Albert Einstein
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BBC Sounds. Music, radio, podcasts. This is In Our Time from BBC Radio 4 and this is one of almost a thousand episodes you can find on BBC Sounds and on our website. If you scroll down the page for this edition, you'll find a reading list to go with it. I hope you enjoy the programme. Hello, in 1905, Albert Einstein, then a technical expert at a Swiss patent office, published four papers that would have changed the world of physics.

That became known as his Annus Mirabilis, his year of miracles or wonders. And it is a minor miracle that a young man whose academic record had been so underwhelming became so central. But some championed his theory of special relativity, the principle of mass-energy equivalence that followed, and his explanation of Brownian motion and the photoelectric effect. And when a solar eclipse proved his theory that gravity would bend light, he became an international celebrity.

With me to discuss young Einstein are Richard Staley, Professor in History and Philosophy of Science at the University of Cambridge and Professor in History of Science at the University of Copenhagen, Diana Cormis-Buchwald, Robert M. Abbey Professor of History and Director and General Editor of the Einstein Papers Project at the California Institute of Technology, and John Heilbron, Professor Emeritus at the University of California, Berkeley.

John, can you tell us about Einstein's early childhood and the family business? I can try. The thing perhaps to keep in mind about Einstein, just to get the chronology right, would be that he was 21 years old in the year 1900, a fresh graduate from the Polytechnic Institute in Zurich, jobless, stateless, and stubborn.

He was born in Ulm in Bavaria. His family, his father and his uncle, were proprietors of an electrical technology business, making meters and lighting up cities and so on. And so he grew up in a family where electrodynamics was a sibling, which made it quite convenient for his later work since relativity does indeed emerge from the environment of electrodynamical theory.

He was educated at first at home. At an early age, the family moved to Munich, where the prospects for the electrotechnical business were better. And he went to a primary school, which was a Catholic school. He was the only Jew in the class. And he learned whatever was taught to children about Christianity.

which the family tried to correct, although it was not observant. And also when he went to the gymnasium at the age of nine, he had to take two hours of religious instruction every week in the religion of his forefathers. So he learned Judaism then. And he became very fervent until he was 12 and preparing for bar mitzvah, at which point he

He dropped it, retaining, however, a religiosity. Were there any signs, if taken as to his early teen years, any signs of what were to be future brilliance? Well, in the subjects in which he was interested. He did very well in the gymnasium, physics and mathematics. But he didn't do well in subjects he didn't care for, like French and chemistry.

And that was to haunt him because the family electrotechnology business did not flourish in Munich. So the family moved to northern Italy where the business had been invited to electrify some villages. And they left Albert behind in a gymnasium in Munich. He didn't like this abandonment.

and eventually got leave to join his family in northern Italy, which meant he did not receive the obitur, the leaving certificate from the gymnasium,

which meant he didn't have leave to enter any German university. And when he took the entrance examinations for the technical school in Zurich, he flunked French and chemistry. So it did have an influence on his later life. So in terms of the formal education at an elite level that he was offered at the time, he didn't do very well.

Except in the subjects that he wanted to do well. Except in the subjects that he wanted to do well. He was a stubborn man. But eventually...

He went to a finishing school, a good secondary Swiss school, and there he had to become proficient in chemistry. And he squeaked by, just squeaked by in French. Graduates of the school had the right to enter the Polytechnic Institute without further exams. So in 1897, we have Einstein emerging on the threshold of life, about to enter the Polytechnic Institute in Zurich. Thank you very much.

Dana Buchwald, how much was his education helping him to develop skills that were later so celebrated? He was only 17 years old when he was accepted to the Polytechnic Institute. He studied from 1896 to 1900. And when he took his exams from the local school at age 17...

In his mediocre French test, Mes projets d'avenir, My Projects for the Future, he wrote that he wanted his vocation to be physics, especially theoretical physics.

