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Approach to the extremal limit of the Schwarzschild-de Sitter black hole

Alec Maassen van den Brink
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Abstract

The quasinormal-mode spectrum of the Schwarzschild-de Sitter black hole is studied in the limit of near-equal black-hole and cosmological radii. It is found that the mode_frequencies_ agree with the P"oschl-Teller approximation to one more order than previously realized, even though the effective_potential_ does not. Whether the spectrum approaches the limiting one uniformly in the mode index is seen to depend on the chosen units (to the order investigated). A perturbation framework is set up, in which these issues can be studied to higher order in future.

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Alec Maassen van den Brink. 2003-05-02. Approach to the extremal limit of the Schwarzschild-de Sitter black hole. https://doi.org/10.1103/physrevd.68.047501

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