Charged black holes in higher-dimensional Eddington-inspired Born-Infeld gravity

Abstract: We study static (electrically)-charged solutions of Eddington-inspired Born-Infeld (EiBI) theory of gravity in general $D$-dimensional spacetime. We consider both linear (Maxwell) as well as nonlinear electrodynamics for the matter fields. In this particular work, the nonlinear theory we specifically consider is the Born-Infeld electrodynamics. The solutions describe higher-dimensional black holes in EiBI gravity. For the linear Maxwell field, we show that the electric field is still singular for $D>4$. This singularity is cured when EiBI is coupled to the BI electrodynamics. We obtain EiBI-BI black hole solutions in the limit of ${\tilde\alpha}\equiv4\kappa b^2/\lambda=1$ and $2$. We also investigate their thermodynamical property. It is found that $\kappa$ imposes a charge screening that makes the corresponding Hawking temperature experiences some sudden jump from charged-type to the Schwarzschild-type at some critical value of $\kappa$. Thermodynamical stability reveals that the EiBI-BI black holes can exist with smaller horizon than the RN.