Detecting rotational superradiance in fluid laboratories

Cardoso, Vitor and Coutant, Antonin and Richartz, Mauricio and Weinfurtner, Silke (2016) Detecting rotational superradiance in fluid laboratories. Physical Review Letters, 117 (27). 271101/1-271101/6. ISSN 1079-7114

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Abstract

Rotational superradiance was predicted theoretically decades ago, and is chiefly responsible for a number of important effects and phenomenology in black-hole physics. However, rotational superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behavior of sound and surface waves in fluids resting in a circular basin at the center of which a rotating cylinder is placed. We show that with a suitable choice for the material of the cylinder, surface and sound waves are amplified. Two types of instabilities are studied: one sets in whenever superradiant modes are confined near the rotating cylinder and the other, which does not rely on confinement, corresponds to a local excitation of the cylinder. Our findings are experimentally testable in existing fluid laboratories and, hence, offer experimental exploration and comparison of dynamical instabilities arising from rapidly rotating boundary layers in astrophysical as well as in fluid dynamical systems.

Item Type: Article
Schools/Departments: University of Nottingham, UK > Faculty of Science > School of Mathematical Sciences
Identification Number: 10.1103/PhysRevLett.117.271101
Depositing User: Eprints, Support
Date Deposited: 27 Feb 2017 09:45
Last Modified: 13 Oct 2017 01:41
URI: http://eprints.nottingham.ac.uk/id/eprint/40855

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