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

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 equa...

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Main Authors: Richartz, Mauricio, Prain, Angus, Liberati, Stefano, Weinfurtner, Silke
Format: Article
Published: American Physical Society 2015
Online Access:https://eprints.nottingham.ac.uk/42624/
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author Richartz, Mauricio
Prain, Angus
Liberati, Stefano
Weinfurtner, Silke
author_facet Richartz, Mauricio
Prain, Angus
Liberati, Stefano
Weinfurtner, Silke
author_sort Richartz, Mauricio
building Nottingham Research Data Repository
collection Online Access
description 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.
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spelling nottingham-426242020-05-04T17:11:21Z https://eprints.nottingham.ac.uk/42624/ Rotating black holes in a draining bathtub: superradiant scattering of gravity waves Richartz, Mauricio Prain, Angus Liberati, Stefano Weinfurtner, Silke 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. American Physical Society 2015-06-05 Article PeerReviewed Richartz, Mauricio, Prain, Angus, 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 https://doi.org/10.1103/PhysRevD.91.124018 doi:10.1103/PhysRevD.91.124018 doi:10.1103/PhysRevD.91.124018
spellingShingle Richartz, Mauricio
Prain, Angus
Liberati, Stefano
Weinfurtner, Silke
Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title_full Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title_fullStr Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title_full_unstemmed Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title_short Rotating black holes in a draining bathtub: superradiant scattering of gravity waves
title_sort rotating black holes in a draining bathtub: superradiant scattering of gravity waves
url https://eprints.nottingham.ac.uk/42624/
https://eprints.nottingham.ac.uk/42624/
https://eprints.nottingham.ac.uk/42624/