We would totally get into a sunk cost fallacy war with any alien races we were to discover. Not to mention unless it's true FTL that one second in there is at most one second outside of it it'll result still in essentially generational ships to reach distant stars.
this post was submitted on 25 May 2026
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You could almost say, a Forever War
You know techbros would try to integrate it into everyone's terrestrial life and unprecedented nightmares would ensue, like light-speed schoolbusses torpedoing into hospitals wiping out all life in a 10-mile radius
There's much more to colonizing a planet than just traveling there. It's a massive ugly investment that may never turn a profit.
For example we have technology allowing travel to the moon, but that doesn't mean we're going to colonize it any time soon.
Colonizing other continents was also both hella dangerous and expensive at the time.
I think there's a lot of factors, including where the FTL transit time, potentia habitability of the destination, and conditions back on Earth.
There's a big difference between "hey we're sending you lot on a trip with at least a year transit time to a potentially hostile destination" versus "go ahead and start building, if you need anything call Tony and he'll have a guy there by Tuesday".
If FTL were a thing, or even near FTL with long-term habitability I don't totally see something like the Mormon Ark-Ship (from the Expanse) being funded by a wealthy enough group.
They are talking about setting up moon colonies soon though, that's what the artimis missions are building up to. Afaik China is doing the same thing.
They are talking about setting up moon colonies soon though
Bases, not colonies. Colony implies you can start family there. That won't be the case for a long time
The first people to invent FTL travel will have always been the undisputed rulers of all mankind, with no challenges to their authority ever observed by anyone.
No, not unless it is some sort of instantaneous matter transmission. Assuming mass and inertia still apply it would still take years to get to the closes suns. Hugh expense, difficult to control and limited benefit. Probably end up bankrupting the sending country.
I think you are missing the joke that they would be time traveling as well as space traveling, and could return before they left. With that capability, they could deliver future weaponry and resources to their former selves.
A bit technical but still readable. There's fundamentally no way to travel faster than light that couldn't be used to send information back in time.
The message literally crosses the path of the ship. It can observe it there. Causality is not violated.
Wormholes don't fit into that idea. I would consider that to be FTL even though your actual speed doesn't need to be all that fast to make use of them.
I think they do. The logic holds as long as there is a method of faster than light communication, regardless of whether that method involves objects actually traveling faster than light or objects traveling through a wormhole.
Actually there is. The issue with that proof is that is assumes that local arrow of time for the thing you're sending back goes forward. This is just an assumption. There's no proof that it does.
In other words: If your local time goes backward as you travel back in time, there's no paradox since paradox causing information will just unwrite itself from your brain as you get younger.
There are so many good literary possibilities with this. Imagine a ship of older such types sent to a distant planet. They not only start de-aging during the journey but also losing memories to the point where a bunch of very confused young people arrives at a distant planet where their most recent memory is fighting with mom & dad over being able to drive the car and no idea how/why they're on a habitable but distant planet
Should plan it so that they were recently trained and briefed on their mission on that new planet, so instead of being just after they’ve argued with their parents they have just finished their training
Maybe it'd be like military service, except they sign up at 18, get shipped out at 70, and arrive... at 18
If FTL was ever invented, we'd have paradoxes where effects happen before their cause, so literally anything is possible.
You could jump forward and observe yourself, but you're not actually there anymore. It's kind of like shouting in to a long tube.
What kind of paradox would you see happening? (pun intended)
https://en.wikipedia.org/wiki/Tachyonic_antitelephone
Basically, an "instant" communication device can create paradoxes.
E.g.
Earth sends mars a instant message. Mars the relay's it via normal radio to a passing ship/probe moving at 0.99C. That probe then sends an "Instant" message to Earth.
The final message will (depending on alignments etc) arrive before the original was sent. If the message the voids the reason for the original message to be sent then a paradox happens.
You can make similar things happen with any form of FTL communication. C isn't technically the speed of light, it is the speed of information. It just happens that light has no other speed limiting, and so moves at maximum speed.
The reason why there will be paradoxes (where an observer can see a message and send a reply that arrives back to the sender before they sent the message) is explained basically everywhere FTL is discussed.
The explanation isn't trivial enough for a comment field, so have a link:
https://www.youtube.com/watch?v=an0M-wcHw5A
Anytime you move at a different speed, the definition of what time matches your current time shifts throughout the universe by an interval proportional to the distance—even if you’re just driving down the street, the time that matches “now” in your reference frame in a distant galaxy could change by years relative to what it was when you were stationary. Of course, you can’t actually see that happening, so the difference is just theoretical... as long as you can’t teleport to that galaxy faster than light.
