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Pentcho Valev

Posts: 6,212
Registered: 12/13/04
Posted: Apr 22, 2013 1:03 AM
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Bingo the Einsteiniano makes career and money by advocating Newton's emission theory of light (which says that the speed of photons varies with both the speed of the emitter and the gravitational potential, like the speed of ordinary projectiles):
Jean Eisenstaedt: "At the end of the 18th century, a natural extension of Newton's dynamics to light was developed but immediately forgotten. A body of works completed the Principia with a relativistic optics of moving bodies, the discovery of the Doppler-Fizeau effect some sixty years before Doppler, and many other effects and ideas which represent a fascinating preamble to Einstein relativities. It was simply supposed that 'a body-light', as Newton named it, was subject to the whole dynamics of the Principia in much the same way as were material particles; thus it was subject to the Galilean relativity and its velocity was supposed to be variable. Of course it was subject to the short range 'refringent' force of the corpuscular theory of light --which is part of the Principia-- but also to the long range force of gravitation which induces Newton's theory of gravitation. The fact that the 'mass' of a corpuscle of light was not known did not constitute a problem since it does not appear in the Newtonian (or Einsteinian) equations of motion. It was precisely what John Michell (1724-1793), Robert Blair (1748-1828), Johann G. von Soldner (1776-1833) and François Arago (1786-1853) were to do at the end of the 18th century and the beginning the 19th century in the context of Newton's dynamics. Actually this 'completed' Newtonian theory of light and material corpuscle seems to have been implicitly accepted at the time. In such a Newtonian context, not only Soldner's calculation of the deviation of light in a gravitational field was understood, but also dark bodies (cousins of black holes). A natural (Galilean and thus relativistic) optics of moving bodies was also developed which easily explained aberration and implied as well the essence of what we call today the Doppler effect. Moreover, at the same time the structure of -- but also the questions raised by-- the Michelson experiment was understood. Most of this corpus has long been forgotten. The Michell-Blair-Arago effect, prior to Doppler's effect, is entirely unknown to physicists and historians. As to the influence of gravitation on light, the story was very superficially known but had never been studied in any detail. Moreover, the existence of a theory dealing with light, relativity and gravitation, embedded in Newton's Principia was completely ignored by physicists and by historians as well. But it was a simple and natural way to deal with the question of light, relativity (and gravitation) in a Newtonian context."
Einstein and the Changing Worldviews of Physics, Einstein Studies, 2012, Volume 12, Part 1, 23-37, The Newtonian Theory of Light Propagation, Jean Eisenstaedt: "It is generally thought that light propagation cannot be treated in the framework of Newtonian dynamics. However, at the end of the 18th century and in the context of Newton's Principia, several papers, published and unpublished, offered a new and important corpus that represents a detailed application of Newton's dynamics to light. In it, light was treated in precisely the same way as material particles. This most interesting application - foreshadowed by Newton himself in the Principia - constitutes a relativistic optics of moving bodies, of course based on what we nowadays refer to as Galilean relativity, and offers a most instructive Newtonian analogy to Einsteinian special and general relativity (Eisenstaedt, 2005a; 2005b). These several papers, effects, experiments, and interpretations constitute the Newtonian theory of light propagation. I will argue in this paper, however, that this Newtonian theory of light propagation has deep parallels with some elements of 19th century physics (aberration, the Doppler effect) as well as with an important part of 20th century relativity (the optics of moving bodies, the Michelson experiment, the deflection of light in a gravitational field, black holes, the gravitational Doppler effect). (...) A relativistic optics of moving bodies: a corpuscle of light is subject to Galilean kinematics, and thus to its principle of relativity as well as to the corresponding theorem of the addition of velocities. (...) Not so surprisingly, neither the possibility of a Newtonian optics of moving bodies nor that of a Newtonian gravitational theory of light has been easily "seen," neither by relativists nor by historians of physics; most probably the "taken-for-granted fact" of the constancy of the velocity of light did not allow thinking in Newtonian terms."
Alberto Martinez: "Does the speed of light depend on the speed of its source? Before formulating his theory of special relativity, Albert Einstein spent a few years trying to formulate a theory in which the speed of light depends on its source, just like all material projectiles. Likewise, Walter Ritz outlined such a theory, where none of the peculiar effects of Einstein's relativity would hold. By 1913 most physicists abandoned such efforts, accepting the postulate of the constancy of the speed of light. Yet five decades later all the evidence that had been said to prove that the speed of light is independent of its source had been found to be defective."
John Norton: "These efforts were long misled by an exaggeration of the importance of one experiment, the Michelson-Morley experiment, even though Einstein later had trouble recalling if he even knew of the experiment prior to his 1905 paper. This one experiment, in isolation, has little force. Its null result happened to be fully compatible with Newton's own emission theory of light. Located in the context of late 19th century electrodynamics when ether-based, wave theories of light predominated, however, it presented a serious problem that exercised the greatest theoretician of the day."
John Norton: "In addition to his work as editor of the Einstein papers in finding source material, Stachel assembled the many small clues that reveal Einstein's serious consideration of an emission theory of light; and he gave us the crucial insight that Einstein regarded the Michelson-Morley experiment as evidence for the principle of relativity, whereas later writers almost universally use it as support for the light postulate of special relativity. Even today, this point needs emphasis. The Michelson-Morley experiment is fully compatible with an emission theory of light that CONTRADICTS THE LIGHT POSTULATE."
"Relativity and Its Roots" by Banesh Hoffmann: "Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether."
Albert Einstein Institute: "One of the three classical tests for general relativity is the gravitational redshift of light or other forms of electromagnetic radiation. However, in contrast to the other two tests - the gravitational deflection of light and the relativistic perihelion shift -, you do not need general relativity to derive the correct prediction for the gravitational redshift. A combination of Newtonian gravity, a particle theory of light, and the weak equivalence principle (gravitating mass equals inertial mass) suffices. (...) The gravitational redshift was first measured on earth in 1960-65 by Pound, Rebka, and Snider at Harvard University..."

Pentcho Valev

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