Interview with Michael M. Shara

Part of the Einstein exhibition.

What challenges do we face in presenting Einstein to the public?

The exhibition itself is really in two major parts. There certainly is Einstein's physics. We want to explain General Relativity, Special Relativity?the core of the great contributions that he made to physics?though he also made extraordinary other contributions via Brownian motion, the photoelectric effect, for which he won the Nobel Prize, not for Relativity. Relativity was considered too suspect or too avant-garde at the time that he was awarded the Nobel Prize. So we need to explain his physics to the public insofar as possible. Of course, that's a challenge, it's non-trivial.

The other part of the exhibition is Einstein the man. There is this funny notion of him as an iconic, long-white-haired genius whose theories were incomprehensible to the public, who was a lousy student as a kid, who is the father of the atomic bomb, and who lived in an ivory tower all of his life. And that's at least as untrue as many of the misconceptions about his physics.

In particular, he was highly engaged in the politics and social issues of the day, and he had profound influences certainly in the development of the atomic bomb but he was by no means the father of the atomic bomb. He had nothing to do with the practical development of it. He was strongly anti-war, he was strongly anti-fascist, he was anti-McCarthy. That is, he defended people at a time when it was very unpopular to defend them. He had many ties with many famous people around the world and he used his influence where he could for things that were really very good. So he was highly engaged. Also he was a strong supporter of the nascent state of Israel and of The Hebrew University of Jerusalem. There are many facets of his life that I think are hardly known by the public and it's our challenge to make people aware of all of this, as well as his very complex family life. He had two wives, mistresses, had complex relationships with his children, and we have documentation to show all of that also.

So we have a very rich part of the exhibition that's going to be his personal life, his political life, his influence on the society of the day, as well as the challenge of getting across these very abstract and yet very concrete and practical problems in physics that he tackled.

What's the easiest way for someone who's not a scientist to understand Relativity? Isn't there a quote about courting a young girl and sitting on a hot cinder by which Einstein explained relativity?

He said that very tongue-in-cheek. That quote, as near as I can remember it, is: "When you have a pretty girl sitting on your lap, an hour seems like a second; when you're sitting on a hot stove, a second seems like an hour." And the fact that he used both heat and a pretty girl tells you something about Einstein. There's a little bit of Freud in all of that. It's very much the essence of the man.

And there's a lot to it. What he was trying to get across was that time is relative in different frames of reference. That is, if you and I are sitting together in a room, we're moving through space and time together at the same speed and our watches tick at the same rate. If you and I synchronize our watches, and then we sit here and have a conversation for an hour, even if we have atomic clocks on our wrists, which can measure a trillionth of a trillionth of a second, our time will be the same at the end.

But let's say you and I synchronize our watches, and then you go off and hop in a taxi and whiz around Manhattan. Or better still, if you get in a space ship and go whizzing off to the ends of the solar system at nearly the speed of light and come back, our watches will not be synchronized anymore. Time is not a universal thing. That is, time does not tick by at the same rate for observers who are moving relative to each other. That's a shocking thing. Because even today, we all know, we've been taught since childhood that there is universal time. Right? There's time in Greenwich, England, everything is U.T., universal time, as it's called. It ain't so!

Special Relativity teaches us that time flows at different rates for different observers, people who are moving relative to each other in different frames of reference. Again, by frames of reference, I mean two people who are moving at the same speed relative to the universe.

And then in General Relativity, which is a generalization of that theory, what Einstein finds is that, and I'm going to encapsulate it in the same way that he encapsulated Special Relativity in that quote about the hot stove and the pretty girl?it's not quite as funny but it's even more profound?and that is the following: matter tells space-time how to curve, and curved space-time tells matter how to move. And that statement, that pair of statements, explains how gravity works.

The reason that the Earth goes around the Sun is that the Sun bends the space-time around itself, just like a heavy weight placed in the middle of a trampoline warps the surface of the trampoline. A marble rolled across a flat trampoline with no heavy weight follows a straight line, but a marble rolled across the surface of a trampoline with a heavy weight in it follows a curved path. And if you roll that marble just right it will follow an orbit around that heavy weight. That's why the Earth goes around the Sun. That's the essence of General Relativity. That's what Einstein explained to us.

