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The Schwarzschild radius for 11D BHs is given by $l_{11}(l_{11}m)^{1/8}$, which is the special case ($D=11$) of the general dimensional case of $(G_Dm)^{\frac{1}{D-3}}$. Here $m$ is the BH mass and $G_D$ is $D$ dimensional Newton's constant. Now if M-theory is compactified on a torus $T^p$ of sizes $L$s, then I think $G_D$ is related to eleven dimensional Planck length $l_{11}$ as $G_D=\frac{l_{11}^9}{L^p}$. I don't understand how can then the radius smoothly go to the 11 dimensional value if we start decompactifying the torus to get to the 11D case. It seems that it blows up. Where's my mistake? Thanks a lot.

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