# The arithmetic of interstellar travel

by on May 12, 2013

There’s been a lot of excitement about the discovery of two Earth-like[^1] planets, a mere 1200 light years away. Pretty soon, I guess, we’ll be thinking about sending colonists. So, I thought it might be worthwhile to a little bit of arithmetic on the exercise.

I’m going to assume (generously, I think) that the minimum size for a successful colony is 10 000. The only experience we have is the Apollo program, which transported 12 astronauts to the Moon (a distance of 1 light second) at a cost of \$100 billion or so (current values). So, assuming linear scaling (again, very generously, given the need to accelerate to near lightspeed), that’s a cost of around \$100 trillion per light-second for 10 000 people. 1200 light-years is around 30 billion light-seconds, so the total cost comes out roughly equal to the value of current world GDP accumulated over the life of the universe.

Even supposing that technological advances made travel possible over such distances possible, why would we bother. By hypothesis, that would require the ability to live in interstellar space for thousands of years. A civilisation with that ability would have no need of planets.

On behalf of my fellow Australians, I’m going to make a counter-offer. For a mere \$10 trillion, we can find you an area of land larger than a typical European country, almost certainly more habitable than the new planets, and much closer. We’ll do all the work of supplying water and air, build 10 000 mansions for the inhabitants and guarantee a lifetime supply of food. I’m hoping for a spotters fee of 0.01 per cent.

On a related point, what should we be wishing for here? The fact that no-one has sent a detectable signal in our direction suggests that intelligent life forms similar to humans are very rare. If habitable planets are very rare, then this is unsurprising – interstellar distances preclude both travel and any kind of two-way communication. If on the other hand, the emergence of intelligent life is common, then the evidence suggests that its disappearance, through processes like nuclear war, must also be common.

[^1] Where Earth-like means somewhere between Venus-like and Mars-like.

1

Bob Pendleton 05.12.13 at 11:43 am

Sending preserved human genetic material by small spaceships might be a feasible means of spreading the human species outside our solar system.

2

PJW 05.12.13 at 11:53 am

“no one has sent a detectable signal in our direction”

Synchronicity as just a few days ago I was thinking about the Pioneer plaque that Carl Sagan helped make possible. I asked a couple of people in their 20s if they knew about this plaque and neither did. I’m in my early 50s and remember it well.

3

Mao Cheng Ji 05.12.13 at 12:10 pm

“Sending preserved human genetic material by small spaceships might be a feasible means of spreading the human species outside our solar system.”

What a horribly and senselessly cruel thing to do, to a little innocent planet.

4

Tim Worstall 05.12.13 at 12:18 pm

“assuming linear scaling (again, very generously)”

Not generous at all, very mean. Getting from Earth surface to Earth orbit takes the vast majority of the energy. Getting from Earth orbit to the Moon is relatively trivial.

“By hypothesis, that would require the ability to live in interstellar space for thousands of years. A civilisation with that ability would have no need of planets.”

That’s entirely true though.

Which bit are you offering up btw? Nullabor or something? Don’t you have to pay us to take that?

5

Ted Lemon 05.12.13 at 12:21 pm

Once moving at a steady speed and in a straight line, an object will continue moving at a steady speed and in a straight line until acted upon…

6

Ted Lemon 05.12.13 at 12:23 pm

Oh, also, one wants to spread out to avoid extinction by gamma ray burst. This requires one to spread out quite a lot. A space habitat will not help, and 2k light years is a pittance.

7

Anarcissie 05.12.13 at 12:31 pm

We can expect humans, if they don’t annihilate themselves in the next few decades, to disperse outward from the Earth at just a little less than the speed of light. There goes the galaxy. Look up at the unbesmirched heavens while you can.

8

Neil Levy 05.12.13 at 12:34 pm

There is a third possibility; that intelligent life is common, but that the development of science requires the right sort of conditions. Some historians of science maintain that in the 17 century doctrines that were close enough to be true to be getting on with came to be accepted by thinkers, but that there was little real evidence that they were true. If anything like that is true, then the development of science depended on a lucky and unlikely set of circumstances.

9

Chris Williams 05.12.13 at 12:52 pm

I’m guessing the Australian claim to the Antarctic. As for the bigger question of the Drake Equation and the Fermi Paradox, clearly there’s a filter. Let’s hope it’s in our past rather than in our future.

Any sucessful colonising voyage is going to be of people who can live, and prosper, in space. Hence they are unlikely to be looking for earth-like planets, and thus likely to be aiming a lot closer than 1200ly. For those interested in the broader topic of interstellar travel, Paul Gilster’s website ‘Centauri Dreams’ is worth a look. Me, I only want to go to 550 AU, so as to be able to see a little of what’s out there.

10

Rich Puchalsky 05.12.13 at 1:48 pm

Not that I’m one of those techno-utopians or anything, but this arithmetic is very questionable. It’s not merely a matter of energy cost being largely at the beginning. If someone is going to do long-distance far-below-lightspeed space travel, the two main possibilities are to either have a functioning society on the ship, or a group of frozen colonists on the ship that are woken up by machines at the destination.

In either case, people on Earth aren’t paying for the whole trip. They only pay to build the spacecraft. If there’s a society on board, they take over costs from then on. If there are frozen colonists, then the length of the trip is essentially irrelevant from their point of view, as long as the automatic revival machinery lasts. And presumably the ship isn’t going to burn fuel the whole time so the cost isn’t directly proportional to the distance at all.

Alternatively, the people on the spacecraft could try to minimize apparent travel time by going up close to lightspeed and using relativistic time dilation effects. That could mean a lot of fuel, but presumably it wouldn’t be used unless there was a cheap way of supplying that at the start or using a ramscoop or something.

11

phosphorious 05.12.13 at 1:59 pm

. . .almost certainly more habitable than the new planets. . .

Almost:

12

Christiaan 05.12.13 at 2:04 pm

“almost certainly more habitable than the new planets”

Did you take climate change into account?

13

Watson Ladd 05.12.13 at 2:10 pm

What misanthropy! The eventual stagnation and extinction of the human race is not to be preferred to ongoing exploration and discovery. It’s been 40 years since a man walked on the moon, and almost as long since an expansion of the social safety net. The connection between the two, and the neoliberal attitudes to organisation, is I think a crucial factor.

