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The Challenge of Relativistic Spaceflight

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Re: The Challenge of Relativistic Spaceflight

#61

Post by Houshalter »

snowwrestler wrote: post #32
cousin_it wrote: post #25

What's the point of these huge generation ships? It's not like there's not enough atoms on other planets. You should send a tiny fast robotic ship, maybe with an uploaded mind if your AI tech isn't good enough. It will mine materials at the destination and build a receiver antenna. Then you can send more uploaded minds by radio, which will arrive at the speed of light with low energy cost. Another reason why you shou…

If we're going to stipulate fantastic concepts like "uploaded minds" then let's just invent a hyperspace engine too and solve all the problems at once. In the real world, we want to send human bodies because that's what human minds are. Cartesian duality is a religious/philosophical concept for which no scientific basis has yet been found.

>If we're going to stipulate fantastic concepts like "uploaded minds" then let's just invent a hyperspace engine too and solve all the problems at once.

We don't know if breaking the light-barrier is possible regardless of a civilizations level of technology. Brain uploading will certainly be enormously complex and a fantastic feat of technology, but it's certainly possible based on everything we know.

Yes it's possible there is more to consciousness than just the physical brain, but that's such an absurd and outlandish assertion, it isn't remotely worth the time to worry about it.

Re: The Challenge of Relativistic Spaceflight

#62

Post by cousin_it »

snowwrestler wrote: post #32
cousin_it wrote: post #25

What's the point of these huge generation ships? It's not like there's not enough atoms on other planets. You should send a tiny fast robotic ship, maybe with an uploaded mind if your AI tech isn't good enough. It will mine materials at the destination and build a receiver antenna. Then you can send more uploaded minds by radio, which will arrive at the speed of light with low energy cost. Another reason why you shou…

If we're going to stipulate fantastic concepts like "uploaded minds" then let's just invent a hyperspace engine too and solve all the problems at once. In the real world, we want to send human bodies because that's what human minds are. Cartesian duality is a religious/philosophical concept for which no scientific basis has yet been found.

I think you have "fantastic" and "real world" backwards. The Blue Brain project is planned to have an uploaded rat brain this year (2014). Uploading human minds is very likely to be closer than capturing the whole energy output of the Sun, which is discussed in the OP.

Though uploading will likely cause so many changes that space exploration will seem insignificant in comparison, see Robin Hanson's "The crack of a future dawn" [1] and Carl Shulman's "Whole brain emulation and the evolution of superorganisms" [2]. In general I think most people don't take this scenario seriously enough, the authors I mention are the rare exceptions.

[1] http://hanson.gmu.edu/uploads.html

[2] https://intelligence.org/files/WBE-Superorgs.pdf

Re: The Challenge of Relativistic Spaceflight

#63

Post by Houshalter »

Tloewald wrote: post #33
ryandrake wrote: post #24

TL;DR: Chemical propulsion is a dead end. But, the alternatives require matter/energy of ridiculous scale (hundreds of times the power output of human civilization, launching hundreds of millions of tons of matter into orbit). We're not going anywhere, any time soon.

Not just magnitude but duration. Name one machine that works without major overhaul for more than 100 years. For bonus points, name a machine that's significantly more complex than a clock.

Name one machine that's designed to work for over 100 years.

Many of NASA's spacecraft have survived well beyond their intended death dates, because they were constructed so well, and because space is cold, static, and good at preserving things.

Re: The Challenge of Relativistic Spaceflight

#65

Post by darkmighty »

Tloewald wrote: post #33
ryandrake wrote: post #24

TL;DR: Chemical propulsion is a dead end. But, the alternatives require matter/energy of ridiculous scale (hundreds of times the power output of human civilization, launching hundreds of millions of tons of matter into orbit). We're not going anywhere, any time soon.

Not just magnitude but duration. Name one machine that works without major overhaul for more than 100 years. For bonus points, name a machine that's significantly more complex than a clock.

You're unlikely to see any project designed to last more than a few generations simply because the original stake holders won't live to it's end. Also, there's the opportunity cost -- technology usually advances which makes the investment retroactively not worthwhile.

Re: The Challenge of Relativistic Spaceflight

#66

Post by Florin_Andrei »

asgard1024 wrote: post #23

One challenge to relativistic spaceflight is computing. If you put a CPU into a vehicle, which goes close to speed of light, it may not work properly, because the energy pulses in the device will become unsynchronized when going in different directions.

Nope. All different parts of the starship are at rest relative to each other. No such effects would occur.

You seem to believe in the existence of an absolute frame of reference that all speeds are measured against. There is no such thing. "Speed" only exists as a relative measure.

Re: The Challenge of Relativistic Spaceflight

#67

Post by darkmighty »

cousin_it wrote: post #62
snowwrestler wrote: post #32

Earlier quoted context omitted.

If we're going to stipulate fantastic concepts like "uploaded minds" then let's just invent a hyperspace engine too and solve all the problems at once. In the real world, we want to send human bodies because that's what human minds are. Cartesian duality is a religious/philosophical concept for which no scientific basis has yet been found.

I think you have "fantastic" and "real world" backwards. The Blue Brain project is planned to have an uploaded rat brain this year (2014). Uploading human minds is very likely to be closer than capturing the whole energy output of the Sun, which is discussed in the OP. Though uploading will likely cause so many changes that space exploration will seem insignificant in comparison, see Robin Hanson's "The crack of a fu…

The Blue Brain project will have a rat brain model. It reproduces some of the responses you'd expect from a real. That's orders of magnitude of technical progress away from what an upload would require. We don't even know for sure if it's physically possible to perform an upload (due to quantum mechanics), much less have a device which can come close to measure a significant part of the quantum state of a working brain (i.e. the technical problems beyond physical feasibility).

Re: The Challenge of Relativistic Spaceflight

#68

Post by Tloewald »

ForHackernews wrote: post #35
Tloewald wrote: post #33

Earlier quoted context omitted.

Not just magnitude but duration. Name one machine that works without major overhaul for more than 100 years. For bonus points, name a machine that's significantly more complex than a clock.

http://www.wired.com/gadgetlab/2011/06/10000-year-clock/

Hence my bonus points ;-)

Re: The Challenge of Relativistic Spaceflight

#69

Post by Tloewald »

Houshalter wrote: post #63
Tloewald wrote: post #33

Earlier quoted context omitted.

Not just magnitude but duration. Name one machine that works without major overhaul for more than 100 years. For bonus points, name a machine that's significantly more complex than a clock.

Name one machine that's designed to work for over 100 years. Many of NASA's spacecraft have survived well beyond their intended death dates, because they were constructed so well, and because space is cold, static, and good at preserving things.

There are plenty of simple, well-made machines designed to work indefinitely -- e.g. doorknobs, window assemblies. Even simple, robust, well-maintained machinery tends not to last a very long time. There's a stone bench somewhere that Thomas Jefferson supposedly used to sit on that has become curved over time.

Re: The Challenge of Relativistic Spaceflight

#70

Post by kjs3 »

ForHackernews wrote: post #57
kjs3 wrote: post #55

Earlier quoted context omitted.

Never been a parent, eh?

\ shrug\ It's all sci-fi tech anyway. Artificial wombs probably aren't that far off: http://www.popsci.com/scitech/article/2005-08/artificial-wom... There's a clear demand for advanced reproductive technology, and it would offer the secondary advantage of neatly sidestepping the current abortion debate.

You're missing my point (which I suppose I really didn't make, so my bad). A child raise by machines is likely to be one seriously emotionally messed up child.
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