Quantum fluctuations around black hole horizons in Bose-Einstein condensates

TL;DR

This paper investigates how quantum fluctuations and Hawking radiation manifest in Bose-Einstein condensates with acoustic horizons, providing analytical models and confirming non-local correlations as signatures of Hawking radiation.

Contribution

It offers the first detailed analytical description of flow patterns, Hawking radiation spectra, and quantum fluctuations in realistic BEC configurations with acoustic horizons.

Findings

Non-local density correlations serve as clear Hawking radiation signatures.

Analytical models match numerical results for flow and fluctuations.

Short-range density correlations are related to non-local Hawking signals.

Abstract

We study several realistic configurations allowing to realize an acoustic horizon in the flow of a one dimensional Bose-Einstein condensate. In each case we give an analytical description of the flow pattern, of the spectrum of Hawking radiation and of the associated quantum fluctuations. Our calculations confirm that the non local correlations of the density fluctuations previously studied in a simplified model provide a clear signature of Hawking radiation also in realistic configurations. In addition we explain by direct computation how this non local signal relates to short range modifications of the density correlations.