But as soon as you have any kind of FTL travel, it’s trivially easy to go back in time by warping back and forth between two moving endpoints.
That is not how speed works in relativity. Even moving with 10 times the speed of light, you still take "forward time" to move to your end point.
What will be happening though is that your point of reference will seem to travel backwards related to your starting point IF you travel away from your starting point.
So you move with FTL from A to B, then you will see A's past light, which you overtook while traveling to B, arriving at B, thereby seeing your past "as happening now", but only at point B. But the time will still be ticking forward. And while you travelled to B, you raced against the light coming from B, meaning you travelled faster into the future of B.
If you then travel back with same speed from B to A, you will still be in the future from when you started in the first place. But you will see yourself standing at B. And again, while travelling from B to A, you raced against the light coming from A, meaning you saw that future happening at FTL speed.
Even moving with 10 times the speed of light, you still take “forward time” to move to your end point.
There’s no such thing as speeds faster than light—the worldlines of objects with such trajectories are called “spacelike” instead of “timelike” for a reason. “Forward” and “backward” time is only defined for events within your light-cone, and trajectories “faster than light” are outside it. Whether events outside your light-cone are in your future or your past are dependent on your current reference frame, which you can change at will by accelerating—so spacelike trajectories have no intrinsic direction with respect to time.
The thing about “moving with FTL from A to B” is that if B is far away, the event at B simultaneous with your departure from A will be highly dependent on A’s reference frame—a shift in A’s velocity will correspond to a shift in B’s timeline equal to (vx/c^2^)/√(1-v^2^/c^2^) (where v is the change in A’s velocity and x is the distance to B). And things are changing velocities with respect to each other all the time (e.g., for objects on earth due to the planet’s revolution and rotation around the sun), so the point in B’s timeline at which you’d arrive would be constantly swinging backward and forward in time.
And the same is true for the return trip: a minor change in B’s reference frame can put your arrival back in A’s timeline at a point before your original departure.
I can imagine such a scenario as well because we are humans and we would do dumb shit like that.
FTL can mean different things. It could be the Trekkian warping space around you. It could be the Galactican jump to somewhere else. Or a portal. Or something else. Which tech it will be will matter. And different to most sci-fi, there could be more than one way if indeed c can be smashed.
The problem with space is that it isn't completely empty and stuff in it moves like evil landmines. You don't want to warp into a moon or jump inside an asteroid belt. Which means you will need this sort of highway or scenic spot system of space that is actually confirmed empty so travel along the route doesn't blow you up or jumping doesn't mean you accidentally end up in a black hole. In my mind, that would prohibit the use of the technology inside a star system because there are two many moving parts to consider and keep track of. So you need to take a year-long sub-LTS access ramp to reach the highway at the edge of the solar system before you can move safely faster than a flash. The same is true for the resource rich destination.
That's why I can also imagine a scenario where having the technology might not be as impactful as we fear and thus not lead to war. The infrastructure would have to be so massive to make this work, it isn't an immediate advantage to have it. More of a burden really, provided the economy still roughly works as it does today. And if we have the tech to reach the edge of our solar system in a shuttle bus service kind of way, we will be already enlarging our resource pool with stuff we find inside our solar system in an early Expansian kind of way. Better ROI on that than stuff from further away.
The Foundation books have something similar where ships can't make jumps too close to planets. Characters sometimes complain about crossing the entire galaxy in nearly an instant then spending days slowly using impulse to get near the planet
I don't think wars would break out over the tech itself, since it's a technology that is more beneficial when shared. But if it used some super rare resource for power/fuel, we would sure as shit fight over that.
Exactly. Some wars have fought over territory, and finite resources like oil or water, and it's not far off that a discovered rare commodity in a distant planet may become a bone of contention.
Don't worry, we would make FTL weapons and solve the problem.
If they ever somehow did manage to invent FTL travel, they'd just upgrade humans from the status of conscious intelligent beings into a stream of FTL particles to supercharge their AI/Quantum Computers..
Quantum entanglement is real. Instantaneous transmission of spin states between entangled particles. So information propagating faster than light. We can detect gravity waves. The things science has yet to discover might actually be infinite. Will we ever be able to move a human being, intact, faster than light? If science advances enough, will we even need to?
While non locality is weird, it can’t actually be used to transmit information. Any attempt to force an entangled particle into another state breaks the entanglement. So you can’t really transmit any information between the two.
We do not have FTL info transfer. That's not a thing. It breaks casualty.