Weakly trapped surfaces in asymptotically de Sitter spacetimes

TL;DR

This paper explores the visibility of trapped surfaces in asymptotically de Sitter spacetimes, revealing conditions under which such surfaces can be visible from infinity, unlike in non-positive cosmological constant cases.

Contribution

It demonstrates the existence of visible marginally trapped surfaces in de Sitter spacetimes and establishes conditions for their non-visibility.

Findings

Visible marginally trapped surfaces can exist in de Sitter spacetimes.

Natural conditions for non-visibility of trapped surfaces are identified.

The behavior differs significantly from the non-positive cosmological constant case.

Abstract

It is a standard fact that trapped or marginally trapped surfaces are not visible from conformal infinity, under the usual set of conditions on matter fields and the conformal completion, provided that the cosmological constant is non-positive. In this note we show that the situation is more delicate in the presence of a positive cosmological constant: we present examples of visible marginally trapped surfaces, and we provide a set of natural conditions which guarantee non-visibility.