Lorentz and Poincare were holding to — or, at least, not clearly breaking from — the idea of a “real” cosmic-coordinate system, in which light was propagated in a stationary ether.Lorentz and Poincare never said that there was a cosmic coordinate system, Einstein never said that there was no cosmic coordinate system, and there is no explanation of why the issue would have any physical significance.

while he (Lorentz) was attempting to make sense of his experimental results with the concept of “local time,” Einstein understood that these and other results were a reflections of the very nature of time.Lorentz and Einstein did use slightly different terminology. Lorentz used “local time” in 1895. Einstein’s 1905 term was “time of the stationary system”. Einstein’s 1905 time used the same definitions and formulas as had been previously used by Lorentz and Poincare. Einstein did not understand that time was the fourth dimension and that time can be understood to have a geometrical relationship to the three spatial dimensions. That is one of the chief lessons of special relativity, and Einstein missed it entirely.

Do you know who first brought attention to that 1905 article? It was Max Planck.Yes, Planck was the journal editor who accepted the paper, and he wrote a couple of relativity papers himself. Maybe he was even partial to German scientists. But he never said that Einstein's work was any better than that of Lorentz and Poincare.

Let’s take a look at the first paragraph ... “It is known that Maxwell’s electrodynamics ...”The asymmetry was described in common textbooks and was solved by Lorentz transformations. That is why they are called Lorentz transformations and not Einstein transformations.

Einstein is being gracious when he says that that asymmetry is “known.” He was the only person on Earth who was bothered by it.

Lorentz: ... “I did not indicate the transformation which suits best. That was done by Poincaré and then by Mr. Einstein and Minkowski....”Yes, Lorentz credited Poincare over Einstein. So did everyone else who read Poincare.

Lorentz: “[T]he chief difference [is] that Einstein simply postulates what we have deduced,...”Yes, that is the chief difference between Einstein's 1905 paper and the previous published papers of Lorentz and Poincare.

“Poincaré’s reaction to Einstein’s 1905 paper was rather strange. When Poincaré lectured in Göttingen in 1909 on relativity he did not mention Einstein at all...”To a mathematician like Poincare, postulating someone else's theorems is a trivial thing to do. Poincare had no need to cite someone who merely postulated a result in an expository paper; he would cite the man who actually proved it previously.

Poincare: “Perhaps … we should construct a whole new mechanics, of which we only succeed in catching a glimpse, where inertia increasing with the velocity, the velocity of light would become an impassable limit....”That is what Poincare said in his 1904 St. Louis lecture, and he was exactly correct. Relativity was the new mechanics.

The most striking thing about these pro-Einstein arguments is how the Einstein idolizers are dogmatically persistent with insubstantial arguments. I don't blame John as he is just repeating the conventional wisdom of the Einstein fans. They use phrases like “greatest physicist that ever lived” based largely on the originality of the 1905 relativity paper, and yet they cannot point to any formula, mathematical argument, or physical consequence that was new. They base their idolotry entirely in insubstantial arguments about minor differences in terminology, and a belief that no one could have been as smart as Einstein.

Roger --

ReplyDeleteI fear you're doing yourself more harm than good by taking seriously the remarks of an admitted layman -- me -- who struggles with even an elementary understanding of this subject; nevertheless, thank you.

I imagine you're familiar with remarks by a man named Olivier Darrigol, whose identity and credentials I don't know. At http://www.bourbaphy.fr/darrigol2.pdf is a 2005 paper he delivered to the "Poincare Seminar." Does your book have anything to say about Darrigol's remarks therein?

John (Bonaccorsi)

My book addresses the strongest arguments for Einstein's priority that I could find. I even attack some famous physicists. Darrigol wrote two articles on the matter, and they are among the better sources. He is very specific about crediting Poincare for many aspects of relativity. I comment on his articles in the book, and in July 2007, Aug. 2008, Sept. 2009, and Dec. 2009.

