An Information Paradox and Its Resolution in de Sitter Holography

TL;DR

This paper resolves the de Sitter spacetime information paradox by demonstrating the emergence of entanglement islands, leading to a time-dependent Page curve and revealing how microscopic degrees of freedom are distributed across different holographic descriptions.

Contribution

It introduces a resolution to the de Sitter information paradox via entanglement islands within the DS/dS correspondence, applicable in general spacetime dimensions with massless gravitons.

Findings

Entanglement entropy follows a time-dependent Page curve.

Microscopic degrees of freedom are localized near horizons in static descriptions.

In global descriptions, degrees of freedom are distributed uniformly in a semiclassical vacuum.

Abstract

We formulate a version of the information paradox in de Sitter spacetime and show that it is solved by the emergence of entanglement islands in the context of the DS/dS correspondence; in particular, the entanglement entropy of a subregion obeys a time-dependent Page curve. Our construction works in general spacetime dimensions and keeps the graviton massless. We interpret the resulting behavior of the entanglement entropy using double holography. It suggests that the spatial distribution of microscopic degrees of freedom depends on descriptions, as in the case of a black hole. In the static (distant) description of de Sitter (black hole) spacetime, these degrees of freedom represent microstates associated with the Gibbons-Hawking (Bekenstein-Hawking) entropy and are localized toward the horizon. On the other hand, in a global (effective two-sided) description, which is obtained by the quantum analog of analytic continuation and is intrinsically semiclassical, they are distributed uniformly and in a unique semiclassical de Sitter (black hole) vacuum state.