Charged Regular Black Holes From Quasi-topological Gravities in $D\ge 5$

Abstract

The investigation of gravity in higher-dimensional spacetime has transitioned from a mathematical curiosity to a fundamental framework in theoretical physics, catalyzed by the dimensional requirements of String theory and M-theory. In this paper, we explicitly construct a spherically symmetric charged black hole solution in $D \ge 5$ dimensions within a gravity theory featuring an infinite tower of higher-curvature corrections. For a given mass and electric charge, the model admits a unique static spherically symmetric solution. We demonstrate that, with an appropriate choice of coupling coefficients $\alpha_n$, the central singularity is progressively mitigated as the correction order increases, ultimately resolving into a globally regular spacetime in the limit of infinite-order corrections. Furthermore, the criteria for the existence of extremal black holes are determined.