Nobel Laureates In Physics

"The final lines are not mine: they come from an experiment on soft matter, after Boudin… An English translation might run like this:"

"A dense film of a conventional surfactant is quite impermeable. On the other hand, a dense film of Janus grains always has some interstices between the grains, and allows for chemical exchange between the two sides; "the skin can breathe". This may possibly be of some practical interest."

"While I am certainly not asking you to close your eyes to the experiences of earlier generations, I want to advise you not to conform too soon and to resist the pressure of practical necessity. Free imagination is the inestimable prerogative of youth and it must be cherished and guarded as a treasure."

"The Nobel Prize in Physics 1952 was awarded jointly to Felix Bloch and Edward Mills Purcell "for their development of new methods for nuclear magnetic precision measurements and discoveries in connection therewith""

"Le vrai point d'honneur [d'un scientifique] n'est pas d'être toujours dans le vrai. Il est d'oser, de proposer des idées neuves, et ensuite de les vérifier."

"Benjamin Franklin performed a beautiful experiment using surfactants; on a pond at Clapham Common, he poured a small amount of oleic acid, a natural surfactant which tends to form a dense film at the water-air interface. He measured the volume required to cover all the pond. Knowing the area, he then knew the height of the film, something like three nanometers in our current units. This was to my knowledge the first measurement of the size of molecules. In our days, when we are spoilt with exceedingly complex toys, such as nuclear reactors or synchrotron sources, I particularly like to describe experiments of this Franklin style to my students. Surfactants allow us to protect a water surface, and to generate these beautiful soap bubbles, which are the delight of our children."

"Of course, if electrons were waves there would be no difficulty. We think we understand the regular reflection of light and of x-rays--and we should understand the reflec- tion of electrons as well if electrons were only waves instead of particles. This observation though true does not seem a particularly valuable one. It is rather as if one were to see a rabbit climbing a tree, and were to say, "Well, that is rather a strange thing for a rabbit to be doing, but after all there is really nothing to get excited about. Cats climb trees --so that, if the rabbit were only a cat, we would understand its behavior perfectly." Of course, the explanation might be that what we took to be a rabbit was not a rabbit at all, but was actually a cat. Is it possible that we are mistaken about electrons? Is it possible that we have been wrong all this time in supposing that they are particles, and that actually they are waves? Well, 1 do not need to enumerate to you the many reasons we have for believing--I may say for knowing--that electrons are actually particles."

"Discoveries in physics are made when the time for making them is ripe, and not before."

"In the past century, and even nowadays, one could encounter the opinion that in physics nearly everything had been done. There allegedly are only dim 'cloudlets' in the sky or theory, which will soon be eliminated to give rise to the 'theory of everything'. I consider these views as some kind of blindness. The entire history of physics, as well as the state of present-day physics and, in particular, astrophysics, testifies to the opposite. In my view we are facing a boundless sea of unresolved problems."

"I am not a supporter of Marxism, but I fully agree with this formulation. Another thing is that opium can sometimes be useful, and its use justified. For example, I envy believers. Indeed, I am 86 years old, I understand that death is close. And it can turn out to be painful, and no less painful are thoughts about the fate of loved ones. How good it would be to believe in the existence of, say, an afterlife, etc. But the mind is given to man in order to control his emotions and not engage in self-deception, belief in miracles."

"Every physicist (naturally, this equally applies to other specialities, but I restrict myself to physicists for definitiveness) should simultaneously know, apart from theoretical physics, a wealth of facts from different branches of physics and be familiar with the newest notable accomplishments."

"Physics is a wrong tool to describe living systems."

"The constant questioning of our values and achievements is a challenge without which neither science nor society can remain healthy."

"Not only mesons are interesting..."

"The benefits of science are not only material ones. The truths that science teaches are of common interest the world over. The language of science is universal, and is a powerful force in bringing the peoples of the world closer together."

"The ideal student would be one who was not working for grades but was working because he was interested in the work and not trying to compete with fellow students."

"... Carl Anderson told me what life was like after he got his Ph.D. under Millikan in 1930. Dirac had proposed the existence of a partner to the electron, its antiparticle, and Carl wanted to find it by converting γ-rays found in the debris of cosmic rays into what we now call electron-positron pairs. He needs to get a big magnet, and build a cloud chamber with a lead plate and camera. When he asks Millikan for money, Millikan reaches into his pocket and gives him some. Carl goes to a couple of junk shops for supplies and gets to work. When the magnet, cloud chamber, and camera are finished, Carl puts them, together with food and a sleeping bag, into his old Model T Ford, and drives up the unpaved Mount Wilson Observatory road into the San Gabriel Mountains behind Pasadena. Carl is on his way to discovering the positron."

"I see a tremendous amount of intricacy in the world and we have probably only begun to scratch at the surface of its intricacy."

"The atom can't be seen, yet its existence can be proved. And it is simple to prove that it can't ever be seen. It has to be studied by indirect evidence — and the technical difficulty has been compared to asking a man who has never seen a piano to describe a piano from the sound it would make falling downstairs in the dark."

":: If you can draw one, but don't, then your audience won't know what you are talking about."

"Ultimately, progress in applications is not deterministic, but opportunistic, exploiting for new applications whatever new science and technology happen to be coming along."

"Whenever I teach my semiconductor device physics course, one of the central messages I try to get across early is the importance of energy band diagrams. I often put this in the form of "Kroemer's Lemma of Proven Ignorance":"

"The principal applications of any sufficiently new and innovative technology always have been—and will continue to be—applications created by that technology."

"You have to get a little untrapped from too much prior knowledge."

