Page curve and island in EGB gravity

Abstract

In this paper, the information paradox on lower-dimensional Gauss–Bonnet gravity, known as a three-dimensional EGB black hole, is studied using the quantum extremal island approach. For that, we connect an auxiliary flat bath system to this timelike singularity spacetime and estimate the entropy of hawking radiation in its asymptotic regions when gravity is weak. The addition of island areas to the entanglement wedge of radiation causes its entropy to obey the Page curve, as shown. The quantum extremal surface, or island boundary, is outside the horizon. This yields a time-independent equation for Hawking radiation fine-grained entropy compatible with the appropriate Page curve. We also discover the modifications to this entropy and Page time.