14

b9n10nt 05.12.13 at 2:26 pm

Hmmm…an economist tackles space travel. Can we assume a wormhole?

15

Tzimiskes 05.12.13 at 2:52 pm

“The fact that no-one has sent a detectable signal in our direction suggests that intelligent life forms similar to humans are very rare.”

While we’re deep in speculative territory either way, I personally have doubts about this assumption. The earth has already become much quieter than it was 50 years ago. Why should we assume that any alien species would continue to use radio signals and other easily detectable means of communication when we’ve already changed how much energy we’re sending off into space in such a short time? It may very easily be the case that the time frame in which a civilization sends off detectable signals is very short when measured against the life of that civilization. In that case, our means of detection might only be appropriate to a very brief phase in technological development rather than appropriate for the detection of technological civilizations in general.

16

Bruce Baugh 05.12.13 at 2:58 pm

Peter Ward and Donald Brownlee make an argument in Rare Earth: Why Complex Life is Uncommon in the Universe for splitting up “habitable” into some distinct categories. They note that very simple life seems to emerge about as soon as it’s physically possible for it to do so, and to go live just about everywhere it’s physically possible to do so, even in places we used to think there just wouldn’t/couldn’t be anything thriving. But the thing is that having a long thriving history of bacteria is no guarantee that you’ll ever get multi-cellular life, let alone anything complex enough to make the tools necessary to send and receive signals across interstellar distances. Bacteria (and monera and so on) are rugged things. Multi-cellular life has a tendency to fall over and die when the environment gets harsh, either acutely or chronically.

We’ve come close to the extinction of all complex life here on Earth several times, and there doesn’t seem to be any sign that the close calls we’ve had represent the ceiling on how harsh extinction events can be. It’s not at all clear that the universe as a whole has the patience to leave life-bearing worlds alone long enough to get things like us going very often.

17

gwern 05.12.13 at 3:05 pm

> So, assuming linear scaling (again, very generously)

And by the same ‘very generous’ logic, we can infer that the Pioneer was the single most expensive space program ever conducted, and as Pioneer 10 & 11 travel ever further outward from the Sun, the program is getting *more and more* expensive; presumably it is single-handedly responsible for the federal deficit. The fools! If only we could have warned them back in 1972!

18

As others have said, this notion of ‘cost per light second’ is nonsense. You need to pull out of the earth’s then the solar system’s gravitational well. That’s the main cost, not some mythical cost per unit distance. Don’t they teach physics in Australia any more?

It’s also weird to see these half joking self lacerating comments about people being a bad sort of thing to have about in the cosmos (Mao Cheng Ji, Anarcissie). The horror, sublunary filth “besmirching” the heavens.

19

JanieM 05.12.13 at 3:28 pm

Science and technology don’t (and therefore signals) don’t necessarily follow from the evolution of complex life forms. What if the line that led to humans had died out but the line that led to whales and dolphins hadn’t?

20

PJW 05.12.13 at 3:36 pm

Somewhat OT, but there’s some interesting discussion going on about a paper that puts the origin of life billions of years earlier than when Earth began 4.5 billion yeras ago, the authors using Moore’s Law to help derive their answer.
http://rationallyspeaking.blogspot.com/2013/05/moores-law-and-origin-of-life-study-in.html?m=1

21

JesÃºs Couto FandiÃ±o 05.12.13 at 3:59 pm

+1 to the “cost per lightyear” thing, although as portrayed in the article. Because actually designing something that will keep working for several thousand years while keeping people alive and safe from the dangers of space travel has to have a cost, but right now its going to be a crap shot of estimating what it is.

I’m not sure we are ever going to figure out how to spread over the stars, not that is not a good idea, but we may very well end up screwing our chances by wasting the resources here before getting to the tech level necessary for that.

Unless I dont now, we get to world peace and transform the nuclear arsenal into Orion ships. Fat chance.

22

Bruce Baugh 05.12.13 at 4:01 pm

23

Jerry Vinokurov 05.12.13 at 4:08 pm

Not that I’m going to defend the idea of sending people to exoplanets as feasible, but yeah, the linearity assumption is way wrong. There’s another way that it’s wrong though besides just the physics; I find it hard to believe that the research costs are linear as well. Although the research project of constructing a colony ship may cost untold trillions (let’s say), once that project is complete, the cost of actually manufacturing successive ships is not going to depend on the distance those ships are going to be traveling. At most we’re talking some difference in fuel reserves and food resources (although you can imagine scenarios where the ship grows its own food, etc.), but once the fixed cost of the research project itself is paid, after that you’re just paying a per-ship cost. There are lots of reasons why we shouldn’t do this, obviously, but I don’t think any of them have anything to do with the cost of space travel per light second.

24

Hector_St_Clare 05.12.13 at 4:12 pm

Re: Sending preserved human genetic material by small spaceships might be a feasible means of spreading the human species outside our solar system.

How do we arrange for the genetic material to be gestated, birthed, and raised to adulthood?

25

Eric Drexler 05.12.13 at 4:28 pm

Your calculation implicitly takes industrial technologies (steel, coal, manual labor…) as a reference point in considering potential human capabilities for manipulating matter and energy. I am persuaded that physics-based limits provide a more robust and relevant reference point in considering (for example) challenges on the scale of global economic development and drawing down CO2 levels. These challenges are rather more urgent than those of interstellar flight.

Regarding this, itâ€™s vitally important to understand how much can be understood: There are facts of the matter regarding the potential of future technologies, and there are methodologies for ascertaining at least some of those facts. PublicAffairs/Perseus published a book on this topic last week. It raises basic questions about how we frame 21st century problems (both old and new) and it offers some tools for thinking about them. Readers tell me that it is surprisingly accessible, and even enjoyable. It is intended to reward close intellectual scrutiny.

(BTW, my publisher insisted that â€˜nanotechnologyâ€™ appear somewhere in the title. I regard it as being, on the whole, anti-informative.)

