This can be anything from Hyperspace in Star Wars, Warp Drive in Star Trek, travel through the Warp in Warhammer 40k or anything else.
I’ve always liked “slow” FTL travel, where going a few light-years still takes a few days or so. I also really like travel through an alternate dimension like in 40k, Event Horizon, Witchspace in Elite Dangerous.
I wanna know your favorite versions, or do you prefer stories that obey the laws of known physics, like the Expanse or Rimworld?
Singularity Sky by Charles Stross. It deals heavily with causality and “light cones.” There’s some super advanced entity in the universe that enforces a ban on causality-breaking FTL, so it’s not possible for anything to mess with the entity’s development, iirc.
Stross’s Neptune Brood also has some interesting stuff about FTL economics. It’s somewhat of a satire on cryptocurrency, NFTs, and marketization in general.
I wouldn’t call it a satire; it’s more a thought exercise on how to make galactic colonization economically viable. The cost involved in setting up a colony that’s tens or hundreds of light years away would be astronomical, and the return on investment would take so long that it’s simply not reasonable under any current economic system. Right now we talk about how it would be hard to colonize Mars, and that’s only about nine months of travel, and not at anything close to relativistic speeds.
Yeah, some of it felt a little tongue in cheek though. Like people having their own reputation markets where everyone could buy/sell shares on others reputation.
So is there no FTL, or just some kind of heavy restriction on FTL? Any FTL will break causality in some frame of reference, using real world physics.
Here’s how I remember it, could be wrong, been a long time. The super advanced entity, the Eschaton, descends from humans in the future. Any FTL travel that would break causality within the Eschaton’s historical light cone is banned; I.e. anything that could interfere with the Eschaton’s development. Human civilizations have causality-safe jump drives that navigate in ways that avoid causality violations within the Eschaton’s historical light cone.
Ah, okay, I get it! That’s pretty cool.
So then could/did characters onboard FTL vessels engage in time travel shenanigans, as long as it was all resolved by the time they slowed back down? (If you can remember)