ReplyDeleteIn that 2005 paper, Darrigol credits Poincare with much -- but let's look at a few things:

ReplyDelete1 -- At page 14, after a review of some reasoning that Poincare put forth in 1905 and thereafter, Darrigol says:

"For any one familiar with Einstein's theory of relativity, this reasoning seems very odd. Indeed, the light ellipsoid corresponds to a fixed value of the time t in one reference frame and to space measured in another frame. In general, Poincare's theory allows for the use of the 'true time' in any reference system, whereas our relativity theory regards this sort of mixed reference as a

mathematical fiction. This means that the conceptual basis of Poincare's theory is not compatible with Einstein's, even though both theories are internally consistent and have the same empirical

predictions (for the electrodynamics of moving bodies)."

2 -- Darrigol's footnote to the above is this:

"The empirical equivalence of the two theories simply results from the fact that any valid reasoning of Einstein's theory can be translated into a valid reasoning of Poincare's theory by arbitrarily calling the time, space, and fields measured in one given frame the true ones, and calling all other determinations apparent."

3 -- At page 18, after a synopsis of Einstein's first 1905 paper, Darrigol says:

"Most of the components of Einstein's paper appeared in others' anterior works on the electrodynamics of moving bodies. Poincare and Alfred Bucherer had the relativity principle. Lorentz and Larmor had most of the Lorentz transformations, Poincare had them all. Cohn and Bucherer rejected the ether. Poincare, Cohn, and Abraham had a physical interpretation of Lorentz's local time. Larmor and Cohn alluded to the dilation of time. Lorentz and Poincare had the relativistic dynamics of the electron. None of these authors, however, dared to reform the concepts of space

and time. None of them imagined a new kinematics based on two postulates. None of them derived the Lorentz transformations on this basis. None of them fully understood the physical implications

of these transformations. It all was Einstein's unique feat.

4 -- Darrigol concludes, at page 22, as follows:

Thus, Einstein was neither the first nor the last contributor to relativity theory. He learned much by reading the best authors of his time, and he partly duplicated results already obtained by

Lorentz and Poincare. Yet there is no doubt that his papers of 1905 marked a dramatic turn in our understanding of space, time, mass, and energy. His questioning of received ideas was most radical. His construction of alternative theories was most elegant, powerful, and durable. By rejecting the ether and propounding a new chronogeometry, he prepared the ground for further intellectual achievements, including general relativity and quantum theory."

I'll continue in a separate comment.

(Continued from comment 1:18 PM:)

ReplyDeleteLet's say that Einstein's first paper of 1905 is, in some sense, equivalent to what Poincare had done. Maybe we could put it this way:

Poincare says that if you're looking out your window at a car that's parked outside your house, the length you take that car to be is its length -- it's "true" length. If the car starts driving away from your house, it's length will appear to you to change; the difference between its true length and its apparent length, while it's moving, may be calculated via the Lorentz transformation.

Einstein, on the other hand, says that neither of those lengths is the "true" length. He agrees that the lengths will differ by an amount calculable via the Lorentz transformation, but he draws no distinction between what we might call "true" length and "observed" length. In his conceptual scheme, all length is observed length -- nothing more or less.

Similarly, Poincare notes -- or, at least, senses -- that time as measured by a person in that car will be different from that of a person who is, say, at rest relative to the street along which the car is moving. Einstein says the same, but he denies that either measurement of time is any more "real" than the other; moreover, he doesn't concern himself with the question whether either corresponds to time as measured by an observer at rest relative to a stationary ether. Poincare, on the other hand, still thinks that there is some "real" time -- i.e., time as measured by an observer at rest in the either, even though he acknowledges that no such real time can be identified.

I'll continue with a third comment.

(Continued from comment of 1:33 PM:)

ReplyDeleteIf Einstein had gone no further than his first 1905 paper, it might -- might -- be reasonable to say that Poincare and he had said the same thing. The difference between their schemes could be characterized -- maybe -- as a mere "difference in terminology," as you have it.

