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Pentcho Valev

Posts: 6,212
Registered: 12/13/04
Posted: Jan 22, 2013 7:05 AM
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Exceeding the speed of light without actually exceeding it:
"Dr Michio Kaku reveals how we really could one day build a warp drive and set out on our own star trek."

Needless to say, Michio Kaku just practices doublethink:
George Orwell: "Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously, and accepting both of them. (...) ...with the lie always one leap ahead of the truth."

When did doublethink start in Einsteiniana? From the very beginning: Einstein's 1905 papers implied that the speed of light both depends and does not depend on the speed of the light source:
Relativity and Its Roots, 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."

The lie (the speed of light does not depend on the speed of the light source) was all along one leap ahead of the truth (the speed of light depends on the speed of the light source) so the truth only showed up two times in Einstein's writings - in 1909 and in 1954:
Albert Einstein (1909): "A large body of facts shows undeniably that light has certain fundamental properties that are better explained by Newton's emission theory of light than by the oscillation theory. For this reason, I believe that the next phase in the development of theoretical physics will bring us a theory of light that can be considered a fusion of the oscillation and emission theories."
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."

Clues showing that the departure from the field concept of light is tantamount to a departure from Einstein's 1905 light postulate and an adoption of the variable speed of light predicted by Newton's emission theory of light:
"The two first articles (January and March) establish clearly a discontinuous structure of matter and light. The standard look of Einstein's SR is, on the contrary, essentially based on the continuous conception of the field."
"And then, in June, Einstein completes special relativity, which adds a twist to the story: Einstein's March paper treated light as particles, but special relativity sees light as a continuous field of waves."

Doublethink nowadays:
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."

Pentcho Valev

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