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Theory on Light

  1. Aug 17, 2005 #1

    I have a theory about light: could our observations of light always travelling at 300 000 km/s be explained as the terminal velocity of light? When an object falls through the atmosphere it will eventually stop accelerating because the pressure of the atmosphere equals the pull of gravity. What if light is being pulled to the speed of 300 000 km/s by the gravity of the earth and a substance, perhaps the Cosmic Background Radiation, keeps it from accelerating past that?


  2. jcsd
  3. Aug 17, 2005 #2
    I'm not sure what you're asking. Is it "can light be accelerated?" Well, technically no. But it does gain momentum when falling into a gravity well, like the Earth's gravitational field. You see light always moves at the same speed to all observers.
  4. Aug 17, 2005 #3


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    Isn't the CBR... a form of light?
  5. Aug 17, 2005 #4
    No. As others have pointed out, concepts of acceleration and light do not mix. Our observation that light always travels at a set rate has been explained by the special theory of relativity.

    It is also important to note that the experiments showing light travels at a set rate were preceeded by Maxwell's theory of electromagnetism. According to Maxwell's theory of electromagnetism and the principle of relativity, light must always travel at c. I think it was Brian Greene who said, "No one has ever held a lump of light in their hands," clarifying the notion that light *must* travel at c to exist (this is explained by both Maxwell's theory and quantum mechanics and goes hand-in-hand with Einstein's special theory of relativity).
    Last edited: Aug 17, 2005
  6. Aug 17, 2005 #5


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    If you were right, then light would travel at different speeds perpendicular to the earth's surface than parallel to it. And it doesn't.
  7. Aug 18, 2005 #6


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    Last edited by a moderator: Apr 21, 2017
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