My experience with solitons is restricted to the classical setting, namely solutions to the quartic interaction $\phi^4$, the Sine-Gordon equation, and Korteweg–de Vries equations. I was explicit to show the boundary on my solitonic knowledge so that I could ask for an interpretation of the recent paper
In particular I do not understand the difference between solitons and vortex rings. My confusion stems from the introduction to the video Baths and Quarks.
In the intro David Tong is blowing toroidal shaped bubbles, which I thought were examples of solitons. A phenomena which dolphins exhibit for play. However, in the watered down discussion of the aforementioned paper the nomenclature vortex ring is used. Moreover, the so called "heavy soliton" posited in the Fermi gas is shown to be a quantized vortex ring. My guess is that the difference in word usage stems from the language of superfluid density functional theory. However my lack of expertise in the subject allows me to not go further than guessing at this stage.
Could someone explain the difference, if there exists any, between the usage of the words soliton and vortex ring?