# Turbulent Steady States in Two-Dimensional Sonic Black Holes: Superfluid Vortices and Emission of Sound

## TL;DR

This paper investigates the formation of superfluid vortices and sound emission in a 2D Bose-Einstein condensate simulating sonic black holes, revealing turbulent steady states and non-thermal radiation spectra.

## Contribution

It demonstrates the emergence of superfluid turbulence and non-thermal Hawking-like radiation in a 2D sonic black hole simulation, highlighting new dynamical behaviors.

## Key findings

- Superfluid vortices form via dynamical instabilities.
- A quasi-steady turbulent state is reached in the supersonic region.
- Sound emission resembles Hawking radiation but with a non-thermal spectrum.

## Abstract

Simulation of a sonic black-hole/white-hole pair in a (2+1)-dimensional Bose-Einstein condensate shows formation of superfluid vortices through dynamical instabilities seeded by initial quantum noise. The instabilities saturate in a quasi-steady state of superfluid turbulence within the supersonic region, from which sound waves are emitted in qualitative resemblance to Hawking radiance. The power spectrum of the radiation from the slowly decaying two-dimensional sonic black hole is strongly non-thermal, however.