So at the age of 17, Einstein had already decided his path through university, and it was a path that was contrary to the one that his father and uncle would have preferred. They would have liked him to study engineering, whereas he registered into Section 6A of the Polytechnic, which was the one for theoretical physics and mathematics that would produce high school teachers.

The school was a renowned school. There were only very few students admitted to the theoretical section. And apart from the lectures of the reigning professor Heinrich Weber, his study of theory in physics consisted primarily of self-instruction. We have his lecture notes and they indicate his enthusiasm for this subject. But what's important to note

is that he did not study the most important topics of the day. He did not study Maxwell's equations and theory of electromagnetism. That was not taught. He enjoyed, however, laboratory work. And what's interesting to note is that the only top grade that he received at university was for laboratory work. Can we move to his experience at the patient office?

and tell people what the patent office was at the time and how he developed his reach and his ideas, please. He was an examiner of technical submissions to the intellectual property office. Patents were submitted, and what he had to do was to examine the feasibility of the patent. And these were, in many cases, mechanical and electrical devices.

He had a great library at his disposal. He had scientific journals at his disposal. And we know that he read broadly and widely in the most interesting literature at the time. It's hard to imagine that Einstein spent seven years at the patent office. He had a difficult time personally then, too. He had to support a family. He had a young boy.

But what's so interesting is that in the seven years by his own account, before he published his papers of 1905, he was extremely active. He published many reviews of articles and books, and we have evidence that he studied the most recent literature on the theory of electron that was just discovered, on electromagnetism, on thermoelectricity, physical chemistry.

It was a good environment for him because it guaranteed him a steady income, which he would otherwise not have had.

given that his father had gone bankrupt. Thank you. Richard Staley, what were the issues in theoretical physics in the late 19th century that were looking to be resolved and those he took on? We can get a good sense of that from two luminaries who spoke at the 1900 International Congress of Physics, Lord Kelvin up from Britain and Henri Poincaré from France.

Lord Kelvin developed one of two clouds on the horizon of dynamical theory that he'd identified earlier. These were, on the first hand, the failure of experiments to detect the motion of the Earth through the ether, a problem in electrodynamic theory, and on the second hand, the insufficiency of the equipetition of energy.

The first one was a major issue for lots of people in the period. Diana mentioned the importance of Maxwell's equations as a key element. Electromagnetic theory had swept physics and offered quite a new set of ideals and guiding insights. It was a field theory, action propagated over time across space. And the embrace of electromagnetic fields had to occur through an ether,

And it was recognized that the Earth's motion through the ether just wasn't being picked up in experiments. A very sophisticated experiment from Albert Mickelson had been carried out and there was a null result. Now, Kelvin's answer to this was actually we're doing OK with this problem. Lorentz and others had introduced the concept of the electron, a charged particle.

And a charged particle moving through an electromagnetic field, it was natural that it should be affected by that motion. And Lorentz had suggested that charged particles, in fact all particles, might contract in their direction of motion so as to compensate the expected effect of motion through the aether.

So Kelvin was quite sanguine about the prospects of dealing with this question. The second question that he spoke on was a question about the equipetition of energy. That was looking at statistical mechanics and the ways that gas molecules interacted with each other. And he thought that it was hardly believable that the average kinetic energy of every degree of freedom in a gas could be the same as Maxwell and Boltzmann had proposed. And

And in this case, Kelvin simply thought one should get rid of this, forget that. Interestingly, as Diana said, Albert Einstein was focused, in fact, quite strongly on ether theory. And the other thing that he took up really strongly in much of his private study was a study of statistical mechanics. So these are two problems from Kelvin. The other person I'd like to mention is Henri Poincaré, the mathematician, who gave a much more general perspective on

and he talked about the need to go beyond a search for particular mechanisms to look for unity in all the different areas of physics and he was proposing a search for general principles and particularly interested in the relationships between general principles like the principle of relativity and the principle of action and reaction and Einstein also took that really seriously He was very fond of thought experiments Einstein, how did that work for him?