Is that true? I think not. Einstein's first paper is a beginning -- in which he has accomplished an extraordinary thing: he has completed Newton's effort to eliminate subjectivism (for lack of a better term). Since the Greeks, the apparent difference between the behavior of objects near Earth and objects such as the Sun and the moon -- "in the sky" -- had been a conundrum. How are those objects "floating" up there -- and how are they just moving around on their own? How come they're not like objects on Earth, where things fall and where things have to be pushed to move? After two thousand years, Newton resolved that with the concept of universal gravitation. He said, in effect, "Don't you see? If you were living on the moon, the Earth is what would seem to be floating?"

That changed everything.

I'll continue in what I hope will be a final comment.

(Continued from comment of 1:44 PM:)

ReplyDeleteWith his first 1905 paper, Einstein has completed Newton's effort. He has done for time what Newton did for space. Is the speed of light as measured on its transit from Jupiter to Earth the "real" speed of light? Do we have to consider whether Jupiter and Earth are in motion relative to each other? Do we have to consider whether either or both of them are in motion relative to a stationary ether, whose coordinates we can never identify? No, we don't. The speed of light is simply that: the speed of light. It doesn't change -- and what we mean by time is connected to it.

Yes -- if Einstein had stopped there, we might -- might -- be able to say he'd gone no further than Poincare; but within a few months, he is able to go further -- precisely because his conception of the subject is different from Poincare's. If two billiard balls, a and b, are traveling at the same velocity, v, and strike each other obliquely, their joint momentum is conserved -- BUT, Einstein observes, their post-collision momentum will not necessarily be equal. The momentum of each of them will be dependent on the observer's motion relative to them; indeed, each of the billiard balls will measure the post-collision momentum of the other differently. Thus does Einstein recognize the equivlance of mass and energy. Did Poincare make that leap? Not to my knowledge.

Before long, Einstein has extended his insight to accelerating objects. Is a man who drops out of an airplane accelerating toward Earth? Not from the man's perspective. Do the astronauts who train for zero gravity by floating around in those aircraft feel that they are "in motion." They certainly do not. By recognizing this (long before such training in airplanes was taking place), Einstein extends his original relativistic insight to a reformulation of gravitation; extraordinarily, he recognizes that time varies not only with an oberver's motion but with an observer's position in a gravitational field. Whether Poincare had some intimation of this, I don't know; he didn't see it fully, as far as I'm aware. Not even close.

It doesn't matter whether Minkowski and Hilbert helped with the math. It doesn't even matter whether Poincare laid the groundwork for Minkowski's spacetime math (as, for all I know, he might have). It certainly doesn't matter whether Einstein was "vain" or an "egomaniac," as you presume to say, in the July 2007 comment you linked in response to my first comment, above. (I confess I have an instinctive aversion to such comments on the character of another person -- particularly a person whom one "knows" only at second hand, at best.) Einstein is the one who conceived it all.

This is my layman's understanding of the matter.

PS I am troubled to see that in a couple of places in my comment of 1:33 PM, I wrote "it's" for "its." As I age, I find myself regularly making such elementary mistakes -- "their" for "there," for example.

ReplyDeletePPS I've just taken a look at your additional comments about Darrigol (i.e., your comments of August 2008 and of September and December 2009). I'm not sure you've really resolved things in favor of Poincare. That's because I'm not sure what Poincare is saying when he says it doesn't matter whether the ether exists. Does that mean he doesn't think there is some sort of stationary reference frame that underlies the cosmos and in relation to which, an object may be said to be either moving or at rest? I don't know. Maybe he doesn't. If he doesn't, I'm not sure he's found the best way to communicate that -- even to himself. Maybe that's why he wasn't able to draw the further conclusions, about the equivalence of energy and mass and of acceleration and gravitation. If he did, in fact, draw either of those conclusions, I haven't heard of it; but then again, I'm certainly not thoroughly informed on this.

