Quasinormal modes of black holes absorbing dark energy

TL;DR

This paper investigates how black hole perturbations are affected by absorbing different forms of dark energy, revealing potential observational signatures and instabilities linked to the nature of dark energy.

Contribution

It introduces a detailed analysis of black hole perturbations under dark energy accretion, highlighting distinct behaviors for different dark energy models and connecting to the Big Rip scenario.

Findings

Phantom energy accretion causes growing perturbation modes.

Perturbation behaviors differ between dark energy types.

Instability aligns with the Big Rip fate of the universe.

Abstract

We study perturbations of black holes absorbing dark energy. Due to the accretion of dark energy, the black hole mass changes. We observe distinct perturbation behaviors for absorption of different forms of dark energy into the black holes. This provides the possibility of extracting information whether dark energy lies above or below the cosmological constant boundary $w=-1$. In particular, we find in the late time tail analysis that, differently from the other dark energy models, the accretion of phantom energy exhibits a growing mode in the perturbation tail. The instability behavior found in this work is consistent with the Big Rip scenario, in which all of the bound objects are torn apart with the presence of the phantom dark energy.