26

b9n10nt 05.12.13 at 4:44 pm

theology : prayer :: space travel : hard sciences

27

Donald Johnson 05.12.13 at 5:12 pm

I’m agnostic on the existence of ET’s, but isn’t one possible answer to the Fermi question simply that we have no idea what a far more advanced civilization would be like? Maybe we’re like ants surrounded by human artifacts they have no way of recognizing as such. Of course I’ve also just made an assumption–that technological progress of the sort we’ve seen in the past few centuries will continue for at least many centuries more. But maybe we will soon figure everything out and even if we created strong superintelligence it will have nothing left to do and will be reduced to inventing new games it can play against itself, or simulating the future of the universe, or something of that sort. Conquering the earth and ridding it of wasteful biological organisms might be a way to pass the time, but after that boredom sets in. There’s your great filter.

28

GeorgeNYC 05.12.13 at 5:25 pm

“… why would we bother?”

Yes. Probably also written by a Theologian before Columbus’ expedition. (Setting aside for the moment the Eurocentric bias).

Why bother getting out of bed in the morning? ( I am sure there is a nice economic argument about that).

29

Josh G. 05.12.13 at 5:29 pm

The creation of a multigenerational colony ship would be grossly immoral. You’d be condeming future generations to spartan slavery for a goal they had no say in and may not care about.

30

Brett 05.12.13 at 5:33 pm

@Hector St. Claire

How do we arrange for the genetic material to be gestated, birthed, and raised to adulthood?

It would have to be some type of really advanced automated raising room for the first generation. I have no idea if that’s possible, but it has showed up in Science Fiction – Arthur C.Clarke wrote a book about a colony that was founded that way.

On the main topic-

There could actually be a large number of alien civilizations in the galaxy, but simply so separated by time and space that it’s almost impossible for them to interact with each other. We’re not blasting intelligible radio signals out into space like we used to (most of it is digital now), and even then those signals would be hard to tell apart from background noise more than a couple of dozen light-years out. The only realistic way for a distant civilization to detect us would be if we had the extreme fortune to hit their solar system with something from the Arecibo radio telescope or a focused military radar (which is extremely unlikely).

And interstellar travel doesn’t fill me with confidence. It either requires staggering amounts of energy to go even a decent chunk of light-speed, or the ability to engineer incredibly complex starships that can survive and work after centuries or even millenia in interstellar space. The former mostly relies on highly speculative technology (aside from Orion, which only gets you up to 3-5% of light speed if you want to stop when you get there), and the latter requires the type of engineering reliability we can only dream of. It could just be that most alien civilizations don’t bother sending starships and/or probes, since with the same space infrastructure and energy you could build yourself the type of space telescope array that would make astronomers weep with joy.

@Donald Johnson

Maybe weâ€™re like ants surrounded by human artifacts they have no way of recognizing as such.

It could be. I’ve always figured that would be the most simple answer to the Fermi Paradox – we just haven’t been looking long enough. We’ve only visited a fraction of our solar system with actual probes, and everything else has been pieced together from telescope imagery.

Timing matters a lot, too. If an alien probe passed through the solar system in 960 CE, we’d never be the wiser.

More generally, there’s a lot of potential limits, including some that aren’t obvious at first. I remember astronaut Don Pettit pointing out in an essay that if you were living on a planet with a radius 50% greater than that of Earth (not impossible with all the “super-Earth”-sized planets we’ve found), you wouldn’t be able to get into space with any chemical rockets.

31

Barry 05.12.13 at 5:36 pm

5.12.13 at 4:12 pm

Re: Sending preserved human genetic material by small spaceships might be a feasible means of spreading the human species outside our solar system.

Hector_St_Clare ” How do we arrange for the genetic material to be gestated, birthed, and raised to adulthood?”

After creating a complete human-compatible biosphere, that’d be easy :)

32

What price survival? Somewhere out there is a great, big rock, or a supernova, or a gamma-ray burster, and it’s got our name on it. If we’re still on this rock when it comes along, we’re gone. Do we care enough to preserve this mess we call civilisation? If not, why bother at all?

People who, quite rightly, react with disgust at those who whinge about how much it will cost to prevent global warming seem to have no problem with shooting down humans in space â€” the only way the species will, in the long run (or as long a run as there is) survive â€” as too expensive.

In my more pessimistic moods, I wonder if planets aren’t like dandelions, whose function is to provide the initial habitat and raw materials that allows for maybe one species to reach a point where it can escape out into space, where energy, room, and raw materials are essentially boundless â€” but the planet is depleted in the process, a dandelion head empty of its seeds. The species that make it off their homeworld drift into the universe and survive; the ones that exhaust their resources â€” the easily-extracted ores and energy suppliesÂ â€” without expanding into space, well, they get stomped on or sliced to ribbons in the great cosmic lawn mower.

I have a bad feeling I know which one we’re going to wind up being.

33

Brett 05.12.13 at 5:38 pm

@Josh G

The creation of a multigenerational colony ship would be grossly immoral. Youâ€™d be condeming future generations to spartan slavery for a goal they had no say in and may not care about.

You might be able to compare it to people emigrating to a new country, although I am a little bothered by the idea of having entire generations of people who know nothing but life in the ship. What if they come to identify the ship as home, and don’t want to stay on the planet when they get there?

Then again, I’m dubious about colonizing planets at all. I agree on the OP point about that type of civilization having no need for planets, since they could just as likely build large space habitats that would be far more comfortable and home-like than anything an alien world could offer. You could just save the alien worlds for the scientists and tourists.

34

William Eric Uspal 05.12.13 at 5:48 pm

Before embarking on a journey of 1,200 light years, surely we should do a little more searching in our own neighborhood. Last year, astronomers announced discovery of an earth-sized, but non-habitable exoplanet in Alpha Centauri B, four light years away. That’s within reach of current or near future technology. Perhaps it’s simply a matter of time before we find something close and habitable.

35

Substance McGravitas 05.12.13 at 5:55 pm

The creation of a multigenerational colony ship would be grossly immoral. Youâ€™d be condeming future generations to spartan slavery for a goal they had no say in and may not care about.

I think I’ve done this to my daughter. The condemning part; the colony ship’s in the garage waiting for parts.