Yeah, he was extremely fond of thought experiments. He was very good at approaching the questions of the assumptions underlying a piece of work and tweaking them this way and that to see how they could be brought out and so on. But there are also two particular thought experiments that provided guides to two of his major theoretical breakthroughs.

The first is one that he thought of while he was 15, and we can give a history to it. This was the idea, what happens when you catch up with a light wave?

People looking at the reading that he'd been doing as a child have talked about the way that children's books on science had pictured the possibility of travelling at the speed of light through a telegraph wire and imagined what one would experience there. Well, Einstein, if he in fact drew on that, transposes it to take the question into light.

His view on that must have changed over time. In one way, in the Maximilian theory, what you would see is a frozen light wave stretching before you. But he was suspicious of the frame of reference of the ether and the way that that was not supposed to move, that was absolute. So he explored an emission theory of light and was puzzling over this thought experiment for a good 10 years before, in a way, he resolved those questions in the special theory of relativity theory.

The second thought experiment came while he was in the patent office in 1907. And he describes much later the extraordinary day when he suddenly realized that a man falling won't feel his own weight. And that was for him a key to link the theory of gravitation...

with the question of acceleration and to recognize that gravitation and acceleration were equivalent and the inertial mass that resists motion would be the same as the gravitational mass that is subject to gravitation. And then to use that insight and link...

speculative techniques to drill mathematically with acceleration to the question of gravitation. And that he developed into the seed of the general theory of relativity, which took another eight years or so to develop. Thank you, John. Let's look at 1905, Einstein when he was in his mid-twenties. This is known as the Annus Mirabilis, the year of wonders. What were the wonders?

Well, you've already mentioned them, I think, at the outset of our discussions. There was electrodynamics, there was the nature of light, there was the size of molecules.

And the whole series ends with a big bang of E equals MC squared. So, indeed, a wondrous year for Einstein. Have we any idea how this cluster of extraordinary ideas came at the same time from this man? Well, I think there are a deposit of solutions that he had worked out to the major problem of

late 19th century physics, which is, or was, the connection between ether and matter. Both were problematic at the time. Richards has mentioned the equipartition of energy, but to be even simpler about the story, the question was whether atoms existed, or whether matter was continuous, or whether it mattered whether you said matter was continuous or discrete or

Thermodynamics was a very nice subject and got by without any assumptions about the internal composition of matter. So, ponderable bodies were a problem. As for the ether, this hypothetical stationary substance that carried light waves and electromagnetic interactions, this had the distinct difficulty that it was hard to get in touch with it.

Bodies moving through it should experience something, but even the most refined experiments revealed nothing. So one way out of this would just say, we'll drop the ether and everything will be better.

However, the aether did some things and one of the things it did which, well two things of great importance. First it did serve as an absolute reference frame with respect to which you could tell whether or not you were in motion. The second thing it did was to provide a velocity for light. It's the characteristics of the aether that determine how fast the light should propagate. And if you get rid of the aether, you get rid of that possibility.

So in the relativity theory, which was the portion of this marvelous work that dealt with the electrodynamics of moving bodies, you have the problem of giving every person his own or her own ether. Because the speed of light is the same with respect to the observer, no matter what the observer is doing. However fast or slow is moving with respect to other people, you cannot...

Change the velocity of the light with respect to yourself. Always talking about dealing in vacuum. Okay, so we get back to this question. What does light look like when you catch up to it? You can't catch up to it. You can run after it with the speed of light, and it will still recede from you at the speed of light.

If you cleave to that, which is one of the principles of the special theory of relativity, and you also cleave to the proposition that there's no experiment that you can do in reference frames that move at uniform velocity with respect to one another, no possible experiment that you can do which will tell you which one of them actually is in motion. That's the principle of relativity long held to be

applicable to the motions of ordinary bodies, but not held to be applicable to electromagnetic effects. Now Einstein says, aha, it also affects electromagnetism. So I'm going to hold fast to the principle of relativity. I'm going to hold fast to this bizarre notion about light and see what the consequences are. And the consequences are mind-boggling.

