On the effect of scalar fields on Hawking radiation and quasinormal modes of black holes

TL;DR

This paper investigates how a conformally coupled scalar field, acting as 'hair', influences Hawking radiation and quasinormal modes of charged black holes, revealing significant modifications to their physical properties.

Contribution

It introduces a new model of black holes with scalar 'hair' that alters their mass and charge characteristics, impacting their radiation and oscillation modes.

Findings

Scalar 'hair' modifies black hole mass and charge.

Scalar field affects Hawking radiation properties.

Altered quasinormal mode spectra due to scalar hair.

Abstract

The present thesis attempts to study the effect of scalar fields on Hawking radiation and quasinormal modes of black holes. We selected a static, spherically symmetric electrically charged black hole with an additional scalar 'hair' for our analysis. The scalar 'hair' is sourced by a scalar field, conformally coupled to the Einstein-Hilbert action. The scalar field can survive even in the absence of the black hole's electric charge and is characterized as a 'primary hair'. This scalar field changes the gravitational constant, and hence modifies the ADM (Arnowitt-Deser-Missner) mass of the black hole. The scalar field's strength is determined by a scalar 'charge' that manifests itself as an additive correction to the square of the electric charge in the standard Reissner-Nordstr\"{o}m metric. This seemingly simple modification leads to nontrivial physical implications.