Archives - Mathematics: Page 16
Author: paul carson (Fri Jul 14, 2006 3:07 am)
Title: Lost in Einstein’s Shadow
Einstein was a great physicist and also a great mathematician. I have taken the freedom to post these letters from the American Scientist magazine because of the relevance it has to the history of science. I would like to say that I am in agreement with Dr. Rothman about the fact that science is a product of the collective and interwoven work of many individuals and that that doesn’t take away the merit of the contribution of each individual scientist to their field. (Paul Carson)
By Tony Rothman from American Scientist (March-April, 2006)
The year of 1905 is remembered above all for relativity theory. As a result of a famously vague statement in Einstein’s own paper about “unsuccessful attempts to detect the motion of the Earth relative to the ‘light medium’”, pundits have long held that he was only dimly aware of the celebrated experiments that failed to reveal the mysterious medium –the ether – whose existence was synonymous with the “absolute space” implicit in classical physics. That is, sound waves travel in air, water waves travel in water; physicists naturally assumed that light required a medium in which to travel-the ether. The trouble was, a whole series of experiments designed to detect it turned up empty handed. It was these negative results that eventually led to relativity.
Did Einstein know about the vigorous search for ether? Well, in an 1899 letter to his fiancée, Mileva Maric, Einstein mentions that he’s written to renowned physicist Wilhelm Wein about Wein’s review of the ether experiments, and that he’s anxiously awaiting a replay. Einstein also read an 1895 paper in which Hendrik Lorentz (independently of two others) postulated his famous “Lorentz contraction” –that objects moving at high speed actually shrink. That paper was all about the ether experiments, and Lorentz introduced the contraction precisely to explain their failure.
Lorentz was no amateur. The Dutchman was considered the leading physicist of his generation, and soon he and his colleagues were waging a well published attack on the hypothetical ether and all its difficulties. In 1904 Lorentz tried to fix everything with his celebrated “transformations” that mixed up space and time in a way that –if true- would leave. Maxwellian electromagnetic theory intact but shake the foundations of Newton in physics.
Lorentz didn’t know why his transformations should be correct. With relativity Einstein provided the explanation, but shortly before his death, he claimed to have known only about Lorent’z 1895 paper, not the later one containing the transformations. Memory is often too good to be true. In Einstein’s very paper of 1905 he says, “we have thus shown that… the electrodynamic foundation of Lorentz’s theory… agrees with the principle of relativity”. This appears to be a direct reference to Lorentz’s 1904 work.
Principle of relativity. Einstein didn’t call his creation “the theory of relativity”, but it was indeed based on two postulates, the first being the “principle of relativity”, the supposition that any experiment done on a train moving with constant velocity should give the same result as an identical experiment done on the ground.
It wasn’t Einstein’s idea. The great French mathematician Henri Poincaré enunciated the principle of relativity at least as early as 1902 in his popular book Science and Hypothesis. We know from Einstein’s friend Maurice Solovine that the two pounced on Poincaré book, indeed that it kept them “breathless for weeks on end”. It should have. In Science and Hypothesis, Poincaré declares: “1)There is no absolute space, and we can only conceive of relative motion; 2)There is no absolute time. When we say that two periods are equal, the statements has no meaning; 3)Not only have we no direct intuition of the equality of two periods, but we have not even direct intuition of the simultaneity of two events occurring in two different places.”
These ideas lie at the heart of relativity, and it is hard to imagine that they did not have a profound effect on Einstein’s thinking. But Poincaré not only speculated –he calculated, and in the same weeks that Einsten was writing his paper on relativity, Poincaré completed a pair of his own. The major one is quite remarkable. Mathematically, he has more than Einstein does. Among other things, he notes that time can be viewed as a fourth dimension (something Einstein doesn’t do, by the way), he predicts the existence of gravitational waves 10 years before Einstein does and, perhaps most remarkable of all, he writes down an expression exactly equivalent to E=mc2 several months before his rival. But he fails to interpreted it.
Regarding Einstein
To the Editors:
Tony Rothman’s delightful essay “Lost in Einstein’s Shadow”, (Marginalia, March-April) depicts some able scientist who made genuine progress along two of the three lines that Albert Einstein subsequently made his own in 1905. it becomes clear that the reason for their eclipse was not that their achievements were small, but rather that Einstein’s definitive results were so all-encompassing. This may explain why there is no record of indignation among the eclipsed about their lack of credit. Indeed, at least Hendrik Lorentz formed a long and friendly relationship with Einstein. Occasionally seen indignation by third parties therefore rings false-just envious iconoclasm.
For physicists such as myself, with limited historical knowledge, there was one person (unmentioned in the essay) who was not eclipsed: Marian Smoluchwski, who independently found the relation between Brownian motion and the molecular structure of matter.