These are, among other things, that observers in relative motion to one another. The yardstick carried by the moving one will be less than a yard as measured by you in your stationary frame and larger.

That fellow passing you with some uniform velocity, you'll think his clocks are going slow. You will find events are simultaneous, which he thinks are not simultaneous, and so on and so on. And these are bewildering, mind-boggling consequences of these two presuppositions.

each of which separately is understandable. Diana, how did he react to his own theories, inventions? Was he delighted with them? Einstein was always very happy to work.

He was a very hard worker his whole life, and he did it with great pleasure. And he sought solitude at times, and at other times he was perfectly delighted to work in the middle of chaos, in the middle of a very busy household, or in the middle of a lecture hall.

Now, he understood, as John and Richard said, that there is the need for a unified theory or a unified theoretical formulation of all these problems, which we think are absolutely distinct in our sense impressions. One is light. One is pressure. One is weight.

One is force, and nevertheless, for him, the need was there to delight in the unity of all these processes and all these phenomena, and to a certain extent, to delight in the unity of the theories. We have letters to his students, to family, to friends,

in which he says things for which he later became famous. Don't let education spoil your pleasure in doing science. Do what you find interesting. Don't waste away.

Don't be intimidated by school and by figures in authority. All of what you're learning is bound to be forgotten, he would say, but the delight in science is among the most precious things that you have. They delight you and they last forever.

for a long time, for the rest of your life. Richard, Richard Stirling, can you tell us about the distinction between a theoretical approach to physics at that time and an experimental one? I think this picks up on an interesting point that Diana made about Einstein, which is that actually in his, before he went into his study, he thought he'd become a theoretical physicist.

But in his work, he really delighted in the laboratory. And he always kept a pole between theoretical insight and experimental work. And in his own set of groundbreaking papers, it wasn't just the ideas that guided him. He often looked for a sphere in which they would become relevant experimentally.

So personally, he moves always between theory and experiment, although over time, and especially with the gravitational work he did, which relied upon extensive mathematical work, over time he came to think that the mathematical harmony and beauty of the equations provided a really important and strong insight into the way in which one should develop theory. But amongst his community, interestingly...

People recognized his theoretical gifts, and one of his major patrons early on was Max Planck, who was one of the first people who described himself and thought of himself as a theoretical physicist. And for Max Planck, Einstein was a brilliant example of the new kind of physicist.

Yes, they were friends, oddly enough, though not quite of the same generation. And Planck was Herger Heimrott Planck, a conservative man. And we know about Einstein, for whom conservatism was the last desirable quality.

They admired one another as, and this was the term they used, artists in the exercise of their profession. And they were friends up until the time that Einstein left Europe under the anticipation of the Nazis.

So Planck was very important in the advancement of Einstein's career. He was the editor of the Annalen der Physik, the leading German and maybe the world's leading journal in physics at the time. It was Planck who, as editor for theoretical papers, published everything that Einstein sent him, as far as I know.

And he, Planck, was so taken with the theory of relativity that he began to develop in the directions that Einstein had not considered, or at least hadn't published. So into thermodynamics, into mechanics, and so on. And then he brought Einstein to Berlin in order, as Einstein put it, to lay golden eggs.

Planck offered him a sinecure heading a non-existent institute for theoretical physics and the leisure to do what he wanted. This was in 1912, just before 1913, just before the outbreak of the war. And Einstein did indeed lay golden eggs. And during this time, he developed his general relativity. At Amica Insurance.

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Was Einstein famous by then, or were his detractors in the ascendance? Einstein was in the ascendance at that time. He wasn't, by any stretch of imagination, famous at all.

He had become very well known between 1907 and 1911. So he was still at the patent office when he's visited by a very distinguished physicist called Max von Laue, who meets with him for about two hours and then says after two hours, this fellow is revolutionary.

