Sadly, I've come to believe that any story with FTL in it must be classified as fantasy. I might be willing to accept natural wormhole travel. Even with generation ships, authors vastly underestimate the difficulties of traveling interstellar distances. When authors posit intergalactic travel, forget about it! Galaxies might as well be pocket universes because they don't interact. (Unless they collide, which will happen with the Milky Way and Andromeda in about 4.5 billion years. Oh man if we can make it that long and have even slow interstellar travel, what an opportunity for exploration!)
But yeah, thank god most of science fiction is actually fantasy because if any of those things were possible, they'd immediately be used to destroy planets. Ships going FTL could be collided into a planet. Teleportation and easily accessed anti-matter could be used to annihilate cities - or planets. Most authors don't even bother building in reasons why that can't happen, its just that no-one thinks of doing it.
I think the limits of the real world are quite fascinating. It's almost like reality was designed to support a huge array of civilizations that cannot interfere with each other. Interstellar travel is so hard that any civ capable of it is going to be capable of executing technologically advanced projects over centuries or millenia, and I daresay such a civ is not doing it for conquest, but to discover and explore. If the urge is militaristic, then such a civ would turn on itself long before the project succeeds. There's a kind of poetry to it.
But yeah, thank god most of science fiction is actually fantasy because if any of those things were possible, they'd immediately be used to destroy planets. Ships going FTL could be collided into a planet. Teleportation and easily accessed anti-matter could be used to annihilate cities - or planets. Most authors don't even bother building in reasons why that can't happen, its just that no-one thinks of doing it.
I think the limits of the real world are quite fascinating. It's almost like reality was designed to support a huge array of civilizations that cannot interfere with each other. Interstellar travel is so hard that any civ capable of it is going to be capable of executing technologically advanced projects over centuries or millenia, and I daresay such a civ is not doing it for conquest, but to discover and explore. If the urge is militaristic, then such a civ would turn on itself long before the project succeeds. There's a kind of poetry to it.