Talk-Polywell.org

zDarby wrote:Of course, if a 1g reactionless were available, we'd be colonizing the entire solar system in only a few decades. That'd be pretty awesome!

If we had a drive that could deliver 1g for an indefinite period, we could colonize the stars. Trip times would be a matter of months to years, ship time, but doable.

You would need a lot of information about a planet before you'd try to colonize it, meaning many missions to it previously, and the odds of finding a suitable planet within 100 light years are not especially good. I think when you look at all the practical aspects, we need to wait for warp or wormhole before trying to colonize other planetary systems and just focus on our own.

Given a "1 gee solution" there is plenty of colonizing to be done right here in our system, and the ability for everyone to travel in space just as they do in air right now would change everything. I don't think people understand the profound impact on humanity there would be for everyone to be told "yes you can' instead of "no you can't". Think of what it means to motivate 8 billion people. . .

Skipjack wrote:I have no pitty for some microbial life. My main concern would be that it could turn out to be a pathogen.

If you could travel back in time, say, 2 billion years ago, and some Martian Areoformer had just landed on Earth with a desire to wipe out your microbial ancestor, would you cheer him on?

If we had a drive that could deliver 1g for an indefinite period, we could colonize the stars. Trip times would be a matter of months to years, ship time, but doable.

You can reach the speed of light by accelerating at 1g for a year. Still a long time to reach habitable planets.

and the odds of finding a suitable planet within 100 light years are not especially good

Well, we havent really looked there yet and looking at the star systems that we have checked, the odds are not THAT bad at all.
Recent discoveries actually say that it is quite likely.

A single century of biotech progress might completely change the parameters for these estimates.

If you could travel back in time, say, 2 billion years ago, and some Martian Areoformer had just landed on Earth with a desire to wipe out your microbial ancestor, would you cheer him on?

This is a non sensical example.
1. Timetravel, especially back in time is impossible with maybe the exception of merely a passive observer.
2. You can only judge from what is, not from what may be. It is just as likely that (even of there are any) these martian microbes will never develop into higher lifeforms (they havent done so in billions of years).
3. If there was such a Martian Aeroformer who landed on earth 2 billion years ago, then I would have to be the result of that, or otherwise I would not exist to travel 2 billion years back in time to meet him.

You can reach the speed of light by accelerating at 1g for a year. Still a long time to reach habitable planets.

As I said, ship time. Time dilation piles on.

You would need a lot of information about a planet before you'd try to colonize it, meaning many missions to it previously, and the odds of finding a suitable planet within 100 light years are not especially good

If it takes years to get there, you take your time to study the planets you find there. You don't make hit and run studies.

That assumes you insist on colonizing a planetary surface. I'm already assuming a ship that can support a crew for a few years getting there. It may not be a huge step from there to a permanent colony.

Skipjack wrote:1. Timetravel, especially back in time is impossible with maybe the exception of merely a passive observer.

Not if you allow multiverse splits at points of meddling.

Skipjack wrote:2. You can only judge from what is, not from what may be. It is just as likely that (even of there are any) these martian microbes will never develop into higher lifeforms (they havent done so in billions of years).

But, any one of them could be a pre-Skipjack. You could just kill the ones that don't blog.

Skipjack wrote:3. If there was such a Martian Aeroformer who landed on earth 2 billion years ago, then I would have to be the result of that, or otherwise I would not exist to travel 2 billion years back in time to meet him.

Unless you shot him.

(Best Will Smith imitation)
"Yo! Green and purple thing with the portable lab kit. Back away from great, great, great, great, ... <1e+23> ... great, grandpa. Now! <KA-BLAMM!>"

OK, to get back OT, here's some SpaceX info:
Euroconsult: Five Minutes With SpaceX

Some good lines in there, like:

"GS: I don't have any intention of putting anyone -- well, I don't have any intention of putting Astrotech out of business."

And:

"AWST: Why the octagonal arrangement on the engines on the upgrade?

GS: As opposed to the tic-tac-toe? You actually want the engines around the perimeter at the tank, otherwise you're carrying that load from those engines that aren't on the skin, you've got to carry them out to the skin, cause that's the primary load path for the launch vehicle. So you really want those engines out on the skin anyhow.

AWST: Why wasn't that done initially?

GS: Well, we learned a lot of stuff [with Falcon 9]."

Nice to see progress at any rate.

As for the other stuff, I tend to agree with Skippy that prospects for habitable planets within 100 LY aren't terrible given the last decade and a half of discoveries of planets - including rocky planets and star systems with asteroid belts similar to our own (inner belts, Kuiper/Oort Cloud analogues, etc).

