Slowly rotating black holes in Einsteinian cubic gravity
Connor Adair, Pablo Bueno, Pablo A. Cano, Robie A. Hennigar, Robert B. Mann
Abstract
We construct slowly rotating black-hole solutions of Einsteinian cubic gravity (ECG) in four dimensions with flat and anti--de Sitter asymptotes. At leading order in the rotation parameter, the only modification with respect to the static case is the appearance of a nonvanishing ${g}_{t\ensuremath{\phi}}$ component. Similar to the static case, the order of the equation determining this component can be reduced twice, giving rise to a second-order differential equation, which can be easily solved numerically as a function of ECG coupling. We study how various physical properties of the solutions are modified with respect to the Einstein gravity, including its angular velocity, photon sphere, photon rings, shadow, and innermost stable circular orbits (in the case of timelike geodesics).