He has overturned all of mechanics, electrodynamics, and this on the basis of statistics. So by 1909 he is known to at least

the top circle of theoretical physicists. But as John Heilbron did in his work many, many years ago, we have to remember that there were very, very, very few theoretical physicists in the world in 1909. So he's invited to the Solvay Conference, and this was an interesting conference because it was the first conference that we know of dedicated to a particular topic in physics.

and the topic in physics was the crisis created by Max Planck in 1900 and by Einstein in 1905 and 1906. What is the quantum and how do we deal with it? Einstein accepted very graciously to attend the Select Workshop, really. It was a workshop. The papers were pre-circulated. There were very few people there.

but they were the creme de la creme in particular of French science, German science, both experimentalists and theoretical physicists. It's hard to say what it meant for Einstein himself. He called it the witch's Sabbath. He called it a delight for the diabolical Jesuits. He called it a lamentation over the ruins of Jerusalem. He said he had learned nothing new from

But what we do know is that he himself made a great impression on these scientists who are mostly men, but Marie Curie was also there.

They came away from this conference realising that Einstein was formulating a research agenda for the next 10, 20 years, and this is entirely what happened. Thank you. Richard, Richard, what, if anything, changed for Einstein, or became clearer, with the outbreak of World War I? Before World War I, he'd moved to Berlin, and he experienced...

therefore in the midst of the Prussian control. And one of the things that he experienced was that everyone around him was swept up by the fever for war.

One example of this was a manifesto to the cultured world that was signed by 93 German professors and men of science and the humanities who argued that one should stand behind German militarism, that it was all infamous lies that Germany had gone into Belgium without a just right and so on.

And Einstein recognized this for the chauvinism that it was. And with two or three others, he signed and helped draft, in fact, a manifesto to the Europeans that expressed an internationalist pacifist approach that talked about the connections between the different groups of Europe and argued for this above chauvinism.

And he also started going to pacifist meetings that were held in Berlin for a while and then were shut down by the authorities.

So one thing is that he began to recognize himself as a political figure. And that also carried on in relation to his group. John talked about his family making sure that he was educated as a Jew. But actually, he himself later said that he only realized that he was a Jew when he went to Berlin.

and lived in an environment where there were major Jewish groups and quite a bit of anti-Semitism. In a way, after the war, he took the platform that was provided and became a public intellectual. John, John Hillman, one thing that emerged during the war was his general theory of relativity. Can you tell us about that?

Yes, this was the principal golden egg laid during the time. I should say, just to follow up a bit on what Richard has said, Planck was one of the signatories of the Manifesto of the Ninety-Three Intellectuals, and the only one who repudiated his signature during the war, which was another bond between the two men.

Well, as to the golden egg, as in the case of relativity, special relativity, the beginnings are comprehensible and are not so easy to express or explain.

The beginnings in this case are known to every student of A-level physics. It is just Galileo's proposition that if there were no atmosphere, bodies fell in a vacuum to the Earth, they'd all fall with the same acceleration. This we all know. This was considered a contingent fact. It's just the way things are up until Einstein. And Einstein thought there was some veiled deep truth in this fact.

And he developed it into an equivalence between ordinary sorts of accelerations, as when you're pushed, and gravitational acceleration. He gave, as his famous example, a person sitting at rest in the Earth's gravitational field and an astronaut being shot up by his rocket in the opposite direction.

Both of them, they're blindfolded, incidentally, so they have no visual clues as to what's going on. Both of them feel a force on their bottoms. The man rests in the gravitational field of the Earth because the Earth is pulling down on him and the chair is pushing up on him. And the astronaut, he feels the acceleration from the rockets that are transmitted to him through his seat.

Okay. That means that what you know about the indistinguishability, the equivalence, suggests that what you know about inertial motion, the standard push-pulls, will also be true of somebody sitting in a stationary gravitational field. Special relativity has told you, among other things, that the moving body exhibits to you stationary clocks that are moving slower than your clock.

