[MOARDONGZPLZ]

The craziest thing to me is that if we sent a generational spaceship there that was expected to take 1,000 years, it seems likely that better technology would allow the next generation of spaceships to get there much faster. So by the time the 1,000 year spaceship arrived, there would already be people there!

[nerfhammer]

This is a known paradox, I forget what it's called though. The concept is that it's arguable that any long-term space travel is pointless because there will always be a faster ship surpassing it as the originating civilization improves its technology, and so on for that faster ship. So, it's irrational to ever launch anything...

[uptown]

Apple has adopted a similar philosophy with their MacBook Pro line of computers.

[mkhalil]

I haven't laughed so much in days. Thank you.

[ChristianBundy]

This is known as the incessant obsolescence postulate: http://arxiv.org/abs/1101.1066

[kamaal]

>>This is a known paradox >>So, it's irrational to ever launch anything...

That faster ship just won't appear out of the blue.

You need to launch slower ones to get to the faster ones.

Its like the original inventor of the car opting not to build it because someday there would be a Ferrari.

[cgriswald]

Improving the speed of a 1000-year ship may only require improvements in propulsion or structure (lighter ships). There are nearby incentives to create better propulsion and structure. We do not necessarily have to launch a 1000-year ship to create a 500-year ship.

[7Z7]

But you don't have to send your people 1000 years away.

[cnp]

Yup -- This is precisely the answer to the question, so it thus remains an unresolvable paradox.

[mikeash]

Seems like you'd reach a point where it becomes worth it even with continuous improvement. If the speed of light really is a speed limit, then you'll get to a point where the maximum theoretical improvement is still some small amount. If there's a way to go faster than light, then you'll get to a point where it only takes two seconds to get to your destination.

[dmurray]

Even without the speed limit, you can expect to reach this point. Let's say your technology gets 10% faster every 25-year generation, you should launch a 200-year trip but not a 250-year one. We'll probably keep improving at that pace or better for a few iterations at least, but eventually space travel will be a stable technology, speed improvements will be rare and incremental, and 1000-year journeys will be justified.

[mikeash]

Right, barring time travel, once you can make the voyage at all, you'll always reach a point where it makes sense to depart on it. If you invent technology that takes a million years to arrive, then you have a maximum deadline of a million years. Past that point, even instantaneous travel won't be worth waiting for, if your goal is simply to get there as early as possible.

[jackcosgrove]

> So, it's irrational to ever launch anything...

Sounds like the interstellar version of Zeno's paradox.

[utku_karatas2]

On a tangent with this topic, you guys should treat yourselves with a short sci-fi story named "The road not taken".

[semi-extrinsic]

I just finished reading the entire novel series that Turtledove spun out of that short story concept. It's really good, well-researched and imaginative.

[gengkev]

But technology that would be able to send spaceships significantly faster would probably cost significantly more, so it might not be worth pursuing given the cost.

[phkahler]

Moore's law never stopped anyone from making chips with current technology.

[maerF0x0]

Or maybe they'd rendezvous and bring them "up to speed" so to speak ?

[platz]

it would be better to just 'seed' the tiny starshot spacecraft with human embryos that could litter the planet and then develop on arrival.

[jcoffland]

Right because human babies let alone embryos do so well on their own.

[platz]

that's why we also send self-replicating nanobots along with them.

[jcoffland]

For their extensive experience in child rearing.

[platz]

no problem, we train them with a convolutional neural net w/ examples from earth to provide for them. should suffice until about an age of 7 after which they'll just continue to use the nanobots to provide raw materials.

[jdmichal]

See James P. Hogan's Voyage from Yesteryear. It involves a post-scarcity civilization seeded in much the way you suggest.

https://en.wikipedia.org/wiki/Voyage_from_Yesteryear

[ju-st]

Adults from later, faster spacecrafts could raise the babies.

[bdamm]

Why wouldn't they just bring their own? Or make some?

[platz]

we'll also send send self-replicating nanobots

[flukus]

If you're limiting it to generational ships then there isn't much improvement to be made, we can still only accelerate at ~1G. The only variable is how long that acceleration can be maintained.

[scotty79]

It was a theme it this cartoon: https://en.wikipedia.org/wiki/Once_Upon_a_Time..._Space

[lifeformed]

Maybe there could be a kind of factory-ship that was built to be self-improving, so during those 1000 years it would improve itself and increase it's speed.