Rotating black holes in a draining bathtub: superradiant scattering of gravity waves

Richartz, Mauricio and Prain, Angus and Liberati, Stefano and Weinfurtner, Silke (2015) Rotating black holes in a draining bathtub: superradiant scattering of gravity waves. Physical Review D, 91 (12). 124018/1-124018/12. ISSN 2470-0029

[img]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1MB) | Preview

Abstract

In a draining rotating fluid flow background, surface perturbations behave as a scalar field on a rotating effective black hole spacetime. We propose a new model for the background flow which takes into account the varying depth of the water. Numerical integration of the associated Klein-Gordon equation using accessible experimental parameters shows that gravity waves in an appropriate frequency range are amplified through the mechanism of superradiance. Our numerical results suggest that the observation of this phenomenon in a common fluid mechanical system is within experimental reach. Unlike the case of wave scattering around Kerr black holes, which depends only on one dimensionless background parameter (the ratio a/M between the specific angular momentum and the mass of the black hole), our system depends on two dimensionless background parameters, namely the normalized angular velocity and surface gravity at the effective black hole horizon.

Item Type: Article
Additional Information: © 2015 American Physical Society
Schools/Departments: University of Nottingham, UK > Faculty of Science > School of Mathematical Sciences
Identification Number: 10.1103/PhysRevD.91.124018
Depositing User: Eprints, Support
Date Deposited: 09 May 2017 08:30
Last Modified: 13 Oct 2017 00:49
URI: http://eprints.nottingham.ac.uk/id/eprint/42624

Actions (Archive Staff Only)

Edit View Edit View