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Near-Horizon Metric

  1. Nov 14, 2008 #1
    I am reading this article http://arxiv.org/abs/hep-th/0404008 on general Kerr-de Sitter metrics.
    It seems to be obvious, but I cant see the reason behind the statement that authors make after Equation 4.2 that "As the horizon is approached, the right-hand side of (4.2) approaches zero."
    I would be appreciative if somebody could help me with this issue.
  2. jcsd
  3. Nov 14, 2008 #2
    You might try Wikipedia for a clue,,,
    Kerr Solution or Kerr Neumann Metric..
  4. Nov 15, 2008 #3
    thank you for the tip but if you look at the Boyer-Lindquist form #(4.1), you see that it is quite general and i think their statement is somehow related to the fact that the horizon is a null hypersurface. yet i dont know the 'how' part :)
  5. Nov 15, 2008 #4
  6. Nov 19, 2008 #5
    I must be hanged for not seeing the simple fact that when the metric has the given Lewis form (4.1) if you move to the rotating reference frame, then the near-horizon condition "RHS of Eqn. 4.2 approaches zero" will be obvious.
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