We're going to have all sorts of videos and movies and text and even some hands-on experiments to show you how matter warps space and how warped space causes matter to move.

After visiting the Einstein exhibition, can visitors expand on what they've learned by coming to the Rose Center?

The most direct connections between the Einstein exhibition and the Rose Center are, first of all, in our Black Hole Theater, where you see the warping of space-time. There are some beautiful videos of that which we're going to expand on in the Einstein show, so there's a direct one-to-one connection there. The next connection is in the Big Bang Theater, the lower half of the sphere. It recreates the creation of the universe, emphasizing that the expansion of space and time gave rise to the birth of all the matter and the energy in the universe. We see galaxies forming and swirling around each other, dancing around each other, and colliding with each other, to form new galaxies. And this kind of physics, this kind of strongly interactive physics, is all based upon General Relativity's equations of motion, of bending and warping space-time, and how matter follows that space-time bend.

Is it fair to say that our understanding of those things is built on a foundation of Einstein's work?

Absolutely. We would not understand the expansion of the universe, the creation of the universe, or how matter behaves on the large scale in the universe were it not for General Relativity. And had Einstein not come along and explained this at the turn of the century, we might still not understand it. Someone would have explained Special Relativity. That would have happened within ten, fifteen, twenty years. There were so many clues there, it was such a ripe plum to be picked, that some physicist would have come along to pick it. There were all sorts of hints both experimental and theoretical that were there. I don't know who would have done it, but there was someone else waiting to take advantage of all of that. General Relativity? We might still not have it today.

Would you talk a little bit about how Einstein's physics relate to your own research?

I do several fields of research that are closely coupled in with both Special and General Relativity. I do nova explosions, which are thermonuclear runaways on the surfaces of compact white dwarf stars and also on neutron stars. To understand the physics of these objects you really need to understand the physics of what is called degenerate matter, matter that is compacted down to ultra-high densities, and the nuclear explosions on their surfaces. Special Relativity is essential to this effort. You also need to understand General Relativity because near a neutron star, you warp and you bend space-time very very strongly. We'd have no clue how any of these explosions happened and how that warping occurred, if it weren't for Einsteinian physics.

I also do surveys, with my postdocs, of the very nearest stars and, in particular, some of those very nearby stars pass in front of other stars and they curve light, they actually bend the light from the distance stars, acting like gravitational lenses, something that was first predicted by Einstein in his General Theory of Relativity. So my own research is deeply impacted by General Relativity and by Einstein's work.

Can you share your thoughts about this "theory of everything," which seems like a Holy Grail?

It certainly is. It's something that Einstein himself pursued vigorously from, oh, around 1920 onwards. Einstein believed in his heart that there must be a simple, beautiful—and beautiful is a technical term, in some sense, in physics—a beautiful theory that explains everything, that would explain all the laws of physics. That is, you could unite General Relativity, Special Relativity, electromagnetism, solid state physics, thermodynamics, the strong nuclear force, the weak nuclear force?everything into one simple theory with a simple set of equations that you could write down, from which all the complexity of the universe can be derived. And he failed. He spent the last thirty or thirty-five years of his life in pursuit of this Holy Grail, and he absolutely did not succeed.

Since his death, the theories of the strong nuclear force, the weak nuclear force, and electromagnetism have been unified into a single theory, and it's called the Standard Theory of elementary particle physics and also of electromagnetism. And that's a tremendous accomplishment, which has won several Nobel Prizes for the people who did it. The grandfather of this, or I should say the godfather of all of this, is Einstein. It was Einstein's vision that there must be a unified theory that lead to the creation of this partially unified theory.

But nobody has yet succeeded in unifying these theories with gravity. And the reason is that gravity itself is a classical theory. By that we mean it's a non-quantum theory. It doesn't address or it doesn't unify gravity with what goes on at the very smallest level. And Einstein himself was terribly troubled by quantum theory. The idea of statistical uncertainty, or in his words that "God does not play dice with the universe," was something that really gave him a very hard time. That's probably the reason in the end that he didn't succeed, because he refused to accept quantum theory, which has a very very powerful basis in reality, and try to unify it, somehow, with his theory of gravity.

Now there must be a super-theory, something above quantum theory and gravitational theory and electromagnetism and the strong and weak nuclear forces which will succeed in unifying them all, but nobody's there yet.