However, Skipjack, I don't share your certainty that time travel is impossible. If FTL travel turns out to be possible, then what we know about relativity suggests that time travel is also possible. The two main ways of theoretically dealing with the implications of this are (1) multiverse, as mentioned above, and (2) chronological protection mechanism - which is probably what you mean when you say a passive observer might be allowed.

However, the universe often turns out to be stranger than we think, and perhaps it just allows paradoxes. (The physics are just too undeveloped to say if FTL happens, there would for certain be a chronological protection mechanism.) And, there's always the theory that the history we know *is* actually the result of interference from time travelers, but for some reason we're not aware that they're time travelers.

Hard speed of light speed limit or chronological protection mechanism seem the most sane positions, but weird things happen.

Anyway, I found DeltaV's thought experiment reasonable. Often philosophical thought experiments make no claim to be physically feasible - the point is the morals/ethics/theory of society or realism being discussed. Is there a reason to assume that if viral/monocellular/simple invertebrate life has stayed stuck at one stage for a couple of billion years, it won't evolve in the future? Do you, or any of us, have a right to exterminate or utterly alter an entire species or ecosystem simply because we deem it "primitive?" Perhaps we may be able to make a very good case to answer "yes" to such questions, but it seems to me to be a philosophical debate worth having, rather than just hand-waving any ethical concerns away.

And yes, we alter other species and ecosystems on Earth the whole time, and drive some critters and plants to extinction. i think that the primary ethical distinction between that situation and the situation on other planets is that we evolved here, and were part of this ecosystem all along - so mucking about with our own system isn't as bad as tearing into one which has been completely separate.

Also agree with Betruger - biotech and nanotech might make it possible to seed planets with suitable rocky cores with specifically tailored swarms of organisms and/or robots that can terraform them quite rapidly. Or, alter terran life to live in different environments. So, such tech potentially significantly increases the number of "habitable" planets. Again, the ethical dilemmas emerge if there is already native life adapted to those habitats.

CaptainBeowulf wrote: Is there a reason to assume that if viral/monocellular/simple invertebrate life has stayed stuck at one stage for a couple of billion years, it won't evolve in the future? Do you, or any of us, have a right to exterminate or utterly alter an entire species or ecosystem simply because we deem it "primitive?" Perhaps we may be able to make a very good case to answer "yes" to such questions, but it seems to me to be a philosophical debate worth having, rather than just hand-waving any ethical concerns away.

And yes, we alter other species and ecosystems on Earth the whole time, and drive some critters and plants to extinction. i think that the primary ethical distinction between that situation and the situation on other planets is that we evolved here, and were part of this ecosystem all along - so mucking about with our own system isn't as bad as tearing into one which has been completely separate.

Yeah, debates are usually worth having. But I see this pretty simply:

The future is unpredictable. It is the responsibility of life forms to survive. There is a huge threat of Earth destruction in the future. As the most capable life forms on this planet, we should provide for our continuance.

Perhaps the hypothetical Martian microbes could possibly evolve one day into advanced beings. But you have to work with what knowledge and resources are available to you at the time. The idea that we abandon another world that could be made suitable to our form of life on an off-chance in the future that very primitive life forms may evolve someday is pretty stupid.

Look at life on this planet. Your ancestors are the winners of uncountable such contests that lead all the way back to the beginning of life here. Why stop that at the edge of our world for microbes? One could view such reluctance as a genetic defect, doomed to die off and abandon Earth to eventual doom.

I understand the flip-side too. Humans have morality. I think that is an admirable and noble trait in us. You could extend that morality to other life forms too, such as other humans, equivalent ETs, higher animals, maybe even some advanced plants if you go "out on a limb" (heh). But to extend that to mindless microbes over the fate of your own survival is taking it too far. Worse than your average tree-hugger.

Us Earthlings could be the result of earth being invaded by Mars, which would mean we were just going home.

discussed. Is there a reason to assume that if viral/monocellular/simple invertebrate life has stayed stuck at one stage for a couple of billion years, it won't evolve in the future?

It could, but given that without the help of humans, the environment on Mars wont actually get habitable, I dont think it would.
Dont get me wrong, I do think that DeltaV and you do have a point to some extent here. But, on the grander scale of things, I believe that humans as a species have to look out for themselves first.
Besides, I am sure the microbes would not hesitate to kill us first, if they could

A parasite that kills its host doesn't survive in the long term, so it's in our microbes' best interests not to kill us off...

Tell that to the Social Welfare Sponges.