36

fivegreenleafs 05.12.13 at 6:11 pm

Curious calculations. Let me supply two other sets for the sake of comparison,

Genome Sequencing

Human Genome Sequencing Project,
Time to completion = 13 years, (from 1990 to 2003)
Cost = 3 billion USD

Full human genome sequencing today (2013)
Time = Approx 1 day
Cost = Approx 1000 USD

This equals a cost factor reduction of 3 000 000 in just over 10 year

Raw computing power of a CPU

The fastest supercomputer in the world in 2000 was the IBM ASCI White at the DoE-Lawrence Livermore National Laboratory, California, USA, reaching 7,2 TFLOPS (i.e. 7,2*10E12 FLOPS)

It cost 110 million USD, weighted 106 ton, and draw 3 MW of power to run and an additional 3 MW for cooling totaling 6 MW.

In slight over 12 years, you can buy a standard high end Graphic Card for a gaming desk top computer for approx 500 USD, which will give you 5 TFLOPS raw computing power, that weight approx 1 kg and draws max 250 W

That equals a cost factor reduction of 275 000 in 12 years.

37

Bruce Baugh 05.12.13 at 6:23 pm

Nomad UK: Not every calamity we can predict is worth spending the sum requires to solve it. Take the Iraq War and Dick Cheney’s whole 1%-chance thing. We might spread ourselves through nearby space and still get wiped out entirely by a gamma-ray burster, or any of the myriad other galactic-scale phenomena not friendly to our continued survival. And so forth and so on.

Realistically, of course, by the time we have any technology that can get living people on other worlds, our assessment of the costs and benefits will be wildly different than any we make now. At least as different both technically and culturally as our assessments of long-distance trade are from those of Columbus and his contemporaries. Our descendants will know of hazards we haven’t even thought of yet, and will appraise ones we do know about differently, and the mix of tools they end up with thanks in part to path dependencies already laid down will lead to opportunities as well as limitations we have no conception of now.

I think it’s smart not to close off any options right now. But I also don’t think anyone now living can make real predictions about what’ll make long-term sense worth any reaction stronger than “neat!”.

38

JW Mason 05.12.13 at 7:00 pm

John Q. is right.

As advances in astronomy steadily raise our estimates for all the early items in the Drake equation, the evidence is becoming overwhelming that the Great Filter lies ahead of us. At this point, by any reasonable standard of proof we know that colonization of other solar systems is simply impossible. Given the frequency of earthlike planets, and what we know about the evolution of life on this one, if the chances of life migrating out of its original solar system were greater than zero, they’d already be here. So it cannot be done. Sorry, guys.

However, I don’t draw as pessimistic conclusions from this fact as John does. It seems clear that the technological hurdle for self-extermination of civilization on one planet is vastly lower than the hurdle for implanting it on another. (And we human beings depend vastly more on the specific ecology of earth than SF solipsism wants to admit.) And, the same expansive, dynamic, competitive impulses that lead to technological progress and, in an open space, endless expansion, in the closed space of this planet, push toward war and environmental collapse. So any society that would eventually expand to other solar systems, will wipe itself out long before then.

But it also seems to me that it’s perfectly possible to halt the process before then. If we get rid of capitalism and the state — the two main locuses of competition — there is no reason we can’t bring technological progress to a halt and establish a society that could be sustained on earth indefinitely. I presume this has happened to intelligences elsewhere. The condition of survival on one planet is to rein in the forces of competition, expansion and conflict. Which is good – it means we can finally organize society around the development of our capacities as human beings, instead of endless accumulation of stuff.

On one other point — people often talk about the importance of space colonization as insurance against extinction in an asteroid impact, etc. But I can’t help thinking, a technology that can redirect asteroids can send them towards the earth as well as away from it. The baseline probability of a massive asteroid impact on earth is very low. You don’t need to be terribly cynical view of history to think that if there were people living out there, it would be much higher, .

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JW Mason 05.12.13 at 7:07 pm

Somewhere out there is a great, big rock, or a supernova, or a gamma-ray burster, and itâ€™s got our name on it.

And a great many more that could have our name on it, if the technology to move them existed. I feel much safer on earth knowing there are no people out there.

40

Brett 05.12.13 at 7:34 pm

@JW Mason

iven the frequency of earthlike planets, and what we know about the evolution of life on this one, if the chances of life migrating out of its original solar system were greater than zero, theyâ€™d already be here. So it cannot be done. Sorry, guys.

We barely even know a fraction of what it would take to really put numbers in the first few variables of the Drake Equation. Our astronomy is impressive, but still quite limited – we just found the first planet that I really consider a serious possibility for being truly “Earth-like” in Kepler-062f recently.

As for “already be here”, how do you know they didn’t come and go in the past? We’ve been looking at the sky with something other than the naked eye for only 500 years, and humanity in general has only been around for 200,000. There’s at least another 4-5 billion years in which aliens could have passed through the solar system without us being the wiser. That’s why I always make sure to talk about separation in time and space.

More generally, I find it rather presumptuous that people think aliens capable of interstellar space flight will spam space with self-replicating machines (another speculative technology). We have no idea what they might think, or consider important to do in space. This is where someone says, “Yeah, but if there’s just one who does ” but so what? That “one” might be over in the Andromeda Galaxy, or even in another Galactic Supercluster. Or they might not have been born yet.

The condition of survival on one planet is to rein in the forces of competition, expansion and conflict. Which is good â€“ it means we can finally organize society around the development of our capacities as human beings, instead of endless accumulation of stuff.

That’s already happening with the rise of the Service Economy, the expansion of digital goods and non-physical entertainment, and so forth. We don’t see it yet, simply because so much of the world is still at the point where accumulating some physical goods would be a huge boon (read: China, India, Africa), but it’s heading that way, along with birth rates dropping towards the replacement level world-wide.

But I canâ€™t help thinking, a technology that can redirect asteroids can send them towards the earth as well as away from it.

All technology is like that. Fire can be used to cook your food and warm your home, burn down a forest, burn down someone else’s home, or burn down a forest to shape it the way you want (like with the Amerindian population of the Americas).

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JW Mason 05.12.13 at 7:39 pm

Brett-

You don’t understand the reasoning here. If it is possible to colonize other solar systems, then it only takes *one* civilization to do so for the entire galaxy to be colonized. So the Great Filter doesn’t require any presumptions about alien civilizations except that, if it is possible to settle another solar system, at least one civilization will do so. The logic of Darwinism does the rest.

