Unruh-DeWitt detectors and entanglement: the anti-de Sitter space

TL;DR

This paper studies how entanglement can be harvested by particle detectors in AdS4 space, revealing effects of boundary conditions, detector motion, and spacetime size on entanglement behavior.

Contribution

It extends entanglement harvesting analysis to AdS4, exploring effects of boundary conditions, detector configurations, and revealing novel features like separability islands.

Findings

At large AdS length, results approximate flat space.

Boundary conditions significantly affect entanglement harvesting.

Identified a separability island in parameter space.

Abstract

We investigate entanglement harvesting in AdS$_4$. Applying the general results of [Phys. Rev. D 97, 125011 (2018)], we consider two scenarios: one where two particle detectors are geodesic, with equal redshift; and one where both are static, at unequal redshift. As expected, at large AdS length $L$, our results approximate flat space. However at smaller $L$ we observe non-trivial effects for various field boundary conditions. Furthermore, in the static case we observe a novel feature of the entanglement as a function of switching time delay, which we attribute to different (coordinate) frequencies of the detectors. We also find an island of separability in parameter space, analogous that that observed in AdS$_3$, to which we compare and contrast our other results. The variety of features observed in both cases suggest further study in other spacetimes.