Causal structures and nonlocality in double holography

A bstract Double holography plays a crucial role in recent studies of Hawking radiation and information paradox by relating an intermediate picture, which dynamical gravity living on end-of-the-world brane is coupled to non-gravitational heat bath, much better-understood BCFT picture as well bulk picture. In this paper, causal structures generic double holographic setups are studied. We find that the structure compatible with causality thanks generalization Gao-Wald theorem. On other hand, consistency requires effective theory contain special type super-luminal nonlocal effect significant at long range or IR. These confirmed both geometrical analysis commutators microscopic fields. Subregion correspondences discussed knowledge nonlocality. Possible fundamental origins nonlocality its difference types will also be discussed.