Physicists From The United States

"The technologies which have had the most profound effects on human life are usually simple. A good example of a simple technology with profound historical consequences is hay. Nobody knows who invented hay, the idea of cutting grass in the autumn and storing it in large enough quantities to keep horses and cows alive through the winter. All we know is that the technology of hay was unknown to the Roman Empire but was known to every village of medieval Europe. Like many other crucially important technologies, hay emerged anonymously during the so-called Dark Ages. According to the Hay Theory of History, the invention of hay was the decisive event which moved the center of gravity of urban civilization from the Mediterranean basin to Northern and Western Europe. The Roman Empire did not need hay because in a Mediterranean climate the grass grows well enough in winter for animals to graze. North of the Alps, great cities dependent on horses and oxen for motive power could not exist without hay. So it was hay that allowed populations to grow and civilizations to flourish among the forests of Northern Europe. Hay moved the greatness of Rome to Paris and London, and later to Berlin and Moscow and New York."

"The expansion of life, moving out from Earth into its inheritance, is an even greater theme than the expansion of England across the Atlantic. As Hakluyt wrote that there is under our noses the great and ample country of Virginia, I am saying that there is under our noses the territory of nine planets, forty moons, ten thousand asteroids and a trillion comets."

"As we look out into the Universe and identify the many accidents of physics and astronomy that have worked together to our benefit, it almost seems as if the Universe must in some sense have known that we were coming."

"I have felt it myself. The glitter of nuclear weapons. It is irresistible if you come to them as a scientist. To feel it's there in your hands, to release this energy that fuels the stars, to let it do your bidding. To perform these miracles, to lift a million tons of rock into the sky. It is something that gives people an illusion of illimitable power, and it is, in some ways, responsible for all our troubles — this, what you might call technical arrogance, that overcomes people when they see what they can do with their minds."

"Thirty-one years ago [1948], Dick Feynman told me about his "sum over histories" version of quantum mechanics. "The electron does anything it likes," he said. "It just goes in any direction at any speed, forward or backward in time, however it likes, and then you add up the amplitudes and it gives you the wave-function." I said to him, "You're crazy." But he wasn't."

"I am acutely aware of the fact that the marriage between mathematics and physics, which was so enormously fruitful in past centuries, has recently ended in divorce."

"It has been generally believed that only the complex numbers could legitimately be used as the ground field in discussing quantum-mechanical operators. Over the complex field, Frobenius' theorem is of course not valid; the only division algebra over the complex field is formed by the complex numbers themselves. However, Frobenius' theorem is relevant precisely because the appropriate ground field for much of quantum mechanics is real rather than complex."

"The public has a distorted view of science, because children are taught in school that science is a collection of firmly established truths. In fact, science is not a collection of truths. It is a continuing exploration of mysteries. (New York Review of Books, 2011)"

"The whole point of science is that most of it is uncertain. That's why science is exciting--because we don't know. Science is all about things we don't understand. The public, of course, imagines science is just a set of facts. But it's not. Science is a process of exploring, which is always partial. We explore, and we find out things that we understand. We find out things we thought we understood were wrong. That's how it makes progress. (2014 interview)"

"After the war ended, partly disgusted by the cruel use to which his beloved physics had been put, Szilard left professional physics to explore new pastures – in his case, biology... there was a more pragmatic reason. As Szilard put it, this was an age when you took a year to discover something new in physics but only took a day to discover something new in biology."

"By the time his ideas became accepted he had already forged ahead to take up a new attitude. Szilard himself illustrated this characteristic in a story which he liked to tell about himself. He served once on a jury in a murder case. When the first vote was taken, eleven jurors were in favour of convicting, but one — Szilard — was for acquittal. Since unanimity was required, the discussion was resumed and Szilard expounded his arguments. After some time another vote was taken; the result was again eleven to one, but this time eleven were for acquittal, and one for conviction: the odd vote was Szilard’s who had in the meantime changed his mind!"

"I had not been long back from Hiroshima when I heard someone say, in Szilárd's presence; that it was the tragedy of scientists that their discoveries were used for destruction. Szilárd replied, as he more than anyone else had the right to reply; that it was not the tragedy of scientists, it is the tragedy of mankind."

"The people who have sufficient passion for the truth to give the truth a chance to prevail, if it runs counter to their bias, are in a minority. How important is this "minority?" It is difficult to say at this point, for, at the present time their influence on governmental decisions is not perceptible."