ReplyDeleteJohn, you are still arguing that Einstein had some superior understanding of time, even tho Darrigol's papers make it clear that Poincare had a better understanding of time, and had it years earlier. You even quote Darrigol saying that Einstein's understanding was deficient. Your argument hinges on saying that "Poincare ... still thinks that there is some 'real' time ... even though he acknowledges that no such real time can be identified."

ReplyDeleteThat is, in order to credit Einstein, you have to assume that Poincare thought something contrary to what he actually said. Are you a mindreader? How would you get such knowledge? Do you have your own personal theories about how other scholars should not get credit for what they said because they did not understand what they said, or even believed the opposite of what they said?

To be honest, Roger, I'm now wondering whether you're right. Let's say, for the sake of discussion, that Einstein's first 1905 paper was equivalent to Poincare's relativity work. Was Einstein's next step -- to the equivalence of mass and energy -- and his further step -- to the equivalence of acceleration and gravitation and thus (I guess) to a relationship between gravitation and time -- not quite significant? At the Occidental Observer, you acknowledged that the latter step was, as far as you know, his own. I don't know your thoughts about the former (mass and energy).

ReplyDeleteI don't expect you to go into detail, when you're offering for sale a book on the subject; but if you would care to respond in any way to my question, I'll be pleased to read your answer.

John, I say that Einstein's first 1905 paper was

ReplyDeleteinferiorto Poincare's relativity work. Poincare's work is bolder, more correct, more rigorous, more original, more honest, more advanced, more influential, and closer to our modern understanding of relativity. But I am all in favor of crediting Einstein for his original work. It is harder to figure out what was original in Einstein's case, because he did not credit his sources. Lorentz and Poincare are very straightforward about saying what they did.If you don't mind, Roger, I'm going to throw in another thought. Poincare, as you surely know, wrote a piece called "The Measure of Time." An English translation is at http://en.wikisource.org/wiki/The_Measure_of_Time It's the source of the following sentence, which one often sees quoted:

ReplyDelete"We have not a direct intuition of simultaneity, nor of the equality of two durations."

As you know, I haven't even the mathematical aptitude of a person with an undergraduate mathematics degree from a middling college; but I have to say that every time I read that, I find myself being annoyed. As Poincare indicates near the essay's beginning, recognition that we have no direct intuition of the equality of two intervals of time is commonplace. What I find annoying is that Poincare throws no new light on the subject, even though he discourses on it for quite some time. He never has the strength of penetration to identify what is meant by an interval of time. He makes some slight pass at the question, when he talks about comparison of the beats of a metronome with a revolution of the earth -- but even then, he's talking about comparing the length of time of two successive revolutions. He's comparing intervals, as if he and we know what is meant by "interval." He remarks that "the temperature, the resistance of the air, the barometric pressure, make the pace of the pendulum vary," as if he and we know what is meant by "vary." "Vary" in relation to what? He's assuming the very thing he has correctly acknowledged can't be known: identity of intervals. (If we can't know whether two intervals are the same, how can we tell that a metronome's intervals are varying?)

In that whole essay, in other words, Poincare never attains the height of clarity that Einstein attains with a single pair of sentences in Section 1 (in Part I) of the first 1905 paper. Those sentences, which, as you know, I quoted at the Occidental Observer, are as follows:

"We have to take into account that all our judgments in which time plays a part are always judgments of simultaneous events. If, for instance, I say, "That train arrives here at 7 o’clock," I mean something like this: "The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events."

That knocks me out. I can't help wondering whether that is more important than the 1905 paper's (possible) equivalence with the relativity work of Poincare. It's as if Einstein, with lightning clarity, has begun his exploration of the problem at its true starting point -- a point nobody else ever identified. Starting there, he proceeds clearly, along the path to the Lorentz transformations and then, over the course of a decade, to general relativity. Because he has approached the problem in a way that Poincare never did, he is able to go farther than Poincare ever did. Why does he have to mention Poincare? When he reaches the Lorentz transformations, he refers to them by name -- a name given to them by Poincare, I think I've read. What more do you want him to say?

