Comment on "Quantum entangled dark solitons formed by ultracold atoms in optical lattices"

TL;DR

This paper highlights that two-body correlation functions alone cannot determine the presence or absence of solitons in individual experimental runs, emphasizing the need for more detailed analysis.

Contribution

It demonstrates that g2 correlation functions are insufficient to infer soliton filling in experiments, challenging common assumptions in quantum soliton analysis.

Findings

g2 correlation functions can be filled in while solitons are not present

Two-body correlations do not reliably indicate soliton presence

Highlights limitations of using g2 for soliton detection

Abstract

We demonstrate that knowledge of two body correlation functions like g2(x) is insufficient to draw conclusions about whether solitons fill in or not in individual experimental runs. In our example, g2 is filled in, while the soliton is not.