In “The Ultimate Einstein” by Donald Goldsmith, and speaking of Einstein’s miracle year, the author write:
"Finally, near the end of the year, Einstein published a paper entitled “Does an Object’s Inertia Depend on Its Energy Content?” This work, an elucidation of part of his special-relativity theory, showed that mass and energy are essentially interconvertible. Einstein wrote, using v to denote the speed of light: “…if an object gives up an amount of energy L in the form of radiation, it’s mass will grow smaller by L/v2.”
“In its more familiar form with m for mass, E for energy, c for the speed of light, and both sides of this relationship multiplied c2, we have the world’s most famous equation: E = mc2.”
Which is nice, but who first penned “the world’s most famous equation” E=mc2
(Sadly the 2’s didn’t superscipt as they did when I wrote this post in WORD. but you get the meaning.)
As revealed in an episode of Family Guy, someone showed up at the patent office where Einstein was working, trying to patent the idea, and Einstein promptly killed him and took credit for the discovery.
In all seriousness, Einstein wasn’t alone in developing the theory. There’s some evidence that his wife at the time helped him with it, and one other researcher (who’s name escapes me) had essentially done everything Einstein had done, but hadn’t wrapped it up in a simple formula like Einstein.
Einstein may not have “coined the phrase”. I can’t say who did it first, but I do know that we call the special relativisitic coordinate transformations “Lorentz Transformations” because Lorentz worked out all the math well before Einstein. We give Einstein credit for special relativity because he was the first to realize it was the truth, and not just a mathematical exercise in data fitting. And that was no small thing–it took guts to say “time isn’t what you think it is.”
I don’t know exactly when the terminology changed. Even David Bodanis’ book E=MC[sup]2[/sup] uses that formula even when referring to the original paper. But the change in terminology doesn’t mean that someone else came up with the equation. Einstein did.
You’re probably thinking of Lorentz. One can fairly say that the idea of Special Relativity was “ripe”, and that if Einstein hadn’t developed it, someone else would have in fairly short order. But as it happened, Einstein was the first to follow the ideas to their logical conclusion.
The equation first appeared in print as “E=mc[sup]2[/sup]” in a long review article by Einstein: “On the Relativity Principle and the Conclusions Drawn from It”, Jahrbuch der Radioaktivitat und Elektronik4 (1907) 411-62. Despite the apparent publication date, the issue didn’t actually come out until 22nd January 1908.
Incidentally, it’s of interest given his role in the Nazi-era promotion of Deutsch Physik, the editor who invited Einstein to write the review was Johannes Stark, who at this stage was willing to encourage the new theory.
That “oddly” has been mildly niggling at me overnight. I think there’s a rather plausible chain of events explaining why there isn’t an English translation until that in The Principle of Relativity (Methuen, 1923), which is the translation by Perrett and Jeffery of the 4th edition of Das Relativitatsprinzip (1922).
In the years immediately following the original 1905 appearences, any research physicist wanting to read the papers could have been expected to be able to read them in German. Annalen der Physik was one of the world’s leading research journals and any good university library of the period in Britain or the US would have subscribed. Researchers would also have been able to ask Einstein for offprints of the individual papers.
As interest in the theory grew, it must have became useful to reissue them along with additional material in the original edition of Das Relativitatsprinzip in 1913. (Not to be confused with the book of the same name by Max von Laue published a couple of years earlier.) This included stuff like the text of Minkowski’s 1908 lecture on space-time, which probably had been harder for people to get hold of. This was evidently a successful idea and there was a 3rd (expanded) edition by 1920.
Now it may well have occured to someone to translate this collection into English at about this stage. But WWI erupts. British and German scientists break off all direct contact. No British publisher would have been able to negotiate the rights for the duration of the war.
After the Armistice, two factors come into play. The Allied scientific establishments continued to boycott contacts with Germany into the 1920s, so there was little general call for translations from German. Einstein was regarded as an exception to this policy, partly because his public anti-war statements during the conflict meant that he wasn’t perceived as being tainted with German militarism. Though he himself was unwilling to be singled out in this way, prefering to appeal for an immediate resumption of scientific relations.
The other, probably more obvious, factor is that Einstein becomes a world celebrity in November 1919. In London, Methuen quickly sign up the rights to his pop science book Relativity and rush that out in 1920. I’d expect that it was partly the success of this that prompts them to try the altogether far more technical The Principle of Relativity in the market in 1923.
No oddly inexplicable delay in this chain of events.
As a comparison, Einstein’s most successful citation classic in English has actually been the Brownian motion paper from 1905. That didn’t appear in translation until 1926 - in another collection published by Methuen.
And if you want to experimet with the implications of this equation, go to: www.1728.com/einstein.htm
You’ll learn that the Hiroshima blast was the equivakent of converting one gram of matter into energy.
Antiochus
If you don’t want to bother with superscripts for squares and cubes, go here: www.1728.com/altchar.htm
and you’ll learn that holding the ALT key and pressing 253 will produce ², so you can make the “official looking”
Just to clarify my point, I was certainly aware that a knowledge of German and a European education was de rigueur for anyone with pretenses to be a scientist of almost any stripe in that era.
Still, while the Great War was an obstacle, Einstein himself managed to get the General theory published in the middle of it. And since an English expedition did the eclipse observations in 1919 that confirmed the theory an additional three-year gap is a long time.