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JW Mason 05.12.13 at 7:45 pm

The presumptuousness is on the side of people who think that interstellar travel is possible, and yet that *every single one* of the millions or billions of civilizations who could potentially do it, have chosen not to.

Talking about the limits of astronomy is also a sign of confusion. We have *already* established that there are is a very large number of earthlike planets out there. Further improvements in astronomy can only raise that number. And the larger the number of habitable planets, the lower the (already microscopic) probability that interstellar travel is possible, because the larger the number of civilizations that would all independently have to have chosen to forego it.

One thing that always strikes me about SF fanboys in these conversations, is how uninterested they are in science.

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Rich Puchalsky 05.12.13 at 7:49 pm

I think that the Solar System has been enclosed in a giant, artificial sphere designed to faithfully produce false observations that the universe is empty of intelligent life. It will continue to be enclosed by this sphere until such time as we stop believing that “The logic of Darwinism” implies that being able to settle other planets means that some species would inevitably grab all of them.

(No, I don’t really think that.)

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JW Mason 05.12.13 at 8:02 pm

until such time as we stop believing that â€œThe logic of Darwinismâ€ implies that being able to settle other planets means that some species would inevitably grab all of them.

And yet, it does.

45

Before getting to yakking about nearby stars with potentially habitable planets, we should remember that there are places in the solar system, places suspected to be full of liquid water, where no-one’s landed a probe. We keep going to Mars every few years because that’s at the outer edge of our technical abilities for reasonable cost, not because that’s the most promising place to do science. Maybe fifty years from now there’ll be a probe that lands on Europa or Enceladus and drills into the ice to reach the water oceans…

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Bogdanov 05.12.13 at 8:20 pm

Is the assumption that human life would be traveling 1200 light years at the speed of the Apollo vessels? Because even if you assume infinite funding and travel at the speed of light, I can assure you that a society of 10,000 people would not survive a millennium in a tin can. At least not without devolving into madness.

If human beings are ever going to travel outside of the solar system it’s going to be via some scientific breakthrough that has not yet occurred, which allows travel faster than the speed of light (wormholes or something, I don’t know…)

@JW Mason — I think your logic is flawed. Interstellar travels could still be possible, the fact that extraterrestrial life hasn’t visited Earth (OR HAS IT?!) just means that no neighboring stars have seen such civilizations evolve. The universe is a big place. You can hop between solar systems and still not get very far. Who knows what’s going on in the next galaxy over, or even just 10 solar systems over?

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Omega Centauri 05.12.13 at 8:32 pm

b9n10nt
“an economist tackles space travel. Can we assume a wormhole?”
No. But could we assume a spherical economist?

Bruce Baugh
I read the rare earth book too. I was unconvinced about the need or rareity
of having a Jupiter (to supposedly absorb enough potential impactors, to make
impact extinction sufficiently rare…). I am also unconvinced about the
need for a large moon, i.e. an unstable climate encourages adaptable life
-maybe thats what intelligence needs to emerge. But, yes I think it is
clear that worlds supporting complex life are rare. The vast bulk of
these planets we like to call “earthlike” will be barren and uninhabitable.
As “earthlike” currently means roughly the right distance from the star
(liquid surface water not ruled out), and not so heavy as to be a gas giant.

Hector_St_Clare
I really truly think the difficulty of “gestating, birthing and raising
humanlike animals, is small potatoes compared to actually getting there. I.e.
if we could solve the issues of getting there, we could solve the issue
of having the spacecraft regenerate from a database of genetic information

Josh G.
If we want to speak about morality, what are the morals involved
in spreading the planet-killing infection called humanity to other
planets capable to supporting complex life?

Actually I have a means of spreading technological civilization throughout the galaxy (whether biological -or machine), that doesn’t violate physics. All that is required that humans don’t yet have, are a power source (fusion), and interplanetary travel robust enough to allow colonization of Kuiper Belt objects. [Note a KBO is dirty ice, and contains all the needed raw materials] Once started Kuiper Belt Object colonies could spread to other KBO’s. Eventually (or deliberately) some of these objects orbits get enough of a graviational kick to escape the parent star’s gravity. Eventually one gets a chance to seed KBO’s of another stellar system. The timescale to diffuse thoughout a galaxy in this manner is only a few hundred million years.

48

John Quiggin 05.12.13 at 8:38 pm

@Bogdanov and others: One reason I think the linearity assumption is generous is that I assume the spacecraft has to accelerate to something close to lightspeed, and decelerate on the way down. That’s much more demanding than reaching escape velocity from earth.

Obviously, if you’re willing to take a million years or so over the journey, you can save a lot on fuel.

49

JW Mason 05.12.13 at 8:56 pm

The timescale to diffuse thoughout a galaxy in this manner is only a few hundred million years.

Which is how we know for certain it’s impossible.

50

Watson Ladd 05.12.13 at 9:05 pm

@JW Mason: The problem is we don’t have specific reasons why it is impossible. Yes, no one has done it, but at the same time the possibility of sending lots of Pioneer like probes that are robust enough to reactivate when passing by a star and emit some simple morse code signal isn’t ruled out by any law of physics.

In 1950 you would have predicted no one would summit Everest.

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Omega Centauri 05.12.13 at 9:26 pm

Watson, JWs logic is better than that. Since the galaxy is orders of magnitude older than the diffusion time we would expect that almost all galaxies at a given instant of time are either totally infected (it is best to think of my mechanisim as a KBO epidemic), or no infection has developed. Its nearly a binary distribution. The number in an intermediate state (spreading infection) must be small because they don’t remain that way long enough. So the fact that we have no evidence of such infection implies that the rate of genesis of such an infection per billion galactic years must be low.

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Jerry Vinokurov 05.12.13 at 9:32 pm

As advances in astronomy steadily raise our estimates for all the early items in the Drake equation, the evidence is becoming overwhelming that the Great Filter lies ahead of us. At this point, by any reasonable standard of proof we know that colonization of other solar systems is simply impossible. Given the frequency of earthlike planets, and what we know about the evolution of life on this one, if the chances of life migrating out of its original solar system were greater than zero, theyâ€™d already be here. So it cannot be done. Sorry, guys.

