The superradiant instability spectrum of the hydrodynamic vortex model

Shahar Hod

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arXiv · 2312.13354

The superradiant instability spectrum of the hydrodynamic vortex model

Shahar Hod

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Abstract

We study analytically the superradiant instability properties of the hydrodynamic vortex model, an asymptotically flat acoustic geometry which, like the spinning Kerr black-hole spacetime, possesses an effective ergoregion. In particular, we derive a compact analytical formula for the complex resonant frequencies that characterize the long-wavelength dynamics of sound modes in this physically interesting acoustic spacetime.

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Shahar Hod. 2023-12-20. The superradiant instability spectrum of the hydrodynamic vortex model. https://arxiv.org/abs/2312.13354

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