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There goes another relativity

  1. Mar 25, 2003 #1
    there goes another relativity!!!

    as some member stated:
    "the velocity of light is constant in vacuum"

    i wonder:

    "is it because the vacuum is all alike?"

    "would the velocity of light be constant in same kind of waters?"

    "would we have to define new theories for relativity then?"
  2. jcsd
  3. Mar 25, 2003 #2


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    I consider vacumn to be the absence of material particles (materials composed of atoms) so yes all vacumn is the same.

    Of course light takes more time to transit a given distance in the presence of atomic material. Haven't you read a single thread concerning this? There are many.

    Just like if you are dirving at 35km/h, it takes longer to go the same distance if you must stop a traffic lights every intersection then if there are no lights.

    The theory of Relativity was derived with the speed of light in vacumn constant as a fundamental postulate. The speed of light in materials does not have any effect on this.

    Be careful where you take this thread Dock!
  4. Mar 25, 2003 #3
    clarifying thought

    The principle of relativity by itself doesn't have to do anything with material(or absence of it) through which light travels. It simply(sic!) states that light travels with the constant velocity ( := c) in all frames of reference which move with constant speeds in respect to each other.
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