"Si on veut faire quelque chose, il faut donc s'occuper d'éducation."

"There are many examples in physics showing that higher precision revealed new phenomena, inspired new ideas, or confirmed or dethroned well-established theories."

"Whenever I came to him (Fritz Sauter) with a pure physics idea, he would invariably say, with slight sarcasm: "But Mr. Kroemer, you ought to be able to formulate this mathematically! " If I came to him with a math formulation, I would get, in a similar tone: "But Mr. Kroemer, that is just math, what is the physics?" After a few encounters of this kind, you got the idea: You had to be able to go back and forth with ease. Yet, in the last analysis, concepts took priority over formalism, the latter was simply an (indispensable) means to an end."

"History of science played a very important role for me. Before I knew well how to do an experiment, I knew why Joliot has missed the neutron, why his wife missed the fission, why they succeeded in having artificial radioactivity, and even why they almost missed the other things, by doing very nice experiments, but didn't come to the conclusion. That is science. Science is doubt, is research. It is not something which is – and that is the danger of teaching – which is too academic and which the people explain you it is like the logic thing that comes out of the computer, which is not true. You have intuition, you have passion."

":: If, in discussing a semiconductor problem, you cannot draw an Energy Band Diagram, this shows that you don't know what you are talking about,"

"I feel that very rarely have I done any work in my life. I have a good time. I'm exploring. I'm playing a game, solving puzzles, and having fun, and for some reason people have been willing to pay me for it. Officially, I was supposed to retire years ago, but retire from what? Why stop having a good time?"

"It's a fantastically specialized universe, but how in the world did it happen?"

": with the corollary"

"I am impressed by the great limitations of the human mind. How quick are we to learn, that is, to imitate what others have done or thought before. And how slow to understand, that is, to see the deeper connections. Slowest of all, however, are we in inventing new connections or even in applying old ideas in a new field."

"Doing physics is much more enjoyable than just learning it. Maybe 'doing it' is the right way of learning, at least as far as I am concerned."

"A gifted experimentalist, and theoretician, in the best Newtonian tradition... His contributions to quantum measurements, and elucidative teachings on quantum mechanics, have not yet received the attention they deserve."

"In fact, there really is not a new law of nature. It was all in the theory to begin with but nobody worked it out."

"A rare theorist turned experimentalist."

"At the first of the 1960's Rochester Coherence Conferences, I suggested that a license be required for use of the word photon, and offered to give such license to properly qualified people."

"I liked quantum mechanics very much. The subject was hard to understand but easy to apply to a large number of interesting problems."

"You should look at all the experimental information at hand, not only the most relevant, and be prepared to make conjectures if that helps."

"If we fight a war and win it with H-bombs, what history will remember is not the ideals we were fighting for but the methods we used to accomplish them. These methods will be compared to the warfare of Genghis Khan, who ruthlessly killed every last inhabitant of Persia."

"Together with Peierls, he developed a theory of the deuteron in 1934 which he extended in 1949. He resolved some contradictions in the nuclear mass scale in 1935. He studied the theory of nuclear reactions in 1935-1938, predicting many reaction cross sections. In connection with this work, he developed Bohr's theory of the compound nucleus in a more quantitative fashion. This work and also the existing knowledge on nuclear theory and experimental results, was summarized in three articles in the Reviews of Modern Physics which for many years served as a textbook for nuclear physicists."

"Creativity makes life valuable. Man is the sole creator; he stands out from the swarming masses of petty little folks. It doesn't matter what kind of creativity it is - whether scientific or socio-political - it's of equal value."

"In his 1930 book, Dirac took for granted that measurements could be made, but was very vague about what was actually involved."

"We have more nuclear warheads than the Russians, and I consider this to be the most important measure of relative strength. In addition, as Dr. Kissinger stressed many years ago, at the present level of strategic armaments superiority in numbers or megatons has no meaning."

"Neither Dirac nor von Neumann discussed his measurements in physical terms."

"When investigating theories at the tiniest conceivable scales in nature, almost all researchers today revert to the quantum language, accepting the verdict from the Copenhagen doctrine that the only way to describe what is going on will always involve states in HIlbert space, controlled by operator equations."

"The usual no-go theorems telling us that hidden variables are irreconcilable with locality, appear to start with fairly conventional pictures of particle systems, detectors, space and time. Usually, it is taken for granted that events at one place in the universe can be described independently from what happens elsewhere. Perhaps one has to search for descriptions where the situation is more complex. Maybe, it needs not be half as complex as superstring theory itself. The conventional Copenhagen interpretation of quantum mechanics suffices to answer all practical questions concerning conventional experiments with quantum mechanics, and the outcome of experiments such as that of Aspect et al can be precisely predicted by conventional quantum mechanics. This is used by some to state that no additional interpretation prescriptions for quantum mechanics are necessary. Yet we insist that the axioms for any "complete" quantum theory for the entire cosmos would present us with as yet unresolved paradoxes."

"In practice, quantum mechanics merely gives predictions with probabilities attached. This should be considered as a normal and quite acceptable feature of predictions made by science: different possible outcomes with different probabilities. In the world that is familiar to us, we always have such a situation when we make predictions. Thus the question remains: What is the reality described by quantum theories? I claim that we can attribute the fact that our predictions come with probability distributions to the fact that not all relevant data for the predictions are known to us, in particular important features of the initial state."

"... trying to solve a paradox will lead to new kinds of understanding. And I think that the problem of subjecting black holes to quantum mechanics is a fundamental paradox of the same nature, and the same depth, and the same importance as the paradox that Max Planck was studying at the beginning of the twentieth century."