I don’t know why anyone would believe that the Great Filter is a thing to be taken seriously. We certainly don’t have any great amount of evidence, much less a “reasonable standard of proof,” that it is impossible to colonize other solar systems. You may feel as sorry as you like, but what you’re saying is basically conjecture and speculation; the truth is that we have no reliable data regarding the possibility of exoplanetary colonization. The universe is quite a big place, and there’s a lot about it we don’t know.

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Lee A. Arnold 05.12.13 at 9:36 pm

If interstellar travel has already been invented on another planet, then that travel is very likely to be at light speed. That has certain consequences, both for the discussion of the economic cost, and the discussion of whether or not we are alone in the universe. My logic for this is as follows: Any evolution of life on another planet will probably result in very short lifespans, as we ourselves have. This is due to the fact that evolution begins as a material cycle on a planetary surface, a cycle energized by its local star, and the frequency of the cycle will be limited to the diurnal/annual range. These energized/de-energized molecular cycles, occurring in some sort of chemical soup for available replacement parts, is the beginning of evolution, at least as I perceive the current explanation of evolution. Maybe there can evolve some thousand-year-old trees, and of course micro-organisms live forever by subdividing, but that is about all there is. Of course, after evolutionary time more advanced beings will result, with technology and so forth, and they could extend their lifespans, as we on Earth might do in another few years, due to medical developments. But they are still not going to hop into a slow starship unless they have to get out of the area (e.g., they have calculated that their star is going nova). Because otherwise they are consigning themselves to a pretty boring, long existence: quiet desperation in a tin can, in a vacuum. So I conclude that any aliens who have visited Earth, have done so at light speed. (Or very, very near it. But I’m going to assume that if they have technology that can go very, very near light speed, then they can go light speed. They do not obtain an economic problem.) Now, notice two things about light speed: One: at light speed, they would not care about traveling vast distances, interstellar or even intergalactic, because relativistic time-dilation means that the travel is instantaneous for them. Blip they are over here, blip they are over there. So they come to Earth, slow down and spy the likes of Rush Limbaugh who is leaving no crap unshat, check the “Garbage” box on the planet-ethnographic report, and they’re off: because why would you waste any part of eternity in observing this planet? Are you that goddamned bored? And two: at light speed, the aliens are transformed into electromagnetic radiation. Therefore, arguments about whether or not we are alone in the universe are looking at the wrong evidence. Aliens could be everywhere, because they would be inside the light.

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Brett 05.12.13 at 9:45 pm

@JW Mason

You donâ€™t understand the reasoning here. If it is possible to colonize other solar systems, then it only takes *one* civilization to do so for the entire galaxy to be colonized.

“Capable of interstellar travel” is not the same thing as “colonizing the entire galaxy”. We’re capable of going to Mars in the next ten years – hell, we could have done it in the 1980s, just like how the Space Enthusiasts and Von Braun thought we would in the 1960s. But we didn’t, and it looks very much like we’re not going to do it for the foreseeable future.

The presumptuousness is on the side of people who think that interstellar travel is possible, and yet that *every single one* of the millions or billions of civilizations who could potentially do it, have chosen not to.

No, the presumptuousness is on the people who assume that there must be millions or billions of civilizations, and that they know enough about what they might be like (or what technology might entail) to assume that if they merely have the capability to expand to other solar systems, then the whole galaxy is bound to fill up.

Even “colonization” is a huge assumption. Why would aliens want to live in any particular solar system, as opposed to visiting it? Why would they even want to leave their own solar system en masse?

Talking about the limits of astronomy is also a sign of confusion. We have *already* established that there are is a very large number of earthlike planets out there. Further improvements in astronomy can only raise that number. And the larger the number of habitable planets, the lower the (already microscopic) probability that interstellar travel is possible, because the larger the number of civilizations that would all independently have to have chosen to forego it.

We have established no such thing. Kepler and other observers have confirmed 885 planets, with another 2300 planet-candidates out there. A tiny handful of them (less than two dozen) have planets with a range of mass, radius, and orbital that might make it possible for them to be habitable, and even that stretches things a bit – Kepler-062e got called “habitable” even though it receives so much sunlight that it’s probably a super-Venus at best.

Occasionally you’ll hear some astronomer say that our galaxy “might have as much as 100 million earth-like planets”, but it’s just one or more of them taking the ratio of planets that might be habitable and applying it to the number of stars out there in the Milky Way.

@Omega Centauri

I read the rare earth book too. I was unconvinced about the need or rareity
of having a Jupiter (to supposedly absorb enough potential impactors, to make
impact extinction sufficiently rareâ€¦). I am also unconvinced about the
need for a large moon, i.e. an unstable climate encourages adaptable life
-maybe thats what intelligence needs to emerge.

Same here, and there have been a couple of studies more recently that cast doubt on the “protective Jupiter” idea. Apparently the worst scenario would be to have a planet with 0.15 to 0.20 times Jupiter’s mass where it is – and the best would be to simply have no gas giant there at all.

Actually I have a means of spreading technological civilization throughout the galaxy (whether biological -or machine), that doesnâ€™t violate physics. All that is required that humans donâ€™t yet have, are a power source (fusion), and interplanetary travel robust enough to allow colonization of Kuiper Belt objects.

Not exactly. You also need the ability for those interstellar ships to reproduce themselves at the destination in order to send out more ships into interstellar space. That’s speculative at best, since right now it takes an entire technical society just to produce rockets capable of moving significant mass into orbit. We can only speculate about what type of infrastructure it might take to build spaceships capable of traveling in deep space.

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Will Boisvert 05.12.13 at 9:58 pm

@ JW Mason 38:

â€œThere is no reason we canâ€™t bring technological progress to a halt and establish a society that could be sustained on earth indefinitelyâ€¦.We can finally organize society around the development of our capacities as human beings, instead of endless accumulation of stuff.â€

What could be a more significant â€œdevelopment of our capacities as human beingsâ€ than to people the stars and rouse dead worlds with lifeâ€™s infinite inventiveness?

