Thats the question. Even if wormholes exist, the Universe is under no obligation to make them observable to us. If they are always on the other side of a black hole event horizon, then there would be no way for us to detect them, even in principle.

It is true no physical law obligates the universe to make them observable to us. But, this is the same universe that gave rise to Star Trek, Firefly, and especially The Expanse making so many of us dream of interstellar travel. So, I’d say ethically it’s pretty damn obligated to make them observable :)

/s (Sort of.. not really)

This is the same universe that gave rise to the Tide Pod challenge.

Perhaps in the far future there will be a Find a wormhole challenge where future human teenagers will dive their spaceships into a blackhole they think is in fact the entrance to a wormhoe and scream YOLO just before entering the event horizon.

Firefly is all STL. It’s ambiguous how they got to the system they now occupy.

Wait, really? I haven't watched the show, but aren't there like six different habitable planets involved?

You can't have that all in a single star system.

They kinda try to patch it up in the movie "Serenity". Supposedly the whole show takes place in a gigantic star system full of giants with dozens of moons amounting to hundreds of worlds. They also have some form of terraforming tech to make inhospitable worlds habitable.

Frankly I find that whole set up only slightly more plausible than some kind of FTL, especially since they also have gravity manipulation tech already.

More. All geo engineered. Ambiguous how humanity got to the system though.

That said recent talks about habitable zone around a black hole made me wonder if that would work.

IIRC it's spelled out somewhere that the colonization fleet was generation ships.

I honestly did not remember that.

Good point.

Life imitates art, the universe will surely give :)

If they are undetectable, that is, never ever influence anything in the observable universe, the Occam razor instantly shaves them off.

Would we not be able to infer their existence by finding a white hole? I do see how calling that a detection could be a stretch.

Actually, GR describes white holes, along with black holes, but no ideas how a white hole would form in the real universe apparently exist.

If they're not observable then they're all unidirectional from here to somewhere over there (or from there to here but there is nothing over there, not even vacuum fluctuations).