Perhaps the most remarkable omission from the essay is the topic of anyone even partially anticipating Einstein in his third line of research, the notion of localized energy packets that he called light quanta. Max Planck had introduced energy quanta almost as a bookkeeping device to account for the form of blackbody radiation, but Einstein made these quanta concrete by associating them with definite locations.
In this case it appears that no one was overshadowed, because no one except Einstein even tried to advance beyond Planck. It was Einstein’s most controversial proposal in 1905 and arguably the one that most shapes our world today. He thought of it as revolutionary, and the lack of precedents tends to vindicate his view.
In short, if some people deserve more credit than the community hs given them, still Einstein does not deserve less.
Alfred Scharff Goldhaber
State University of New York at Stony Brook
To the Editors:
Dr. Rothman’s thesis, that often one person is given too much credit for a scientific discovery while many others were close to the same discovery, is an almost universal truth. But the example he picked, Einstein, is a major exception.
In the case of special relativity, the work of James Clerk Maxwell, Isaac Newton and others was a prerequisite, but Einstein’s work was truly a breakthrough.
It is true that Lorentz and Henri Poincaré had derived equations identical to those of special relativity. It is also true that these two were geniuses. It is natural that they would derive correctly working equations after applying their significant talents to the subject for so many years and studying the prior theoretical and 3experimental work. It appears from their work that they had only a last conceptual step to bridge. But that last step was huge. So huge, in fact, that neither man understood it, even after they saw Einstein’s work. They both demonstrated their lack of understanding in works they published years after 1905.
Einstein’s theory seem obvious to those who were taught only it to begin with, so when we see brilliant theorists deriving the same equations and flirting with “local times”, we tend to think they were close to seeing the truth and assume the theory was virtually at hand. But with their lifetimes steeped in one paradigm, they simply could never have developed the correct concept. It took the truly revolutionary approach that Einstein achieved. For that and all his other accomplishments, he truly deserved the accolades he received during the year of physics.
Paul Dickson
Aiken, SC
Dr. Rothman responds:
It is nice to see that “Lost in Einstein’s Shadow” generated some interest. I must, however first distance myself from Zen Antoniak’s remarks in the May-June Letters section. Einstein was certainly the greatest scientist of the 20th century, if not of all time. His sins of omission in citing the work of colleagues are probably no greater than of many others scientist. I find it difficult to believe that an unknown 26-year-old patent clerk could sit in his office determining the future: “If I don’t reference Poincaré history will assign me all the credit.” Einstein’s sins of mission had large consequences than most only because in retrospect he turned out to be Einstein.
Dr. Goldhaber is certainly correct that I should have mentioned Smoluchowski, who formulated the theory of Brownian motion independently of Einstein, but who is nearly forgotten. His paper, though, only appeared in the 1906 Annalen der Physik, and, judging from his introductory remarks, it was Einstein’s paper that prodded Smoluchowski into publishing his own. Nut Smoluchowski is indeed a good example of a case where if Einstein hadn’t done something, someone else would have, and in fact already had.
Regarding Planck, I have always felt him well-honored for his creation of quantum mechanics. It is true that for the five years after Planck introduced his quantum hypothesis, no one besides Einstein took it seriously enough to see that it should be extended to include the concept of “light quanta” or, in other words, photons. Here, I do not think there has been any question of priority or influence, which is why I did not discuss it in the essay.
I am slightly less sympathetic with Dr. Dickson’s view. If he reads the essay carefully, he will see that I never claimed Lorentz or Poincaré invented relativity. Nevertheless, I think the evidence is clear that their work influenced Einstein, poincaré must be given credit for being the first to enunciate the principle of relativity, which he does in black and white, and for foreseeing that the speed of light would prove to be an impassable barrier. Furthermore, if one agrees that Poincaré’s equations give results identical to Einstein’s (and Poincaré does write down the correct” relativistic Lagrangian,” the quantity from which the equations of relativity follow), then I think one must concede the issue is one of interpretation. Einstein provide a profoundly simple interpretation that we today cannot imagine doing physics without. However, at a recent colloquium, I had the opportunity to ask Peter Galison, whose books Dr. Dickson uses as a source, what he thought of Poincaré’s failure to “nail it.”. he replied that if Einstein’s formulation had not paved the road for general relativity, we’d probably regard Einstein’s theory and Poincare’s as two ways of looking at the same thing.
Yes, we revere Einstein because his achievements were so all-encompassing, but neither should one think that he wrapped up everything in a blinding flash. There are mistakes in the 1905 relativity paper, including a serious conceptual error regarding the bending of starlight (“aberration”), one of the phenomena Einstein created his theory to explain. He also initially rejected Hermann Minkowski’s wedding of space and time (anticipated again by Poincaré) as “superfluous erudition.” All of which goes to show that science is, indeed, a collective endeavor and that science, like art, consist of far more than the few icons we are exposed to in concert halls or museums.
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