Are generation ships inherently implausible?

So I've been thinking about the idea of a series that takes place on a small fleet of generation ships, traveling at around 10% of lightspeed to Proxima Centauri, which should take around half a century. So the flaws here have been pretty well laid out in detail by Kim Stanley Robinson here, who also wrote the book Aurora with the same argument. While I think his problems have solutions, these solutions lead to another problem: Anyone who is capable of building a working generation ship has no reason to do so.

In order for generation ships to work, you essentially must have fusion power and nearly perfect self contained life support. You also need genetic engineering to fight evolutionary pressures as well as either transhumanism or medicine advanced enough to deal with damage from stellar radiation and the possibility of major ecological problems.

All of this basically gives you the ingredients for a post-scarcity utopia, which people have to then leave to go on these ships in which scarcity comes from the fact that you only have whatever you started with. On the upside this does solve another major problem, that we have no idea whether there are any habitable destinations, as we can simply live in space within the new solar system. On the downside, if you have all of these, you then have nearly infinite growing space within our own solar system and thus no real reason to leave in the first place.

This post scarcity context does at least solve one problem without any major downsides, it means that there is no real need for anyone back home to turn off the lasers that allow your such a ship to be a somewhat workable beam-rider. Alternatively it could also allow you to synthesize enough fuel even with insane mass ratios. There is also a really cool means to slow down, called the magnetic sail.

Anything I'm missing?

EDIT: One major point I failed to make fully is that when I say live in space, I mean to live in newly constructed habitats in the new solar system, not to remain on the ship itself. Also, I think the deeper problem is the lack of habitable destinations that we know of. Either the world will be uninhabitable, in which case it will need terraforming that could last centuries, or it will be habitable and almost certainly have something alive on it. Specifically a dead world would never have oxygen (like Mars, it would turn to rust). The better question then becomes what is the point of traveling to a new solar system just to live in space stations?

EDIT2: I finally corrected the travel time. My original mistake was using delta-v instead of speed, which would effectively cut the travel time in half using a variation on the flip and burn style popularized by The Expanse.

posted almost 5 years ago

Adam Reynolds‭

1 reputation 8 0 0 0