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Gravities range

  1. Dec 1, 2009 #1
    How do we know that the force of gravitation continues indefinitely with respect to distance? Is there any evidence to support it? Could it be possible that it works on a large scale, but drops to zero at a certain distance much like other forces eg. strong nuclear?
  2. jcsd
  3. Dec 1, 2009 #2
    Hi there,

    It could certainly be. Therefore, you would need very, very, very far to see if you ideas could maybe work. Because, we just notice, by looking up in the sky, that the gravitational theroy seems to work even on larger scales, e.g. attraction between galaxies. Therefore, we could suppose that the mathematical model can be applied anywhere in the Universe.

  4. Dec 1, 2009 #3


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    At some distance 2 objects will no longer feel gravity from each other due to the expanding universe.
    That is if gravity travels at the speed of light. Others here can correct me if I am wrong here but at some point wouldn’t the speed of expansion exceed the speed of light. The expansion is cumulative isn’t it?
    If we know how much expansion there is in a given distance could we find the distance where the expansion exceeds the speed of light, and is this making any sense to anyone?
    I have been pondering this for some time now.
    Last edited: Dec 1, 2009
  5. Dec 1, 2009 #4
    But do we notice the furthest galaxy having an attraction on the furthest galaxy away from that one? Perhaps its only neighbouring galaxies that have any effect on each other.
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