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The attraction of light by gravity

  1. Aug 10, 2005 #1
    Could you please give me some brief explanation of the attraction of light by gravity. Or maybe some links where I can read something about it. :)

    Thank you!
  2. jcsd
  3. Aug 10, 2005 #2


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    Gold Member

    Very briefly, light follows the geodesic paths that Einstein proposed rather than actual 'straight' lines. Where spacetime is distorted by a gravitational field, the photons follow the 'surface'... sort of like a race car on a banked curve.
  4. Aug 10, 2005 #3
    PBS has a program called Nova: The Elegant Universe that you can watch over the internet that tells about light following the dips in space as if it were a blanket. It's been over a year since I watched them so I don't remember which episode explains what your looking for. But I know they're all worth your time to watch, as theyre very interesting, and one of them does have a lot of useful information about light and gravity.
  5. Aug 17, 2005 #4
    The Effect of Gravity on Light

    I once read that light is slowed down by a gravitational field.
    Later, I read that spacetime contorts and c remains the same.
    Which is true?

  6. Aug 17, 2005 #5


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    close...the speed of light doesnt change but its is redshifted, for example, lets say light was escaping the gravitational field of a large star, the light would have to do work to escape it (its force of gravity) so it would use up some of its energy, therefore lowering the frequency. so having the frequency lowered the colour you observer will be more to the left side of the em spectrum then it actually is.
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