But you’re quite right in pointing out that our English-centric world is a more recent development that we should be aware of when we go back even a century in time.
Just out of curiosity why would any publisher be concerned about copyright during a war? I confess I do not know the legalities of it all but it seems if you are at war with another country you are well set to rip off anything of theirs you want with little worries they will be seeking you out to sue you.
The first thing to be said is that, as far as I can make out from Bartocci’s paper on De Pretto (in Italian), the claim is technically irrelevant to the issue raised by the OP. The key passage in De Pretto’s paper is apparently:
It seems that De Pretto is using m for mass, but v instead of c and is largely expressing the proposed relationship in words rather than as an equation. So, regardless of the physics, this isn’t an instance of “E=mc[sup]2[/sup]” appearing in the famous form before the 1907/8 Jahrbuch example.
More generally, there’s never been the claim - at least amongst those with a knowledge of the background history - that Einstein was the first to suggest that there was some relationship between mass and energy. There had been a lot of work done on the notion of electromagnetic mass before 1905: even in pre-SR versions of electromagnetism, charged particles can appear to become heavier as they are accelerated. People were thus interested in whether much, or even all, of the mass of ions and electrons moving in the might actually be electromagnetic energy. Poincare and others had suggested that mass and energy might be interchangable, without being able to quantify the exact relation. Amongst such investigations - and indeed in other areas - you find equations from before 1905 that are very like Einstein’s. From what I gather from Bartocci’s paper (and I don’t read Italian), De Pretto was speculating in the context of ether theory. That someone happens to have stumbled onto Einstein’s formula, despite working with an unconvincing physical foundation, isn’t that surprising. Bartocci seems aware of some of this, but I’m unsure exactly what grasp he has of the nuances.
As for the suggestion that Einstein read De Pretto’s paper, I’d be prepared to bet that De Pretto’s argument has nothing in common with Einstein’s 1905 derivation of the relationship.
Without anything more substantial, De Pretto’s just one footnote - amongst many, many others - in the background to the invention of SR.
I’ll note one side effect of the fact that people had speculated about mass-energy before Einstein: it wasn’t immediately obvious what the implications of E=mc[sup]2[/sup] were in SR. The 1905 paper only derived the relation in one, rather special, case and so it was an open question for a while how universally it applied. Planck was dissatisfied with the argument, even while accepting SR, and quickly proposed what he thought was a better one. At one point in those early days, Stark actually attributed the mass-energy equivalence result to Planck rather than Einstein. (Given his later, nonsensical attacks on the latter, I should say that Stark’s assessment at the time seems to have been honest and involved no animus towards Einstein.) The big Jahrbuch review was, in part, Einstein clarifying the significance of the equivalence. Along with others, he continued to publish different proofs of the result through to about 1910 to continue to drive home the idea that the relation should be universal and not restricted to special cases.
Einstein’s main papers founding GR appeared in Annalen der Physik and the proceedings of the Berlin Academy. Neither journal was being received during the war by university libraries in Britain, so the normal mechanism whereby they would be read there had been broken off. However, de Sitter specifically sent these papers to Eddington from neutral Holland. De Sitter also wrote an article on the subject for one of the British journals. So while direct contact between Britain and Germany had broken down completely, a little amount was being sent in an as hoc fashion via third parties.
I’m not sure it’s that long. Even if it is significant, one can think of other reasons for a delay of a few years. Mentuen may have initially thought the whole business was a fad, with the money to be made in rushing out original popularisations rather than in translating a set of reprints.
The Berne Convention dates back to 1886, so there were already international copyright agreements in place. There’s also the factor, already mentioned in the earlier post, that the various academic national communities were boycotting each other. The potential audience in Britain didn’t want to have anything to do with anything Germanic.
Eddington’s an unusual exception. From a Quaker background, he was pretty anti- the war himself. That’s partly why he’s the one who has the channel via de Sitter and who’s the one who pushed for the 1919 expedition.
However, it seems you have delved deeper into the matter and found the assertion to be not as well-founded as that article claims.
I’ll agree that DePretto should be relegated to the footnote department.
Well, with that matter settled, I notice you have carefully avoded Johnny L.A.'s assertion that “… the whole theory was devised by an African-German lesbian.”
That claim is a little tougher to discredit than Mr De Pretto’s isn’t it?
It doesn’t. E = mc[sup]2[/sup] is from Special Relativity; Lambda doesn’t show up until the more complicated General Relativity (and even there, only in a modified form of GR). The Famous Equation is not the sum total of Einstein’s work; indeed, it’s only a small offshoot of the lesser of his two great theories.
The central equation of General Relativity is G = 8piT . Boldface is here used to represent tensors, and of course there’s a lot more work that goes into just what those tensors mean. Roughly speaking, G (the Einstein Tensor) is a tensor which describes the curvature of spacetime, and T (the Stress-Energy Tensor) is a tensor which describes the distribution of mass and energy. This is the equation where Lambda shows up: If GR is modified to include the Cosmological Constant, then Einstein’s equation reads G = 8piT + Lambda*g. Lower-case g is a different tensor, the Metric Tensor, which also relates to curvature (but in a different way), and Lambda is a constant. The cosmological constant (or something much like it) is back in vogue, but there’s some difference of opinion as to whether to consider it part of the “curvature” side of the equation, or part of the “stuff” side.
[/sub]