Hawking Radiation from a (4+n)-Dimensional Rotating Black Hole on the Brane

TL;DR

This paper numerically analyzes Hawking radiation from a rotating higher-dimensional black hole on the brane, revealing how angular momentum affects emission rates and super-radiance, extending previous low-energy, low-angular momentum studies.

Contribution

It provides exact numerical results for scalar Hawking radiation from rotating (4+n)-dimensional black holes, including regimes of high energy and angular momentum, and explores super-radiance effects with extra dimensions.

Findings

Hawking radiation emission is suppressed at low energy but enhanced at higher energies with increased angular momentum.

Super-radiance effects are significantly amplified in the presence of extra dimensions.

Results extend previous analytical studies to broader energy and angular momentum regimes.

Abstract

We study the emission of Hawking radiation in the form of scalar fields from a (4+n)-dimensional, rotating black hole on the brane. We perform a numerical analysis to solve both the radial and angular parts of the scalar field equation, and derive exact results for the radial wavefunction and angular eigenvalues, respectively. We then determine the Hawking radiation energy emission rate, and find that, as the angular momentum increases, it is suppressed in the low-energy regime but enhanced in the intermediate and high-energy regimes. Our results agree with previous analytical studies, derived in the low-angular momentum and low-energy approximation, and generalize them to include angular momentum and energy regimes that were until now unexplored. We also investigate the energy amplification due to super-radiance and we find that, in the presence of extra dimensions, the effect is significantly enhanced.