I'll continue in a separate comment.

(Continued from my comment of 11:15 PM:)

ReplyDeleteAnd really, I think it's something even a little more than that -- something I have difficulty formulating. It's as if Einstein, by postulating relativity and the constancy of light, is putting things in proper logical sequence. I keep looking at the conclusion of another sentence, in Section 9 (in Part II) of the 1905 paper:

"[W]e have the proof that, on the basis of our kinematical principles, the electrodynamic foundation of Lorentz’s theory of the electrodynamics of moving bodies is in agreement with the principle of relativity."

If Poincare's relativity work and Einstein's paper were really equivalent, that sentence would have no place in Einstein's paper. There is some sense -- at least, in Einstein's mind, evidently -- in which Lorentz's work, as previously presented, is not properly situated with respect to the principle of relativity. Why else would he (Einstein) have felt the need to demonstrate that "the .. foundation of Lorentz's theory ... is in inagreement with the principle of relativity"? He, Einstein, is reorienting the discussion.

As always, my thoughts and questions are those of a pitiable layman.

Roger -- I've just seen your comment of 11:10 PM. Somehow, my 11:15 PM comment -- which I'd thought had posted -- has disappeared. I'll try to reconstruct it in a comment immediately after the present one.

ReplyDeleteI can't respond to the first part of your 11:10 comment. I simply don't have the mathematical or scientific aptitude to say whether Poincare's work, in comparison with Einstein's, is "bolder, more correct, more rigorous, more original, more honest, more advanced, more influential, and closer to our modern understanding of relativity." Maybe it is -- and if it is, there's probably nothing much else to say. On the other hand, I'm troubled when you say, casually, that you're "in favor of crediting Einstein for his original work." To my ear, at least, that trivializes the general theory of relativity. I'm also bothered by your statement that it's "harder to figure out what was original in Einstein's case, because he did not credit his sources." Maybe he felt he didn't have any sources.

I'll try to reconstruct my vanished post of 11:15.

(Here's my reconstruction -- far from exact -- of what I posted at 11:15:)

ReplyDeletePoincare, as you surely know, wrote a piece called "The Measure of Time." An English translation of it is at http://en.wikisource.org/wiki/The_Measure_of_Time The piece's final section is the source of the following sentence, which one often sees quoted:

"We have not a direct intuition of simultaneity, nor of the equality of two durations."

Though I don't have even the mathematical aptitude of a person with an undergraduate mathematics degree from a middling college, that sentence always annoys me. Early in the piece, Poincare correctly indicates that it is widely recognized that we have no direct intuition of the equality of two intervals of time. What annoys me is that he throws no new light on the subject, even though he discourses on it for some time. He never has the clarity of mind to identify what is meant by an interval of time. He makes some slight pass at the subject when he discusses comparison of the beats of a metronome with the revolution of the Earth; but even then, he's comparing the length of two successive revolutions. He's talking about comparison of intervals, as if he and we know what is meant by "interval." He remarks that "the temperature, the resistance of the air, the barometric pressure, make the pace of the pendulum vary." He's assuming what he has just said can't be known: identity of intervals. (If we can't know whether intervals are identical, how can we know that the intervals of the metronome are varying?)

I compare that with the astonishing clarity of a pair of sentences from Section 1 (in Part I) of Einstein's 1905 paper. The sentences, which, as you know, I quoted at the Occidental Observer, are these:

"We have to take into account that all our judgments in which time plays a part are always judgments of simultaneous events. If, for instance, I say, 'That train arrives here at 7

o’clock,' I mean something like this: 'The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events.'"

