Late-time Evolution of a Charged Massless Scalar Field in the Spacetime of a Dilaton Black Hole

TL;DR

This paper studies how charged massless scalar fields decay over time around dilaton black holes, revealing slower decay for charged fields and implications for black hole internal structure.

Contribution

It provides analytical and numerical analysis of late-time decay of charged scalar fields in dilaton black hole spacetimes, highlighting differences from neutral fields.

Findings

Charged fields decay slower than neutral ones.

Inverse power-law decay observed at all relevant regions.

Oscillatory decay along the horizon impacts mass inflation scenarios.

Abstract

We investigate the power-law tails in the evolution of a charged massless scalar field around a fixed background of a dilaton black hole. Using both analytical and numerical methods we find the inverse power-law relaxation of charged fields at future timelike infinity, future null infinity, and along the outer horizon of the considered black hole. We invisage that a charged hair decays slower than neutral ones. The oscillatory inverse power law along the outer horizon of the dilaton black hole is of a great importance for a mass inflation scenario along the Cauchy horizon of a dynamically formed dilaton black hole.