Okay. In the gravitational field, the analogy will be the clocks run slower as they are dropped deeper and deeper into gravity. Now, that is a fantastic finding. Also, you can reason in the same qualitative way and get the bending of light as it goes past large gravitating bodies. Okay.

Okay, that's straightforward enough. Anybody can understand that. But then the question arises of generalizing it, dressing it up in the mathematics that has to satisfy certain conditions of relativity and these other criteria. And pretty soon it gets very complicated and you can't get by anymore with elementary algebra. Now you've got to have mathematics so complicated that Einstein had trouble with it.

Now, these particulars, the clock and the gravitational field slowing down and the bending of light, these were on the edge of the detectable in his time. The most famous of them is, of course, the bending of light as it passes, as it grazes the sun, light from stars beyond the sun. So you will say very wisely, that's idiotic. You can't see the stars when the sun is out. You have to wait for an eclipse, a total eclipse of the sun.

take a picture of the stars at that point, and they will show a pattern. And you take a picture of the same portion of the sky when the sun is on the opposite side, and you find that the pattern is a little bit different because the light is no longer bent. Such an eclipse occurred in 1919, and the British mounted an expedition to check on the bending, and what do you know? It is confirmed. So the confirmation is,

became a world phenomenon. Thank you. Diana, can you develop that? It suggests that he wasn't a celebrity before then. It takes four years before Einstein becomes famous. And those four years are very difficult years. But by 1920, he is indeed world famous after the eclipse expedition results that were published in November 1919.

It was a brutal war. There were revolutions. Several empires fell. Einstein comes with this new theory of the universe in which time and space are not what they were supposed to be because Newton had said that there is something called absolute space and Einstein says, no, there is no absolute space.

And we knew that the light comes from the stars in a certain way. And then the New York Times writes, "Stars are not where they seem to be." Einstein is subjected to quite serious attacks from some quite serious physicists, especially in Germany. So first he becomes rather famous in Germany for his anti-relativity attacks.

that were quite vicious and were antisemitically motivated in many cases. Then his pacifism gets attacked in 1920 as well, and he's put on a list of treasonous pacifists who should be assassinated. He personally gets quite nervous about these things.

And eventually, he decides to join a delegation of Zionists to visit the United States. And that's when his fame explodes, really, when he arrives in New York City and

There are 5,000 people in front of City Hall when he goes to visit. And he gives 17 lectures all over the United States and then comes to the UK and gives lectures in Manchester and in London. And by 1921, that spring, he is a world phenomenon. Richard, it's been mentioned that the fact that he was Jewish affected his...

reputation in the 1920s. Is it stopping him doing what he wants to do? Early on, it's not stopping him. And I want to also note that many of the people who later supported him initially had difficulties with his theory and often associated its abstract character with Jewishness. One example of that is Arnold Sommerfeld, who wrote about Einstein in those terms in 1908.

shortly before becoming convinced of Einstein's theory and becoming a major supporter of Einstein. So being anti-Semitic wasn't always decisive.

But for a group of people in the 1920s in Germany who combined anti-Semitic inclinations with conspiratorial thinking, with a faith in experiments and the good old ways of the German traditional physicist, those people became really quite dangerous for Einstein, for his reputation in the community. They were drawn together by a rabble-rouser, Paul Weiland, and...

And Einstein called out the anti-Semitism. He noted that the anti-relativity conference that had been called in Berlin actually had also featured anti-Semitic pamphlets. And he told anybody that if they wanted to debate relativity, they could do that at the annual meeting of German scientists. And there was a very important debate there where both Einstein and Lenard spoke briefly about their different positions.

But it really does show something that's really important to understand about Einstein, and that is that for most of his early life, he was extremely controversial. And he was loved while he was hated by some. And that's a very important thing in understanding why he became such an important figure over the course of the 20th century as a whole. John, you want to come in? Well, I was going to say that among those who loved him was the press, right?

