Perturbations of Schwarzschild black holes in laboratories

TL;DR

This paper establishes a precise laboratory analog between acoustic waves in a Laval nozzle and perturbations of Schwarzschild black holes, enabling experimental observation of black hole-like phenomena such as quasinormal modes.

Contribution

It derives the exact shape of a Laval nozzle that replicates Schwarzschild black hole perturbations, creating a new experimental platform for black hole physics.

Findings

Exact Laval nozzle form matching black hole wave equations

Laboratory observation of black hole quasinormal oscillations

Simulation of wave scattering and tunneling phenomena

Abstract

It is well-known that the perturbations of Schwarzschild black holes are governed by a wave equation with some effective potential. We consider perturbations of a gas in a tube called Laval nozzle, which is narrow in the middle and has a sonic point in the throat. By equating the wave equation in a Laval nozzle of an arbitrary form with the wave equation of spin-s perturbations of Schwarzschild black holes, we find the exact expression for the form of the Laval nozzle, for which acoustic perturbations of the gas flow corresponds to the general form of perturbations of Schwarzschild black holes. This allows observation, in a laboratory, of the acoustic waves, which are analogue of damping quasinormal oscillations of Schwarzschild black holes. The found exact acoustic analog allows to observe also some other phenomena governed by the wave equation, such as the wave scattering and tunneling.