So I hope that the people who are designing these things are driven by that fear rather than by cost.

Do you think it's possible to build 100 % safe nuclear reactor these days?

Asteroid comes in and gets nuclear reactor. You cannot guard against that and there are other things. The question is Can nuclear reactors be made safer? I think the answer is probably "yes". It's very complicated because that increases the cost. Then you can ask, if you increase the cost of nuclear reactors to the point when no more are made, then in fact we will supoort the energy production by burning coal. That has all sorts of political and also ecological ramifications.

So you're damned if you use nucleus and you're damned if you don't. You can't reach completely safety. Human activity will almost invariably have an impact on the planet.

The attitude of people in Europe towards nuclear energy is very different. General view is that people in Western Europe are against and citizens in Central and Eastern Europe are more familiar with the use of this technology. What is the situation in USA like?

We're building so few nuclear plants now. I would probably have to call Steve Chu to ask him becuase I'm sure he knows. It's sort of interesting, Steven Chu and I were at Bell Laboratories together and very independently we both decided to go to Stanford University. He called me up and said: „'Osheroff I'm going to Stanford University and you have to come with me“. So we were both in the Physics department.

It's been very difficult in United States to build nuclear reactors. Every time when there's an accident it makes it harder and it's not just in the USA but everywhere. No one wants to have one of those things fail in their backyard or in their country.

Worldwide consumption of electricity will most certainly increase in the upcoming decades. According to you, what forms of energy will dominate in the future?

Certainly one that people are looking and I've actually seen some activities is solar energy. Using silicon solar cells. You get these solar farms as they are called but there are other ways of doing it. I guess silicon solar cells are technology that's well understood right now. Of course you can focus the sunlight on something different. It's a thermal process. The best solar cell are about 20 % efficient I think. You have to look how efficient the thermal devices are. So these numbers are pretty well known. I think that people that build it are looking at lots of issues besides what fraction of the sunlight we can convert to electricity. That's not exactly the problem of the question that they're asking.

I think we have to stop burning fossil fuels. Certainly petrol I think we're gonna run out. Coal, before we run out it will sufficiently poison the atmosphere. It would be a blessing if we would stop.

I don't know what the future of energy is. My personal feeling is that the more nuclear reactors we have, the more chance that the design will be safe and right. But the more nuclear reactors we have, the chances that the mistake is made and you have released the large amounts of radiation goes higher too. I think that the next generation of nuclear reactors will probably be more expensive and hopefully safer.

Notice: The interview was prepared in cooperation with energia.sk's Mr. Michal Jesenič.

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