And especially they liked his – he liked to play and toy with the press. And they liked to describe him as an Italian musician with his chisel head and his violin and so on. And they were quite effective in promoting his image. Yeah.

I wanted to say, add also, you know, Einstein thought or his friends thought that his life was in danger from time to time because of the anti-Semitism of the early Weimar Republic. And he was unable to attend the Nobel celebrations there.

when he won his prize, he was in Japan in order to avoid what was thought to be a threatening environment. Is there time for you to talk about his quantum mechanics and how that was received? Einstein was, as Richard said, one of the first to pick up and develop the theory that Planck had introduced in 1900 in order to account for certain things which we can forget about for the moment.

And Einstein continued to puzzle over what appeared to be discrepancies between Planck's premises and his conclusions. And Einstein was able to apply Planck's ideas outside of the range of phenomena that had led Planck to them, particularly the behavior of bodies at low temperatures. During the war, he laid a silver egg for the quantum theory, and that introduced a

essentially a hostage to fortune because it introduced probabilities into the doings of atoms, into the interior motions and so forth of atoms. In Einstein's formulation, the probabilities were provisional. But gradually, with the development of quantum physics into quantum mechanics in 1925 and 1926...

These probabilities hardened into radical probabilities. They were true of nature. Nature was probabilistic in a sense. And this Einstein could not accept. He said often...

And this probably is related to his capacity for thought experiment. He said often, theories are free creations of the human mind. That doesn't mean they're absolutely free because there is nature out there and you have to have your theories at some point if you're doing physics, agree with them, agree with the natural phenomena. But to some extent, the basis of the theories are within your control. And Einstein thought that it would be possible to impose a certain set of requirements that

And it turned out that every time he proposed a thought experiment which would convict quantum mechanics of being either inconsistent or incomplete, he was defeated by Niels Bohr.

About a decade and a half after Einstein's death, experiments did become possible. And last year, the Nobel Prize went for experiments that proved that you cannot have a physics, a quantum mechanics of the sort that Einstein wanted. Diana, how did his reputation develop in his later, very latest years among the wider public? I think it's been hinted at, but do you have anything to add?

It has always been asked, well, why has his image persisted for so long? And I've thought about it, and I think the only feasible answer to me is, number one, as John said, the love of the press. The press was very well informed when he arrived in the United States in 1921. They knew the difficulties that he was encountering.

And Einstein himself was asked in a rather controversial interview that we cannot verify word for word. But he said that his explanation for the Einstein craze is that the magic of non-comprehension attracts the reader.

A theory that is within the realm of comprehension of only a handful of people, and these were headlines actually, where famous names are mentioned and learned men and prizes of predecessors, Newton, Galileo, Kepler, etc.

It impresses us and it assumes colors of charm, of mystery. So he is a good guy in history. His deposit in the bank of physics has been remarkably steady.

even though with his work he has created a lot of alienation from science. His science is not accessible, and there have been intellectuals, let's say Lionel Trilling or Alexander Calder, who have said, you know, these scientists, they create these things that are so difficult to comprehend, and they put them at our feet.

And they're like foundlings, and we don't know what to do with them. So the incomprehensibility, I think, also plays a role in the persistence of the Einstein craze, as he called it. Well, thank you very much. Thank you very much, Dana Buchwald, John Helbron, and Richard Staley. And our studio engineer this week was Giles Aspen.

Next week, Ingmar Bergman's The Seventh Seal, set in Sweden in The Black Death, when Death himself plays chess with a returning crusader. It's a classic of world cinema and our thousandth episode. Thanks for listening. And the In Our Time podcast gets some extra time now with a few minutes of bonus material from Melvin and his guests. So can I just ask you one question? Starting with you, Diana, what was left out that grieves you that you would like to have talked about? LAUGHTER

It's very difficult to look into somebody else's mind. It's a huge challenge. And as I mentioned at some point, there is no historian of science who has written a complete biography of Albert Einstein. It is so daunting that none of us has truly attempted it. All the biographies of Einstein were written either by people who were close to him

or by journalists. Am I right, John? Yes, and you're making it worse, Diana, by publishing all this material about Einstein. Yes, the collected papers of Albert Einstein, I was thinking about it last night. I know so much about

that I am completely overwhelmed when having to summarize things. I have so many quotations in my head. I have so many events in my head. His life was immensely rich. It was not as rich maybe as Alexander von Humboldt's life, but he certainly corresponded with thousands of people and was engaged in myriad activities that we have not touched upon at all during the broadcast.

