MG11 
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Kaluza-Klein black hole with gravitational charge in Einstein-Gauss-Bonnet gravity

We obtain a new exact black-hole solution in Einstein-Gauss-Bonnet gravity with a cosmological constant which bears a specific relation to the Gauss-Bonnet coupling constant. The spacetime is a product of the usual 4-dimensional manifold with a (n-4)-dimensional space of constant negative curvature, i.e., its topology is locally $M^n \approx M^4 \times H^{n-4}$. The solution has two parameters and asymptotically approximates to the field of a charged black hole in anti-de Sitter spacetime. The most interesting and remarkable feature is that the Gauss-Bonnet term acts like a Maxwell source for large $r$ while at the other end it regularizes the metric and weakens the central singularity.

Final fate of higher-dimensional spherical dust collapse in Einstein-Gauss-Bonnet gravity

We give a model of the higher-dimensional spherical collapse of a dust including the perturbative effects of quantum gravity. The $n (\geq 5)$-dimensional action with the Gauss-Bonnet term for gravity is considered and a simple formulation of the basic equations is given, which is a generalization of the Misner-Sharp formalism in general relativity. There are two families of solutions, which we call plus-branch and the minus-branch solutions. The whole picture and the final fate of the gravitational collapse of a dust differ greatly not only between two branches but also between the cases with $n=5$ and $n \ge 6$. We show that, in the minus branch, which has the general relativistic limit, naked singularities are massless for $n \ge 6$, while massive naked singularities are possible for $n=5$.