Scalar fields in the Lense-Thirring background with a cosmic string and Hawking radiation

TL;DR

This paper studies how a cosmic string and a rotating black hole affect a massive scalar field, providing exact solutions and exploring implications for Hawking radiation.

Contribution

It derives exact solutions of the Klein-Gordon equation in a Lense-Thirring black hole spacetime with a cosmic string, highlighting the string's influence.

Findings

Exact solutions in terms of confluent Heun functions

Analysis of scalar field behavior near the horizon

Discussion of Hawking radiation of massive particles

Abstract

We analyze the influence of the gravitational field produced by a slowly rotating black hole with a cosmic string along the axis of symmetry on a massive scalar field. Exact solutions of both angular and radial parts of the Klein-Gordon equation in this spacetime are obtained, and are given in terms of the confluent Heun functions. We emphasize the role of the presence of the cosmic string in these solutions. We also investigate the solutions in regions near and far from the event horizon. From the radial solution, we obtain the exact wave solutions near the exterior horizon of the black hole, and discuss the Hawking radiation of massive scalar particles.