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Replies: 15   Last Post: Feb 22, 2013 9:04 AM

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Pentcho Valev

Posts: 5,016
Registered: 12/13/04
Posted: Dec 9, 2012 1:58 PM
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Conférence de M. Jean-Marc LEVY-LEBLOND, Université de Nice, mercredi 9 janvier 2013 à 17H30, amphithéâtre Fresnel, Institut de physique, 5, rue de l'Université à Strasbourg: "La lumière va-t-elle toujours à la même vitesse? Mais pourquoi aurait-elle ce privilège? Et quel rapport avec la théorie de la relativité einsteinienne? Ne peut-on donc ralentir ou accélérer les photons?"

Mais c'est du révisionnisme! La question "Ne peut-on donc ralentir ou accélérer les photons?" est extrêmement dangereuse pour Einsteiniana. La réponse est évidente:
"Le principe d'équivalence, un des fondements de base de la relativité générale prédit que dans un champ gravitationnel, la lumière tombe comme tout corps matériel selon l'acceleration de la pesanteur."
University of Illinois at Urbana-Champaign: "Consider a falling object. ITS SPEED INCREASES AS IT IS FALLING. Hence, if we were to associate a frequency with that object the frequency should increase accordingly as it falls to earth. Because of the equivalence between gravitational and inertial mass, WE SHOULD OBSERVE THE SAME EFFECT FOR LIGHT. So lets shine a light beam from the top of a very tall building. If we can measure the frequency shift as the light beam descends the building, we should be able to discern how gravity affects a falling light beam. This was done by Pound and Rebka in 1960. They shone a light from the top of the Jefferson tower at Harvard and measured the frequency shift. The frequency shift was tiny but in agreement with the theoretical prediction."
Dr. Cristian Bahrim: "If we accept the principle of equivalence, we must also accept that light falls in a gravitational field with the same acceleration as material bodies."
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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