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Absolute Rest & Black Holes

  1. Jan 26, 2010 #1

    If time stops at the event horizon of a black hole..which means there is no motion happening or can be observed..does that not mean that the centre of a black hole is a place of absolute rest?

    Could such a place of ab/rest 'move' thru the cosmos (basically a black hole which is a dead star) from its place of birth?

    I would think that the centre of black holes would fill the role of the 'Either'...where both objects and light would have a relative speed with respect to a place of ab/rest?

    Why can a light wave not leave the region of a black hole?

    Thank you for any and all responses..it will help me to pin down certain ideas I have.
  2. jcsd
  3. Jan 26, 2010 #2
    Use the escape velocity formula with v=c to get the schwarzschild radius.
    If you calculate the http://en.wikipedia.org/wiki/Gravitational_redshift" [Broken] for light moving normally away, you get z→∞ as r→rs+, so for r=rs it is physically dead
    Last edited by a moderator: May 4, 2017
  4. Jan 26, 2010 #3
    It is oversimplified popular explanation.
    Yes, light from horizon gets infinitely redshifted.
    But for the falling observer nothing happens when he crosses the event horizon.
    For the free falling observer metrics is normal (locally) all the way to singularity
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