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Topic: DECALAGE D'EINSTEIN OU DE NEWTON ?
Replies: 1   Last Post: Nov 20, 2013 12:44 AM

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Pentcho Valev

Posts: 3,005
Registered: 12/13/04
DECALAGE D'EINSTEIN OU DE NEWTON ?
Posted: Nov 18, 2013 12:54 PM
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http://www.techno-science.net/?onglet=glossaire&definition=6628
"Le décalage d'Einstein est un effet prédit par les équations d'Albert Einstein. D'après cette théorie, un photon émis depuis un astre massif arrive décalé vers le rouge à cause des champs gravitationnels."

"Décalage de Newton" ne serait pas correct ?

http://www.einstein-online.info/spotlights/redshift_white_dwarfs
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..."

Evidemment "décalage de Newton" est correct ("décalage d'Einstein" ne l'est pas) mais dangereux:

http://courses.physics.illinois.edu/phys419/sp2013/Lectures/l13.pdf
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. Consider a light beam that is travelling away from a gravitational field. Its frequency should shift to lower values. This is known as the gravitational red shift of light."

http://bouteloup.pierre.free.fr/vulg/relge.pdf
"Considérons une fusée posée sur le sol terrestre, donc immobile dans un champ de gravitation. Déja, à cause du principe d'équivalence, la lumière tombe vers le bas avec la même accélération qu'un caillou, vue par un observateur immobile dans la fusée."

1. Si la lumière tombe vers le bas avec la même accélération qu'un caillou, alors sa vitesse varie selon l'équation

c' = c(1 + gh/c^2),

comme prédit par la théorie de l'émission de Newton et en contradiction avec la relativité générale.

2. Si la lumière tombe vers le bas avec la même accélération qu'un caillou, alors, en l'absence de gravitation, sa vitesse par rapport à l'observateur varie avec v, la vitesse de l'observateur, selon l'équation

c' = c + v,

comme prédit par la théorie de l'émission de Newton et en contradiction avec la relativité restreinte.

Pentcho Valev




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