Does your concept of â€œdevelopmentâ€ amount in the end to anything more than the comfort of a tenured ape basking under a familiar sun, relieved that all expansive, dynamic impulses have been stamped out so that no one can hurl asteroids at him? Is that the sterile endpoint of all human aspiration? Have you no soul left to be stirred?

Letâ€™s accumulate more stuff and technology, endlesslyâ€”and more planets, more experiences, more epics of discovery and settlement. Letâ€™s indeed follow the logic of Darwinism, the oldest commandment of Nature, and of Natureâ€™s Godâ€”to be fruitful and multiply, and spread to the farthest reaches of the universe.

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Jerry Vinokurov 05.12.13 at 10:03 pm

We have actual problems that we might like to solve on earth before we think about expanding to the stars For Great Glory. It’s called “prioritizing,” you might want to look into it.

57

John Quiggin 05.12.13 at 10:06 pm

@fivegreenleafs The comparison between progress in computing technology and virtual stasis in transport technology is one of the reasons I’ve come to the view that interstellar space travel is impossible.

To extend your comparison a bit, at the time of the Apollo landing, the state of the art computer was the IBM 360, which ran at about 0.03 MIPS and had 10Mb hard disk modules. The state of the art in air transport was the Boeing 747, and the land-speed record for wheeled vehicles had been set at just over 400 mph. Need I say more?

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Jerry Vinokurov 05.12.13 at 10:13 pm

To extend your comparison a bit, at the time of the Apollo landing, the state of the art computer was the IBM 360, which ran at about 0.03 MIPS and had 10Mb hard disk modules. The state of the art in air transport was the Boeing 747, and the land-speed record for wheeled vehicles had been set at just over 400 mph. Need I say more?

This assumes that different technologies scale in the same way. I don’t know why you would assume that. To examine the air transport issue, there’s a very obvious barrier to higher speed air transport: the Mach barrier. Also, things like nonlinear scaling of drag with velocity in general. The problems of interstellar travel, such as they are, are completely different in nature. It may or may not turn out to be possible to travel between the stars, but we won’t learn anything about whether it is or not from looking at earth-based air transport.

59

maidhc 05.12.13 at 10:17 pm

Since mushroom spores are already capable of space travel without being enclosed in a space ship, perhaps it would be more cost-effective to genetically engineer a race of intelligent mushrooms.

60

But it also seems to me that itâ€™s perfectly possible to halt the process before then. If we get rid of capitalism and the state â€” the two main locuses of competition â€” there is no reason we canâ€™t bring technological progress to a halt and establish a society that could be sustained on earth indefinitely. I presume this has happened to intelligences elsewhere. The condition of survival on one planet is to rein in the forces of competition, expansion and conflict. Which is good â€“ it means we can finally organize society around the development of our capacities as human beings, instead of endless accumulation of stuff.

I read this two or three times scratching my head and wondering what it could mean, before I finally realized Mason equates “technological progress” with “endless accumulation of stuff” and not with “development of our capacities as human beings.” It’s clear enough in the text, but is such a strange view to me it took a while to assimilate. Now I know who these people are that say Kubrick’s 2001 is a boring movie – they are drawn from those who wouldn’t disturb the universe, and whose fondest, most forlorn, grandest hopes for humanity involve nothing more than “sustainability” and living in peaceful harmony with nature.

61

Walt 05.12.13 at 11:04 pm

Will, that is the least attractive vision of the purpose of human life that I have ever heard. Being a Shaker or Wahhabi Islam both sound preferable.

62

John Quiggin 05.12.13 at 11:05 pm

” It may or may not turn out to be possible to travel between the stars, but we wonâ€™t learn anything about whether it is or not from looking at earth-based air transport.”

But it was the spectacular progress in earth-based air transport from 1900 to 1960, including the breaking of the sound barrier, that led people to assume that something similar was possible in space travel. In particular, lots of people assumed that we would find a way to break the light barrier, and therefore that distances of 10 or 100 light years wouldn’t be a problem. The fact that the speed of light is an absolute limit, and not a tech problem wasn’t widely understood.

63

Jerry Vinokurov 05.12.13 at 11:35 pm

But it was the spectacular progress in earth-based air transport from 1900 to 1960, including the breaking of the sound barrier, that led people to assume that something similar was possible in space travel. In particular, lots of people assumed that we would find a way to break the light barrier, and therefore that distances of 10 or 100 light years wouldnâ€™t be a problem. The fact that the speed of light is an absolute limit, and not a tech problem wasnâ€™t widely understood.

I don’t understand what this is supposed to demonstrate. Comparing light to sound may be a popular misunderstanding that gave lots of people reason to say all sorts of silly things, but it’s neither here nor there. Those people were just as wrong as people who are extrapolating air travel from 1960 to the present day into the future; my point wasn’t that those extrapolating the period from 1900 to 1960 into the future were right, but that we have no reason to extrapolate from one domain of technological discovery to another without actually understanding those domains.

There are things we know are never going to be possible. Perpetual motion is one. Traveling faster than light, in a conventional sense (i.e. absent any kind of esoteric wormhole physics, just by having better engines) is another. I have no idea whether future discoveries may make it possible to circumvent the light barrier in a different way (I’m not optimistic about that, but that’s just a gut feeling) or perhaps sufficiently advanced technology may make thousand-year-long trips across interstellar distances more possible. I’m just saying that we won’t know the answers to these questions on the basis of anything that’s come before, because they are qualitatively different questions.

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Rich Puchalsky 05.12.13 at 11:37 pm

Will B: “Letâ€™s accumulate more stuff and technology, endlesslyâ€”and more planets, more experiences, more epics of discovery and settlement. Letâ€™s indeed follow the logic of Darwinism, the oldest commandment of Nature, and of Natureâ€™s Godâ€”to be fruitful and multiply, and spread to the farthest reaches of the universe.”

It’s always hard to know when something is a Poe or not.

Naturally, I believe that the universe has already been taken over by an advanced species that just so happens to hold exactly *my* civilizational, cultural, and personal preconceptions. So they laugh just as hard as I do when some alien life form goes on about how they have to settle other planets because of Nature’s God.

