I'm assuming that each "vortex" is unique. So for a collection of n vortices, given constraints (probably botching the jargon, I'm a recovering XQuery guy bear

I'm assuming that each "vortex" is unique. So for a collection of n vortices, given constraints (probably botching the jargon, I'm a recovering XQuery guy bear with me) of sets of k size, how do you prove a subset of t is always unique throughout the collection. And I guess the proof they proffer extends to infinity? A perspective given in the article was sort of, if there's no evidence to the contrary, it's probably true, but my take-away is these 3 folks proved it? I'm sure I could read the papers, though I doubt I'd understand them. But it seems so straightforward. It's combinatorical, so gets out of hand easily I'm sure, but what am I missing here? Loved the write-up though. The carpet example made me giggle.