"Even in times of war, you can see current events in their historical perspective, provided that your passion for the truth prevails over your bias in favor of your own nation."

"I sometimes have the feeling that I have lived through all this before and, in a sense, I have. I was sixteen years old when the first World War broke out, and I lived at that time in Hungary. From reading the newspapers in Hungary, it would have appeared that, whatever Austria and Germany did was right and whatever England, France, Russia, or America did was wrong. A good case could be made out for this general thesis, in almost every single instance. It would have been difficult for me to prove, in any single instance, that the newspapers were wrong, but somehow, it seemed to me unlikely that the two nations located in the center of Europe should be invariably right, and that all the other nations should be invariably wrong. History, I reasoned, would hardly operate in such a peculiar fashion, and it didn't take long until I began to hold views which were diametrically opposed to those held by the majority of my schoolmates."

"Even if we accept, as the basic tenet of true democracy, that one moron is equal to one genius, is it necessary to go a further step and hold that two morons are better than one genius?"

"A man's clarity of judgment is never very good when you're involved, and as you grow older, and as you grow more involved, your clarity of judgment suffers."

"All we had to do was lean back, turn a switch and watch a screen of a television tube. If flashes of light appeared on the screen it would mean that liberation of atomic energy would take place in our lifetime. We turned the switch, saw the flashes — we watched for about five minutes — then switched everything off and went home. That night I knew the world was headed for trouble."

"Science is progressing at such a rapid rate that when you make a prediction and think you are ahead of your time by 100 years you may be ahead of your time by 10 at most."

"In life you must often choose between getting a job done or getting credit for it. In science, the most important thing is not the ideas you have but the decision which ones you choose to pursue. If you have an idea and are not doing anything with it, why spoil someone else's fun by publishing it?"

"It is not necessary to succeed in order to persevere. As long as there is a margin of hope, however narrow, we have no choice but to base all our actions on that margin. America and Russia have one interest in common which may override all their other interests: to be able to live with the bomb without getting into an all-out war that neither of them wants."

"A great power imposes the obligation of exercising restraint, and we did not live up to this obligation. I think this affected many of the scientists in a subtle sense, and it diminished their desire to continue to work on the bomb."

"In order to succeed it is not necessary to be much cleverer than other people. All you have to do is be one day ahead of them."

"The most important step in getting a job done is the recognition of the problem. Once I recognize a problem I usually can think of someone who can work it out better than I could."

"Suppose Germany had developed two bombs before we had any bombs. And suppose Germany had dropped one bomb, say, on Rochester and the other on Buffalo, and then having run out of bombs she would have lost the war. Can anyone doubt that we would then have defined the dropping of atomic bombs on cities as a war crime, and that we would have sentenced the Germans who were guilty of this crime to death at Nuremberg and hanged them? But, again, don't misunderstand me. The only conclusion we can draw is that governments acting in a crisis are guided by questions of expediency, and moral considerations are given very little weight, and that America is no different from any other nation in this respect."

"A scientist's aim in a discussion with his colleagues is not to persuade, but to clarify."

"I'm looking for a market for wisdom."

"If we focus our attention on the next twenty-five years we may say that development is likely to reach some point intermediate between the first bomb detonated over Hiroshima and processes which once initiated might put an end to all life on earth. Just what intermediate point will be reached within twenty-five years no one can tell."

"Another explanation for the failure of logic and observation alone to advance medicine is that unlike, say, politics, which uses a form of logic – mathematics – as its natural language, biology does not lend itself to logic. Leo Szilard, a prominent physicist, made this point when he complained that after switching from physics to biology he never had a peaceful bath again. As a physicist he would soak in the warmth of the bathtub and contemplate a problem, turn it in his mind, reason his way through it. But once he became a biologist, he constantly had to climb out of the bathtub to look up a fact."

