# The zero mass limit of Kerr and Kerr-(anti-)de Sitter space-times: Revisited

## TL;DR

This paper revisits the zero mass limit of Kerr and Kerr-(anti-)de Sitter space-times, analyzing wave equations, reflection coefficients, and Hawking radiation, finding no evidence of Hawking radiation in de Sitter geometry.

## Contribution

It investigates the zero mass limit of Kerr-(anti-)de Sitter space-times, focusing on wave solutions, reflection coefficients, and Hawking radiation, providing new insights into their properties.

## Key findings

- No Hawking radiation detected in de Sitter geometry
- Polynomial solutions for radial wave equations identified at special frequencies
- Reflection coefficients computed for waves near horizons

## Abstract

We continue studying the zero mass limit of the Kerr- (Anti) de Sitter space-times by investigating the possibility of special values of the frequencies to have polynomial solutions for the radial wave equation, compute reflection coefficient for waves coming from and going to the cosmological horizon and see whether there is Hawking radiation for de Sitter geometry. We used the Parikh-Wilczek method to study this property and could not find Hawking radiation.