Year: 2024
Type: article
Abstract: In this paper, we study rotating horizonless black shells as an alternative to Kerr black holes. We make use of Ernst’s potential to solve the Einstein equations perturbatively in the angular momentum a . Calculating to order a 6 , we find accurate predictions up to about a = 0.45 , where the quadrupole moment is predicted to be around 1% higher than its Kerr value; higher multipole moments show deviation of the order of ∼ 10 % . Our analysis takes into account deformations of the black shells, and we propose that it can be used for numerical simulations comparing gravitational waves emitted by orbiting black shells with those emitted by orbiting black holes. We find that matter on the rotating shell takes the form of a viscous fluid. We make extensive use of relativistic hydrodynamics, and discover an intricate structure of circulating flows of this fluid and heat on the black shell, sustained by the Unruh effect. Published by the American Physical Society 2024
Authors: Ulf Danielsson, Suvendu Giri
Institutions: Uppsala University, Princeton University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Funder: Vetenskapsrådet
OpenAlex ID: W4391162850