Aliens in the Oort? one possible explanation of the Fermi paradox.

[Mechalich]

While this technically breaks the negative sum economy problem, I don't know that it's sufficient for long generations. If you spend five generations or more all becoming writers and actors, what happens when you get to the far side, and other things are needed again?

Well, it depends on technology level. Launching a generation ship with today's technology would be a very bad idea, certainly, but what about a century from now in a hypothetically nanofabricated, 3D-printed, AI-mediated accelerated future? Then things start to look rather different. It also depends on how far you're going compared to human lifespan. If the course is a 60-year journey a single dictator can control society on a ship the entire time (and with fairly modest life-extension tech you can stretch this to 80 or 100 years).

Also, it's perfectly possible to launch a generation ship below capacity, which allows for economic and population growth within the system without straining resources. You'd certainly want more people on arrival at a new planet than at departure. This is really the same principle as using cryogenics to haul a 'colony population' while a small maintenance crew actually runs the ship.

Going more broadly, one reason to raise the issue of generation ships is that a starship traveling at 0.1c is feasible within our understanding of physics and engineering. It would be huge, ridiculously expensive, and all sorts of other messes to build, but some kind of fusion rocket operating at that speed is at least plausible. Certainly sending machines from star to star at that speed is viable, even if making a ship large enough to safely transport humans is more challenging. As such it's possible to consider travel time from star to star in decades, but less than that pushes hard on the bounds of the possible.

[Bohandas]

I suppose it could be ok if you had a ship like the Axiom from Wall-E, but then that raises the converse question of why you would ever land, except maybe briefly to refuel if you were dependent of uranium or whatever.

Getting on AND getting off would be limited to a specific window of technological advancement

Press gangs and conscript militaries happened. Australia happened. Hostile architecture and other measures to deter the homeless are things. Mars One fell apart, but thousands of people signed up for what they were explicitly told was a one way trip.

The journey itswlf doesn't last most of your lifetime in that situation. Plus, you're still in meaningful contact with earth; IIRC the transmission time for to send a signal from Mars to Earth and back maxes out at like an hour and a half, which isn't fast compared to what we're used to on the internet but is still way faster than express mail.

[LibraryOgre]

I still hold that machine probes are a lot more likely than generation ships.

I absolutely agree with this.

But in addition to those with incorrigible wanderlust, some people might be pressured onto the ship as a way for a society to exile malcontents and undesirables while trying to put a good optics spin on the whole deal.

I mean, there's certainly precedents for "send these people far away" or "let's get the hell out of this location, even though the journey might kill us."

Heck, it worked for the Golgafrinchans.

[Mechalich]

I absolutely agree with this.

I think there's a pretty clear multi-stage process. The first stage is to identify some place you actually want to go using telescopes - whether that's colony planets or alien life or whatever. The second is to confirm the data with machine probes. Then the final stage is to find some way to send actual people.

I mean, there's certainly precedents for "send these people far away" or "let's get the hell out of this location, even though the journey might kill us."

It's admittedly rather hard to come up with any sort of justification for sending people to another star system. Equally, interstellar colonization is kind of a hard sell, since there are almost certainly better options closer to home (including space habitats). The best one I can think of is actually discovering alien life. People would absolutely volunteer to travel to another star to study an alien ecosystem, regardless of whether or not there was intelligent life, and fully in acceptance that it would be a one way trip. After that it comes down to how such a thing could be accomplished.

[Bohandas]

The best one I can think of is actually discovering alien life. People would absolutely volunteer to travel to another star to study an alien ecosystem, regardless of whether or not there was intelligent life, and fully in acceptance that it would be a one way trip. After that it comes down to how such a thing could be accomplished.

Well that works for relativistic ships, but my issue is with generation ships. People would absolutely volunteer to travel to another star system even without an alien ecosystem, but my issue is that far fewer people would be willing to travel partway to another star system and then probably be turned into Soylent Green

[Mechalich]

Well that works for relativistic ships, but my issue is with generation ships. People would absolutely volunteer to travel to another star system even without an alien ecosystem, but my issue is that far fewer people would be willing to travel partway to another star system and then probably be turned into Soylent Green

That's why I specified short journeys, ones that most of the initial participants could be expected to survive. A generation ship that takes thousands of years is indeed highly unlikely to work. By contrast a ship that takes 80 years, with children born close to destination so they have just entered adulthood upon arrival make significantly more sense. Especially if the destination star system is not immediately habitable - which is likely since compatible garden worlds are going to be incredibly scarce - and some additional decades living on the ship are necessary before planetside or asteroid base habs can be fabricated.

Now ideally you'd send machines ahead to fashion a nice space habitat for the travelers use upon their arrival, but that might be difficult to coordinate.