"While in Kyoto I tried to learn Japanese with a vengeance. I worked much harder at it, and got to a point where I could go around in taxis and do things. I took lessons from a Japanese man every day for an hour. One day he was teaching me the word for "see." "All right," he said. "You want to say, 'May I see your garden?' What do you say?" I made up a sentence with the word that I had just learned. "No, no!" he said. "When you say to someone, 'Would you like to see my garden?' you use the first 'see.' But when you want to see someone else's garden, you must use another 'see,' which is more polite." "Would you like to glance at my lousy garden?" is essentially what you're saying in the first case, but when you want to look at the other fella's garden, you have to say something like, "May I observe your gorgeous garden?" So there's two different words you have to use. Then he gave me another one: "You go to a temple, and you want to look at the gardens..." I made up a sentence, this time with the polite "see." "No, no!" he said. "In the temple, the gardens are much more elegant. So you have to say something that would be equivalent to 'May I hang my eyes on your most exquisite gardens?" Three or four different words for one idea, because when I'm doing it, it's miserable; when you're doing it, it's elegant. I was learning Japanese mainly for technical things, so I decided to check if this same problem existed among the scientists. At the institute the next day, I said to the guys in the office, "How would I say in Japanese, 'I solve the Dirac Equation'?" They said such-and-so. "OK. Now I want to say, 'Would you solve the Dirac Equation?' — how do I say that?" "Well, you have to use a different word for 'solve,' " they say. "Why?" I protested. "When I solve it, I do the same damn thing as when you solve it!" "Well, yes, but it's a different word — it's more polite." I gave up. I decided that wasn't the language for me, and stopped learning Japanese."

"Years ago, when I was an assistant professor of physics at Berkeley, I used to be invited down to Cal Tech about once a year to give a talk. It was usually the low point of my year. In the audience at Cal Tech were two leaders of modern physics, Murray Gell-Mann and Richard Feynman, who interrupted with frequent questions, ruthlessly probing to see if I really knew what I was talking about and had anything new to say. Of the two, Feynman was the more frightening. Gell-Mann was mostly interested in finding out whether there was anything in my talk that he should know about, so he was no problem if I did have anything worth while to say. Feynman was having fun. It is Feynman as a fun-lover - chum of Las Vegas showgirls, cracker of safes at Los Alamos, player of bongo drums - who has won the hearts of the public. I found this side of Feynman hard to take. But, of course, Feynman had a more serious side. He did not do his great work on the quantum theory of fields in a moment between bongo gigs, but over several years of hard intellectual labour. On a more personal level, while helping to design the atomic bomb at Los Alamos during the war, Feynman devotedly nursed his first wife through her tragic and ultimately fatal illness. And Feynman thought deeply about the goals and methods of science, as shown in his 1964 Messenger lectures at Cornell."

"The story that Dick Feynman could open safes whose combinations had been forgotten by their owners is true."

"He hated the fact that he participated in the invention of nuclear weapons, and he doubly hated the fact that he had so much fun doing it."

"When I say he didn't like philosophy I meant he didn't like a certain style of thinking that was full of jargon, full of - I'll use his word - "baloney", where people who didn't know what they were talking about pontificated and used fancy words - like "ontological", which I never knew what that meant - as a substitute for simple thinking. That is what he didn't like. And yet, I think in some ways, in some deep way, he was an extraordinarily philosophical person."

"Several conversations that Feynman and I had involved the remarkable abilities of other physicists. In one of these conversations, I remarked to Feynman that I was impressed by Stephen Hawking's ability to do path integration in his head. "Ahh, that's not so great", Feynman replied. "It's much more interesting to come up with the technique like I did, rather than to be able to do the mechanics in your head." Feynman wasn't being immodest, he was quite right. The true secret to genius is in creativity, not in technical mechanics."

"In the hall, there were 183 new freshmen and a bowling ball hanging from the three-story ceiling to just above the floor. Feynman walked in and, without a word, grabbed the ball and backed against the wall with the ball touching his nose. He let go, and the ball swung slowly 60 feet across the room and back — stopping naturally just short of crushing his face. Then he took the ball again, stepped forward, and said: "I wanted to show you that I believe in what I'm going to teach you over the next two years.""

"An honest men, the outstanding intuitionist of our age, and a prime example of what may lie in store for anyone who dares to follow the beat of a different drum."

"Feynman is becoming a real pain in the ass."

"My strongest memory of [Feynman’s junior quantum mechanics course] is the very beginning, when he started, not with some deep principle of nature, or some experiment, but with a review of Gaussian integrals. Clearly, there was some calculating to be done. I did get over my shyness one time, to ask him about the infinities that appear in quantum field theory (QFT): do they have a physical interpretation? Feynman said ‘no.’ In retrospect, he must have known more, from the work of Wilson, Weinberg, and others. But perhaps it did not satisfy him, since he had not derived it himself. But this question tugged on me for the next eight years, and was my first deep result."