Now string theory is the best candidate today. It's not just the flavor du jour or du semaine, it's the thing that most theorists have been focusing most of their effort on for at least ten, fifteen years. And it's extraordinarily beautiful. That is, the mathematics is very beautiful and there are some interesting predictions that are made. Unfortunately there is not a single observational test that's been carried out because there isn't a single clean, simple observational prediction that is testable yet. That's the real problem with string theory.

It is possible that string theory is wrong. It may be a dead end, a dead alley that a whole generation of theoretical physicists has been going down. And a year from now, five years from now somebody may show it to be just plain wrong. And we'll need to go back to the beginning and start all over again. That's possible. This is something that Einstein himself sought for the last thirty-five years of his life and which he did not succeed in doing. But his greatest legacy, many would say, is that he turned on a whole generation of physicists to this?only a few at the beginning because most people thought it was a fool's errand, but the large majority of people who do the most difficult and most cutting-edge theoretical physic are in pursuit of this problem, that is, a unification of all of the theories in physics.

Do you believe that such a theory exists?

I certainly suspect that such a thing exists. In fact I'd be very disappointed and very unhappy if such a thing didn't exist. In some sense, the whole point of physics is unification and simplification and prediction and coming up with a beautiful theory that explains a large range of phenomena. I'm convinced that such a thing exists. I'm not convinced that it's string theory. It may well be. I hope that it is, because otherwise an enormous amount of time and effort will have been spent on nothing. Whether string theory is it or not, I don't know. But I'm absolutely convinced that there is a unified theory that will unify all the laws of physics. Whether we're a decade or a century or a millennium away from it, I don't know.

Time magazine chose Einstein as "Person of the Century." Do you agree with that assessment?

Absolutely. To my mind it was a no-brainer. I would have been very disappointed had they chosen anyone else. The fact of the matter is that, yes, he was the most influential scientist of the century, probably of all time. The only people who are up there in the same pantheon, people who have contributed similar amounts in their time periods were Newton three centuries before, Galileo, Darwin, and, perhaps half a rung down, Kepler and Mendeleyev.

But I think that there's no doubt that Einstein's influence on the 20th century, and on the 21st, has been and is going to be absolutely profound. Take a look at the Earth in 1900 and the Earth in 2000. There were more changes in that century than in the previous 2,000 years in terms of technological advances, expansion of our ability to travel and to communicate across vast distances, and practically every one of those is traceable back to Einstein, including the biological revolution. Crick and Watson could not have done what they did vis-à-vis DNA had we not known of the existence of molecules. Einstein's work on Brownian motion is fundamental to our knowledge of molecules.

The entire computer revolution can be traced to the photoelectric effect. So the entire solid state revolution, much of our economy today, and our ability to communicate information is entirely due to Einstein as well as, of course, nuclear weapons and nuclear power plants and our understanding of how the stars shine, the distances to the galaxies, the evolution of the galaxies, and the creation of the universe. We are a different race of people than we were in 1902, a century ago, utterly and completely different, because of Einstein.

How did he come to be such a celebrity? How much of it was due to his unique personality?

Once General Relativity had been demonstrated in 1919, once it was experimentally verified that the bending of starlight near the Sun occurred—it was seen during an eclipse of the Sun—once that happened, he became as well known throughout the world as Madonna is today. He was one of the pop stars of the world—he was the pop star of the world at the time. That continued up until his death and, even a half-century later, he remains this almost religious, iconic figure. Why it is that that happened is something that we're very intrigued by. How is it that it happened? The celebrity status of his life is something that we're very intrigued by. And we do try and give some focus to that, some effort to explain how that happened.

The public persona was largely humble. He certainly never put on airs. He was truly disinterested in money. It was utterly irrelevant as far as he was concerned. The search for knowledge, the search for a fundamental understanding of the universe is what drove him. That was his raison d'etre. That having been said, he spent a significant fraction of the second half of his life in the public eye doing very public things. And he was willing to use his celebrity status to advance causes that he felt were important. So he wasn't withdrawn. He was a humble man, but not a withdrawn man. He was willing to be a public personality when it was useful and necessary to do so. So he was willing to use his status.

