Perturbations of massless external fields in Horndeski hairy black hole

TL;DR

This study investigates how massless external fields behave around Horndeski hairy black holes, analyzing stability, quasinormal modes, and Hawking radiation, revealing the influence of Horndeski hair on black hole properties.

Contribution

It provides a comprehensive analysis of external field perturbations in Horndeski hairy black holes using both numerical and analytical methods, highlighting the effects of Horndeski hair.

Findings

Black holes are stable under these perturbations.

Horndeski hair affects energy emission rates.

Horizon hair can extend or shorten black hole lifetime.

Abstract

In this paper, we study the propagations of external fields in Horndeski theory, including the scalar field, electromagnetic field and Dirac field. We extensively explore the quasinormal frequencies, time evolution, greybody factors and emission rates of those massless perturbing fields by solving the corresponding master equations in the Horndeski hairy black hole. With the use of both numerical and analytical methods, we disclose the competitive/promotional influences of the Horndeski hair, spin and quantum momentum number of the external fields on those phenomenal physics. Our results show that the Horndeski hairy black hole is stable under those perturbations. Moreover, a larger Horndeski hair could enhance the intensity of energy emission rate for Hawking radiation of various particles, indicating that comparing to the Schwarzschild black hole, the Horndeski hariy black hole could have longer or shorter lifetime depending on the sign of the Horndeski hair.