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The trend for debunking science's simple narratives can be overdone, says Philip Ball.
There was once a time when the history of science was told as a succession of Eureka moments in which strokes of experimental or theoretical genius led the scales to fall from our eyes, banishing old, false ideas to the dustbin.
Posted by Nicola Jones on September 07, 2007
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In the article, Eddington's Quaker beliefs are cited as a possible source for wishing to bend the truth in the cause of peace. However as a member of the Religious Society of Friends I feel this is unlikely as we live by a Truth testimony that requires us to tell the truth even when it is detrimental to do so. So I feel this theory is unlikely.
Posted by: Jason Kilburn Evans | September 8, 2007 09:47 AM
WERE EINSTEIN AND EDDINGTON INNOCENT?
http://philipball.blogspot.com/2007/09/arthur-eddington-was-innocent-this-is.html
"One of the more recent victims of this revisionism is the ‘confirmation’ of Einstein’s theory of general relativity offered in 1919 by the British astronomer Arthur Eddington, who reported the predicted bending of light in observations made during a total ecplise. Eddington, it has been said, cooked his books to make sure that Einstein was vindicated over Newton, because he had already decided that this must be so. This idea has become so widespread that even physicists who celebrate Einstein’s theory commonly charge Eddington with over-interpreted his data. In his Brief History of Time, Stephen Hawking says of the result that “Their measurement had been sheer luck, or a case of knowing the result they wanted to get.” Hawking reports the widespread view that the errors in the data were as big as the effect they were meant to probe. Some go further,saying that Eddington consciously excluded data that didn’t agree with Einstein’s prediction. Is that true? According to a study by Daniel Kennefick, a physicist at the University of Arkansas [1], Eddington was in fact completely justified in asserting that his measurements matched the prediction of general relativity. Kennefick thinks that anyone now presented with the same data would have to share Eddington’s conclusion......With the technology then available, measuring the bending of starlight was very challenging. And contrary to popular belief, Newtonian physics did not predict that light would remain undeflected – Einstein himself pointed out in 1911 that Newtonian gravity should cause some deviation too. So the matter was not that of an all-or-nothing shift in stars’ positions, but hinged on the exact numbers. The results from the two locations were conflicting. It has been claimed that those at Sobral showed little bending, and thus supported Newton, whereas those at Principe were closer to Einstein’s predictions. The case for prosecuting Eddington is that he is said to have rejected the former and concentrated on the latter."
Presented in this way the story is a red herring. It camouflages the fact that the bending of light is due to the variability of the speed of light in a gravitational field - a fact Einstein confirmed in his 1920 "Relativity":
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
"Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory. In the 1920 book "Relativity: the special and general theory" he wrote: ". . . according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [. . .] cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position." Since Einstein talks of velocity (a vector quantity: speed with direction) rather than speed alone, it is not clear that he meant the speed will change, but the reference to special relativity suggests that he did mean so."
After the 1919 glory Einstein and Eddington should have returned to Einstein's 1911 equation c'=c(1+V/c^2) showing how the speed of light varies with the gravitational potential:
http://www.physlink.com/Education/AskExperts/ae13.cfm
"So, it is absolutely true that the speed of light is _not_ constant in a gravitational field [which, by the equivalence principle, applies as well to accelerating (non-inertial) frames of reference]. If this were not so, there would be no bending of light by the gravitational field of stars....Indeed, this is exactly how Einstein did the calculation in: 'On the Influence of Gravitation on the Propagation of Light,' Annalen der Physik, 35, 1911. which predated the full formal development of general relativity by about four years. This paper is widely available in English. You can find a copy beginning on page 99 of the Dover book 'The Principle of Relativity.' You will find in section 3 of that paper, Einstein's derivation of the (variable) speed of light in a gravitational potential, eqn (3). The result is,
c' = c0 ( 1 + V / c^2 )
where V is the gravitational potential relative to the point where the speed of light c0 is measured."
http://www.blazelabs.com/f-g-gcont.asp "The first confirmation of a long range variation in the speed of light travelling in space came in 1964. Irwin Shapiro, it seems, was the first to make use of a previously forgotten facet of general relativity theory -- that the speed of light is reduced when it passes through a gravitational field....Faced with this evidence, Einstein stated:"In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position."......Today we find that since the Special Theory of Relativity unfortunately became part of the so called mainstream science, it is considered a sacrilege to even suggest that the speed of light be anything other than a constant. This is somewhat surprising since even Einstein himself suggested in a paper "On the Influence of Gravitation on the Propagation of Light," Annalen der Physik, 35, 1911, that the speed of light might vary with the gravitational potential. Indeed, the variation of the speed of light in a vacuum or space is explicitly shown in Einstein's calculation for the angle at which light should bend upon the influence of gravity. One can find his calculation in his paper. The result is c'=c(1+V/c^2) where V is the gravitational potential relative to the point where the measurement is taken. 1+V/c^2 is also known as the GRAVITATIONAL REDSHIFT FACTOR."
Since Einstein's 1911 equation c'=c(1+V/c^2) is consistent with Newton's prediction of the bending of light, and since Einstein's 1915 new prediction was different from Newton's, Einstein and Eddington should have offered an equation different from c'=c(1+V/c^2) but consistent with Einstein's new prediction. They did not do so.
Pentcho Valev
pvalev@yahoo.com
Posted by: Pentcho Valev | September 17, 2007 09:05 AM
Newton's corpuscular model of light says light should be dealt with in terms of DISCONTINUOUS structures (photons), not in terms of CONTINUOUS fields (waves). It implies that the speed of light is VARIABLE and obeys the equations c'=c+v and c'=c(1+V/c^2), where c is the initial speed of photons relative to the light source, v is the relative speed of the light source and the observer (in the absence of a gravitational field), V is the gravitational potential difference between the point of emission and the point of observation of photons. Einstein knew all along that, as far as the speed of light is concerned, Newton's corpuscular model is correct, but found it suitable to admit this at the end of his life:
http://www.perimeterinstitute.ca/pdf/files/975547d7-2d00-433a-b7e3-4a09145525ca.pdf
Albert Einstein (1954): "I consider it entirely possible that physics cannot be based upon the field concept, that is on continuous structures. Then nothing will remain of my whole castle in the air, including the theory of gravitation, but also nothing of the rest of contemporary physics."
Pentcho Valev
pvalev@yahoo.com
Posted by: Pentcho Valev | September 18, 2007 10:49 AM
“…led the scales to fall from our eyes, banishing old, false ideas to the dustbin.” Nicola Jones. [editor's note: it was Philip Ball who wrote those words, not Nicola. Nicola just posted the blog comment.]
It’s that time again! (Discussions such as the above would now be good only for historians!) A century has unduly passed; so, without further ado, please do access (1) for perusal.
One can understand the scepticism and even cynicism at such pivotal moments in history, but what is unique here is the upfront monetary offer for a concept's refutation. See also the short article (2), the debunking of which would bring down the entire theory propounded. Good luck! (Remember, you would also be doing me a great favour – waking me up.)
Thank you and kind regards,
Eugene Sittampalam
(1) www.sittampalam.net/EinsteinLegacy.htm
(2) www.sittampalam.net/LateralThoughts.pdf
Posted by: Eugene Sittampalam | October 2, 2007 01:35 PM