Black Hole Entropy: Is S=A/4 robust ?

Pacopag
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I would like to use the formula S=A/4 to find the entropy of a black hole. But before I go ahead and believe that formula, there are a couple of subtleties that are troubling me.

First of all, in just about every "classical" treatment of black hole thermodynamics, there is usually the underlying assumption that the spacetime is 4-dimensional, and asymptotically flat. Does anyone know if the above formula S=A/4 holds in higher-dimensional spacetimes that aren't asymptotically flat?

Thanks.
 
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S=A/4 is valid in higher dimensions. I am not sure about asymptotic flatness.
 

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