"Feynman's IQ was measured at 124 when he was young — well above average, but far from genius level. So how'd he become fluent in differential equations by the age of 15? Feynman's fascination with the inner workings of the mechanical objects around him couldn't have hurt his left-brain power. As a kid living in Queens, he took apart everything from radios to wagon wheels. This wide-eyed fascination stuck with him; for his entire life, Feynman's colleagues cited his "childlike" approach to physics problems, which bore great results. In fact, a fellow physicist once said that the “Feynman Problem Solving Algorithm” contained three steps: 1. Write down the problem. 2. Think very hard. 3. Write down the answer."

"He is by all odds the most brilliant young physicist here, and everyone knows this. He is a man of thoroughly engaging character and personality, extremely clear, extremely normal in all respects, and an excellent teacher with a warm feeling for physics in all its aspects. He has the best possible relations both with the theoretical people of whom he is one, and with the experimental people with whom he works in very close harmony.The reason for telling you about him now is that his excellence is so well known, both at Princeton where he worked before he came here, and to a not inconsiderable number of "big shots" on this project, that he has already been offered a position for the post war period, and will most certainly be offered others. I feel that he would be a great strength for our department, tending to tie together its teaching, its research and its experimental and theoretical aspects. I may give you two quotations from men with whom he has worked. Bethe has said that he would rather lose any two other men than Feynman from this present job, and E.P. Wigner said, "He is a second Dirac. Only this time human.""

"In science, as well as in other fields of human endeavor, there are two kinds of geniuses: the “ordinary” and the “magicians.” An ordinary genius is a fellow that you and I would be just as good as, if we were only many times better. There is no mystery as to how his mind works. Once we understand what he has done, we feel certain that we, too, could have done it. It is different with the magicians. They are, to use mathematical jargon, in the orthogonal complement of where we are and the working of their minds is for all intents and purposes incomprehensible. Even after we understand what they have done, the process by which they have done it is completely dark. They seldom, if ever, have students because they cannot be emulated and it must be terribly frustrating for a brilliant young mind to cope with the mysterious ways in which the magician's mind works. Richard Feynman is a magician of the highest caliber. Hans Bethe, whom Dyson considers to be his teacher, is an “ordinary genius”; so much so that one may gain the erroneous impression that he is not a genius at all. But it was Feynman, only slightly older than Dyson, who captured the young man's imagination."

"Even when Richard didn't understand, he always seemed to understand better than the rest of us. And whatever he understood, he could make others understand as well. Richard made people feel like children do when a grown-up first treats them as adults. He was never afraid to tell the truth, and however foolish your question was, he never made you feel like a fool."

"Feynman's grasp of the big picture, coupled with his love for knowing first-hand of practical details — from low-level programming to lock-picking — gave him an almost unique perspective on any subject he chose to study. It was this mastery, both of the minutiae of a subject and of its overall intellectual framework, that gave him the seemingly effortless ability to move back and forth between the two levels at will, without getting lost in the detail or losing the overall plot."

"Feynman was fond of saying that all of quantum mechanics can be gleaned from carefully thinking through the implications of this single experiment, so it's well worth discussing."

"Once I asked him to explain to me, so that I can understand it, why spin-1/2 particles obey Fermi-Dirac statistics. Gauging his audience perfectly, he said, "I'll prepare a freshman lecture on it." But a few days later he came to me and said: "You know, I couldn't do it. I couldn't reduce it to the freshman level. That means we really don't understand it.""

"Shortly before midnight on February 15, 1988, his body gasped for air that the oxygen tube could not provide, and his space in the world closed. An imprint remained: what he knew, how he knew."

"Architect of quantum theories, brash young group leader on the atomic bomb project, inventor of the ubiquitous Feynman diagram, ebullient bongo player and storyteller, Richard Phillips Feynman was the most brilliant, iconoclastic, and influential physicist of modern times. He took the half-made conceptions of waves and particles in the 1940s and shaped them into tools that ordinary physicists could use and understand. He had a lightning ability to see into the heart of the problems nature posed."

"A [physics student] ... discovers unpublished lecture notes by Richard Feynman, circulating samizdat style. He asks Gell-Mann about them. Gell-Mann says no, Dick's methods are not the same as the methods used here. The student asks, well, what are Feynman's methods? Gell-Mann leans coyly against the blackboard and says, Dick's method is this. You write down the problem. You think very hard. (He shuts his eyes and presses his knuckles parodically to his forehead.) Then you write down the answer."

"He surrounded himself with a cloud of myth, and he spent a great deal of time and energy generating anecdotes about himself. ... Many of the anecdotes arose, of course, through the stories Richard told, of which he generally was the hero, and in which he had to come out, if possible, looking smarter than anyone else."