Different faces of the phantom

TL;DR

This paper explores the implications of phantom matter in the universe, showing how its perturbations can prevent future singularities and lead to stable structures like black holes within an expanding universe.

Contribution

It demonstrates that under certain conditions, phantom matter perturbations can avoid the Big Rip and form stable black hole configurations.

Findings

Perturbations of phantom matter can prevent future singularities.

Local concentrations of phantom matter can form black holes.

Stable, singularity-free universe models with black holes are possible.

Abstract

The SNe type Ia data admit that the Universe today may be dominated by some exotic matter with negative pressure violating all energy conditions. Such exotic matter is called {\it phantom matter} due to the anomalies connected with violation of the energy conditions. If a phantom matter dominates the matter content of the universe, it can develop a singularity in a finite future proper time. Here we show that, under certain conditions, the evolution of perturbations of this matter may lead to avoidance of this future singularity (the Big Rip). At the same time, we show that local concentrations of a phantom field may form, among other regular configurations, black holes with asymptotically flat static regions, separated by an event horizon from an expanding, singularity-free, asymptotically de Sitter universe.