[krapp]

>Obviously, for the extraterrestrial theory to work, you have to imagine you can warp or fold spacetime to get where you need to go, rather than using a conventional engine.

That's fantasy, though. One might as well imagine aliens coming to Earth riding dragons through magic portals, as far as reality is concerned.

For any extraterrestrial theory to work and be plausible as a speculative explanation for real world events, it has to assume the speed of light is an inescapable hard limit on everything, because that seems to be the universe we actually live in.

[klingonopera]

Wormholes can exist on hard and solid physics theories, and people are trying to find out if they can make this work in practical situations.

Therefore, your "fantasy" of them coming to earth through magic portals may not be so far off. Whether or not a dragon makes for a good spaceship remains to be seen...

[krapp]

> Wormholes can exist on hard and solid physics theories, and people are trying to find out if they can make this work in practical situations.

You kind of skipped over the part where someone discovers that wormholes do actually exist, and that it's possible for anything to traverse them, much less circumvent the speed of light while doing so. There is, as yet, not "this" to make work in any practical situation. Theories abound, but not all of them agree that wormholes, if they were to exist, are even practical[0].

[0]https://news.ycombinator.com/item?id=19665563