Page curves on codim-m and charged branes

Abstract

This paper investigates Page curves on the branes with higher codimensions and charges. We study two kinds of doubly holographic modes, the AdS/dCFT and cone holography. In AdS/dCFT, the gravitations on the brane are massive, and the black hole on the codim-m brane is coupled with the non-gravitational bath on the AdS boundary. Following the standard approach, we derive the Page curve for eternal black holes. On the other hand, cone holography includes massless graviton on the brane, and the bath becomes gravitating. By adding suitable DGP gravity on the end-of-the-world brane, we recover non-trivial entanglement islands and Page curves, which strongly support that the island is consistent with massless gravity. Finally, we analyze the effects of charges and find that, as the charges increase, the Page time increases, and the parameter space for non-trivial Page curves widens.