Now he was an eccentric, a true eccentric, though not more eccentric, frankly, than many of the scientists I know. Many of my colleagues are eccentric in the same sort of way, in physics and in chemistry, in mathematics and biology. What I mean is that, when you get gripped or almost obsessed by a problem in science, when a problem in science becomes the thing that occupies most of your waking hours, you become "Einsteinian." You don't become as bright as Einstein, OK, you don't become necessarily as focused as he was, but you begin to behave in slightly Einsteinian ways.

The public was aware of this behavior because of Einstein, because he was so famous, but I have to tell you that there are a million quasi-Einsteins or somewhat-Einsteins running around on the streets of the United States. For some of them, occasionally myself too, you need a butterfly net, because when you begin to think of the science problem, when you focus on a science problem, especially when you're conceiving how to do an experiment or an observation or when you're writing the paper, you tend to shut out absolutely everything around you almost to the point of not eating, hopefully not to the point of not bathing, but you can really focus utterly on what it is that you're doing. Einstein was the extreme, and the public saw that and thought of him as this highly eccentric genius. They were right on both counts, but it's not too unusual in the sciences. It happens more than you think. Collectively, we are sometimes a bunch of space cadets.

Einstein was an extraordinary man living in extraordinary times. Was his impact as a scientist amplified by his public role?

Well, Einstein considered himself to be a citizen of the world. And he was willing to espouse causes that were very unpopular at the time. It's not an accident that the FBI had a 1,400-page file on him, which is now available on-line by the way. He found McCarthyism utterly repulsive and he defended people who were being attacked by McCarthy and by the House Committee on Un-American Activities, and so on. He hated nuclear weapons. He espoused a world government. He felt that that was the only way to avoid destruction of the human race. These were all things, all causes that he espoused. He truly considered himself a citizen of the world.

Now he certainly did take American citizenship, and he considered himself a loyal American. As a loyal American he felt it was his obligation to speak out against fascism, against nuclear arms, against militarism of all sorts. He abhorred it in Germany. One of the reasons he moved to Switzerland—he spent his teenage years and 20s in Switzerland—was that he was nauseated by the First World War and by German militarism. He was one of just two or three professors in Germany who were willing to sign a manifesto against Germans fighting in the First World War. So that's the kind of person that he was.

He was someone who had this vision of a united mankind, probably very utopian, probably very unrealistic, but at the same time he was firmly enough grounded in reality that on August 2, 1939, just 29 days before the invasion of Poland by Hitler, he sent to the White House, to Franklin Roosevelt, a letter warning that the Nazis were likely to be developing atomic weapons and that United States had better think hard about doing the same thing. That was his one involvement in the development of the atomic bomb, his only involvement in the atomic bomb, but very seminal, very important. But he was considered by many in the White House and in government to be too much of a security risk to be involved in the actual practical development of the atomic bomb. He was not invited to come out to Los Alamos and participate in the development of the atomic bomb though he did work as a consultant for the Navy on the development of high explosives and other kind of air defenses.

In your opinion, what's the most exciting object in the show?

We're going to have several original E=mc²'s in his own handwriting. I held some of them in my own hands, in my own gloved hands, you're not allowed to touch them of course for conservation purposes. So those to me are extraordinary. We're going to have a manuscript that he wrote, a 72-page original manuscript describing all of Special Relativity. We'll have six pages in his handwriting on exhibit at any one time; we have to rotate the pages. They have to be shown in very very low light levels. But we will have a perfect copy of all 72 pages on display all the time. We will have letters to and from his wives, children, mistresses. We will have, at least for one or two weeks at the beginning of the exhibition, the letter to Roosevelt, and Roosevelt's response, which has never been shown before in the United States. And we'll have the offer of the Presidency of the State of Israel from David Ben-Gurion as well as Einstein's letter graciously but regretfully declining that offer.

The collection of objects is going to be truly extraordinary. Nothing like this has ever been on exhibit anywhere before, anywhere in the world. And except for the few other venues where this exhibition will be, I don't think it ever will happen again. This is going to be a really outstanding exhibition.

What two or three ideas do you hope people will take away from the show?

That Einstein was an extraordinary human being as well as the most extraordinary scientist of all time. That he changed the world forever in very very positive ways. And that we can all learn a lot by emulating both his character for non-scientists and, frankly, his scientific ethic, his hard work, his diligence, his view of the whole picture, and his quest for truth as a scientist.