Princeton University Gravity Initiative Seminar Series

Abstract: The quantum extremal surface (QES) formula is an important tool for computing entropy in gravity. For a while, the lore was that this formula offers a good approximation whenever the state is sufficiently semiclassical, i.e. well-described by quantum fields on a curved background. This talk will discuss two papers: in the first [https://arxiv.org/abs/2008.03319], we demonstrate that this lore is incorrect and offer a simple replacement. In the second [https://arxiv.org/abs/2307.13032], we generalize our replacement to arbitrary spacetimes.