That seems to me to be starting the discussion at its true starting point -- which nobody else ever identified. Having thus approached the subject from the right spot, Einstein proceeds to the Lorentz transformations and, over the course of a decade, to the general theory of relativity. Because he has approached the subject in the right way, he is able to go farther than Lorentz ever did.

(Well -- maybe my 11:15 PM comment will eventually resurface, but I guess the above is close enough.)

John, I am sorry about comments being lost. It appears to be a Google bug. I have lost a couple of comments myself. I think that this is your 11:15 post.

ReplyDelete--

If you don't mind, Roger, I'm going to throw in another thought. Poincare, as you surely know, wrote a piece called "The Measure of Time." An English translation is at http://en.wikisource.org/wiki/The_Measure_of_Time It's the source of the following sentence, which one often sees quoted:

"We have not a direct intuition of simultaneity, nor of the equality of two durations."

As you know, I haven't even the mathematical aptitude of a person with an undergraduate mathematics degree from a middling college; but I have to say that every time I read that, I find myself being annoyed. As Poincare indicates near the essay's beginning, recognition that we have no direct intuition of the equality of two intervals of time is commonplace. What I find annoying is that Poincare throws no new light on the subject, even though he discourses on it for quite some time. He never has the strength of penetration to identify what is meant by an interval of time. He makes some slight pass at the question, when he talks about comparison of the beats of a metronome with a revolution of the earth -- but even then, he's talking about comparing the length of time of two successive revolutions. He's comparing intervals, as if he and we know what is meant by "interval." He remarks that "the temperature, the resistance of the air, the barometric pressure, make the pace of the pendulum vary," as if he and we know what is meant by "vary." "Vary" in relation to what? He's assuming the very thing he has correctly acknowledged can't be known: identity of intervals. (If we can't know whether two intervals are the same, how can we tell that a metronome's intervals are varying?)

In that whole essay, in other words, Poincare never attains the height of clarity that Einstein attains with a single pair of sentences in Section 1 (in Part I) of the first 1905 paper. Those sentences, which, as you know, I quoted at the Occidental Observer, are as follows:

"We have to take into account that all our judgments in which time plays a part are always judgments of simultaneous events. If, for instance, I say, "That train arrives here at 7 o’clock," I mean something like this: "The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events."

That knocks me out. I can't help wondering whether that is more important than the 1905 paper's (possible) equivalence with the relativity work of Poincare. It's as if Einstein, with lightning clarity, has begun his exploration of the problem at its true starting point -- a point nobody else ever identified. Starting there, he proceeds clearly, along the path to the Lorentz transformations and then, over the course of a decade, to general relativity. Because he has approached the problem in a way that Poincare never did, he is able to go farther than Poincare ever did. Why does he have to mention Poincare? When he reaches the Lorentz transformations, he refers to them by name -- a name given to them by Poincare, I think I've read. What more do you want him to say?

Yes, Roger, what you just posted -- at 12:18 AM, March 29 -- was my 11:15 post. Thank you.

ReplyDeleteJohn, you might like Einstein's explanation better. Several years later, textbooks appeared that explained relativity better than that. Modern textbooks are even better.

ReplyDeleteYes, one of Einstein's main conclusions was to make Lorentz's 1895 theory fully compatible with the relativity principle. Lorentz did not prove it himself until his 1904 paper, and Einstein claimed to have not seen that paper. Not everyone believes Einstein.

You say, "Maybe he felt he didn't have any sources." Obviously Einstein had sources. You can read any of the Einstein biographies for info about that. Even his admirers agree that he was dishonest about his sources. He did succeed in tricking a lot of people into thinking that he paper was more original than it was. But it also means that you cannot trust anything he says.

Roger -- thank you for your reply. Thank you, too, for hearing me out. I have certainly profited from this exchange. I'm sure I'll be revisiting this blog, which treats subjects I find very interesting, even if my grasp of them is very limited.

ReplyDelete