The Gravity Dual of Boundary Causality
Abstract
In gauge/gravity duality, points which are not causally related on the boundary cannot be causally related through the bulk; this is the statement of boundary causality. By the Gao-Wald theorem, the averaged null energy condition in the bulk is sufficient to ensure this property. Here we proceed in the converse direction: we derive a necessary as well as sufficient condition for the preservation of boundary causality under perturbative (quantum or stringy) corrections to the bulk. The condition that we find is a (background-dependent) constraint on the amount by which light cones can "open" over all null bulk geodesics. We show that this constraint is weaker than the averaged null energy condition.
Cite
@article{arxiv.1604.03944,
title = {The Gravity Dual of Boundary Causality},
author = {Netta Engelhardt and Sebastian Fischetti},
journal= {arXiv preprint arXiv:1604.03944},
year = {2016}
}
Comments
14+5 pages, 3 figures. v2: addressed referee comments; amended figures