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Gravitational non linearity: the glue of Black Holes

  1. Apr 13, 2013 #1
    Any comments on the following description from Kip Thorne, BLACK HOLES AND TIME WARPS, 1994, Box 10.1 would be appreciated. It seems odd to me that at some given curvature, gravity would become self sustaining...if that is what he is saying.

    We have previously discussed in these forums that the current causal event horizon is affected by any future growth of the black hole.... and the causal event horizon grows in anticipation or a BH merger or in-falling mass-energy. Can those effects be reconciled with the above description or do you think Thorne's 'quiescent' discussion is too simple to account for any accretion?? [that's my take]
  2. jcsd
  3. Apr 13, 2013 #2


    Staff: Mentor

    It is. But note that it's not "at some given curvature", because the curvature at the hole's horizon varies inversely with its mass. For a large enough hole, curvature at the horizon is negligible, so the formation of a horizon, which I think is basically what Thorne means by "the hole holding itself together", can't be a function of curvature.

    Sure. Any time additional matter falls into the hole, it works similarly to the collapse of the matter that intially formed the hole. Once the matter falls through the horizon, it can't hold the hole together at its new, larger mass. So the hole holding together at its new, larger mass must be due to GNL, just as the hole holding together at its original, smaller mass was. It's the same thing.
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