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I Galaxies are really moving?

  1. Feb 25, 2017 #1
    Are galaxies are really moving away.Or galaxies are stationary but space-time expends so galaxies move with it ? Or maybe they could be same thing ?
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  3. Feb 25, 2017 #2


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    Google "metric expansion". There is no (well, very little and for a different reason) proper motion of far distant galaxies with respect to the Earth, it's metric expansion.
  4. Feb 25, 2017 #3


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    This is a coordinate dependent statement. In "local" normal coordinates, galaxies are certainly moving away.
  5. Feb 25, 2017 #4
    Like here its metric expention I guess.Here galaxies are standing still but universe expends so galaxies are moving with a velocity.Galaxies are moving away with a velocity v but not for they have a speed itself,Space time carries galaxies ?
  6. Feb 26, 2017 #5
    Take a rubber belt and put 5-6 balls on it as if it's a kind of bead. Then pull the belt in opposite directions. You'll see the process itself.
  7. Feb 26, 2017 #6
    I understand..
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