The big outlines are there, of course, as Richard said, pacifism, internationalism, but his role in the League of Nations. He joined the International Committee for Intellectual Cooperation immediately after the end of the war, and Germany was only accepted into the League of Nations in 1936. But you will remember that he left Germany.

that resigned on the theory that it would not be good to have a Swiss pacifist German Jew representing Germany just after the war on this committee. But he rejoined it. I know he rejoined it. He rejoined it. He rejoined it. And it's remarkable how many obstacles he was able to overcome.

And bringing Germany into the League of Nations was no mean feat. There was great opposition. And the fact that he travels to the Anglo-Saxon world when officially the United States in 1921 is still at war with Germany, there is not yet a peace agreement signed. And when the American Academy wants to send Einstein to the White House, President Harding refuses this.

on the grounds that he's a German, and therefore the whole academy goes with Einstein, so that it won't be seen as a particular Einstein event. So he is really swimming against the tide. Does that mean that his Swiss citizenship really didn't protect him under these circumstances? Not at all. And even when he was greeted at the harbor in New York...

At the Battery, the American newspapers were extremely finely attuned to the attacks against Einstein, both personal and relativity, and asked him those questions. And he answered immediately. He said, these are mostly anti-Semitically motivated attacks.

Everything was not rosy in the United States either. A few months later, you have the Immigration Restriction Act being instituted. Can I ask the other two if they've got any final thoughts? John, would you like to say what you would like to have talked about? I'm fascinated by Einstein's

towards quantum mechanics, as were many of his contemporaries and fellow physicists who could not understand why a man who was able to bring about such a revolution in our ideas of space and time had any little problems with the elimination of causality and so on. And there are very strong remarks made by scientists

to be sure, members of Bohr's school, but others as well, that Einstein has lost it, Einstein is not true to himself, especially since Einstein not only opposed the traditional, the widely accepted interpretation of quantum mechanics, but he was working on a theory, the general theory of relativity, which is

went out of fashion very quickly and didn't come back into fashion really until after Einstein's death. And he was also trying to meld it with theories of electrodynamics into a general field theory. It never worked. And so they thought he was not only lost his revolutionary instincts, but he lost it altogether and no longer had a sense for what was important in physics. Well, absolutely. But, um,

Generativity did not go out of fashion. It never really had. It wasn't established until much later because you could do very little with it. It wasn't useful. And the tests that confirmed generativity took half a century. And it was only in the 1950s and 60s with new generations of physicists in the United States that

that generativity started to have a glimmer of hope of being helpful in astronomy and cosmology and so on. So it didn't really go out of fashion. That I would disagree with. All right. Can I ask finally now, because we have to close sometime, Richard, what would you like to have said that you didn't say? Perhaps one of the things that's really interesting about Einstein is the combination of his intellectual daring and his moral courage. And...

That seems true both in his science and in his political life. Both of those things seem to meld, I think. And that's what I find really interesting about him. He saw more and more clearly than the other people around him. And he pointed out just where social assumptions were going awry also. And I think that was extraordinary.

Well, thank you all very much. Thank you very much. Thank you, John and Richard. I think that's a cracker. Thank you very much. I think it is fun. I haven't said anything. I was about to offer you tea or coffee. Would anybody like tea or coffee? Well, I don't know. Are you sitting around for tea? I'll have a little tea. That's very good. Let's have some tea. Tea or cheese? Yep. In Our Time with Melvyn Bragg is produced by Simon Tillotson.

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