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Lee A. Arnold 05.12.13 at 11:38 pm

There is no reason we canâ€™t bring technological progress to a halt and establish a society that could be sustained on earth indefinitely. And live in peaceful harmony with nature. On the other hand, there is no reason why we cannot continue technological progress, and establish a society that could be sustained on earth indefinitely, and live in peaceful harmony with nature.

How many times do we have to have this argument? The problem is not technology. The problem is a FORM OF THINKING that is necessary to cognition and to material wealth-getting. The form of thinking is the “splitting-and-comparing” function, what Hobbes called “ratiocination” (or at least, I think that is his meaning for the term). Of course it helps you get through your day, it is the basis of mathematics and science, and it is the method of economics.

Ratiocination is necessary and fun, and it leads to more discoveries. But 1) ratiocination cannot be used to precisely predict whole systems like the climate or a wildlife food web. They remain precisely unpredictable. Ratiocination 2) snips a lineal segment out of a larger circular chain: so, we didn’t expand our awareness of where our pollution was going in the environment, until the effects became harmful and apparent. 3) Technology is ratiocination, made into a material, instrumental extension, or so Heidegger might have said. In this guise it can be frequently and blindly applied without limit — or until an outside limit crashes the whole system.

The blindness incurred by ratiocination, sometimes called technological hubris, was a long episode in the history of scientific modernism. We see the problem now, and we are getting over it, but we haven’t mastered it quite yet.

This sort of confusion however is WHY the aliens aren’t decelerating to nonrelativistic matter in this neighborhood. So you will have to look into the light.

66

ChrisB 05.12.13 at 11:47 pm

Why do people obsess about interstellar colonisation? Because they don’t want to die, and they believe that dying as a civilisation or as a species is analogous to dying as a person, the person being them; which it really isn’t.
Our civilisation and our species are going to die, either at the heat death of the universe or before, and if ultimate extinction is going to make our civilisation meaningless it’s meaningless now. Alternatively, a civilisation that isn’t meaningful unless it’s infinitely extended is a pretty poor guide to making moral distinctions today.
(a) that I’m astounded that nobody has linked to the much more technical exploration of the practical issues of space colonisation by Charlie Stross over at http://www.antipope.org/charlie/blog-static/2007/06/the-high-frontier-redux.html
and
(b) I’m mildly surprised that nobody really seems to believe in evolution. Whatever reaches the stars in a thousand million years, it’ll resemble us as little as we resemble our ancestors of that vintage, which is to say hardly at all. See Alan Coren’s discussion of the issue at http://livetoad.blogspot.com.au/2009/12/somebody-up-there-like-me.html

67

Jerry Vinokurov 05.12.13 at 11:53 pm

But 1) ratiocination cannot be used to precisely predict whole systems like the climate or a wildlife food web. They remain precisely unpredictable.

This really isn’t as profound as it sounds, because nothing can be used to “precisely predict whole systems,” in this way. This is a well-known phenomenon: chaotic environments make individual trajectories incalculable in principle. But this is also not actually a problem for the majority of the things we’re interested in calculating, because we’re not in the business of predicting individual trajectories but large-scale systemic changes. And actually, ratiocination (as you define it) can be used to make those predictions; indeed, has been making those predictions and getting them right for quite some time now, especially with regards to climate.

Of course we should be on guard against technological hubris. But that’s not an excuse to let this kind of sloppy criticism prevail. If you want to know the answer to what the planet will look like with an additional 3 degrees of warming, your best bet is ratiocination (or “science,” as I like to call it).

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Omega Centauri 05.12.13 at 11:58 pm

Chris B, yes, I too find that worrying about our progeny who are multiple evolutionary timespans down the winds of time rather irrational. If we could be magically time transported to meet them, but couldn’t even recognize them as the same species -or understand them, would we care about their future prospects?
We forget the major explosion of multicellular complexity took a hundred million years or less. And that stuff looks really really alien to us.

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Eric Drexler 05.13.13 at 12:07 am

â€œThe fact that the speed of light is an absolute limit, and not a tech problem wasnâ€™t widely understood.â€

Indeed. And physics determines not only upper bounds on the physical potential of technology, but lower bounds as well. This, too, isnâ€™t widely understood.

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David 05.13.13 at 12:08 am

“If we could be magically time transported to meet them, but couldnâ€™t even recognize them as the same species -or understand them, would we care about their future prospects?”

Nothing sentient is alien to me.

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Matt Austern 05.13.13 at 12:45 am

People are being awfully optimistic in talking about the speed of light as an absolute limit. Voyager 1 is travelling at 62,000 km/h, or 17260 m/s, or a little less than 0.00006c. So we’re more than two orders of magnitude away from getting to 1% c â€“ and that’s a 700kg probe, not a hundred-thousand-ton starship with a crew of thousands.

I can’t think of any plausible propulsion technology that we could use to accelerate a large starship to anywhere near the speed of light. (Not even if you count nuclear fusion as plausible technology.) As far as our ability to build rockets is concerned, the limits imposed by special relativity hardly matter. Relativistic effects don’t start becoming really important until around 0.7c, and that sort of speed is pretty unrealistic.

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Eric Drexler 05.13.13 at 12:49 am

A bit of physics-based comparative arithmetic for interstellar travel:

The energy required to boost a ton to a moderately relativistic velocity (kinetic energy = rest mass, ~100 exajoules) is nearly one billion times the energy required to boost a ton to the Moon. The total current human power consumption (~15 terawatts, if one includes burning dung for cooking) would suffice to boost 0.17 milligrams per second, if the energy could be applied efficiently.

A civilization contemplating fast interstellar travel would need to have somewhat greater resources at its disposal.

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floopmeister 05.13.13 at 12:58 am

Is that the sterile endpoint of all human aspiration? Have you no soul left to be stirred?… Letâ€™s accumulate more stuff and technology, endlesslyâ€”and more planets, more experiences, more epics of discovery and settlement. Letâ€™s indeed follow the logic of Darwinism, the oldest commandment of Nature, and of Natureâ€™s Godâ€”to be fruitful and multiply, and spread to the farthest reaches of the universe.

Sure I have a soul to be stirred – just not by that view of human existence.

However I’m sure bacteria would find it riveting – dreaming of life beyond the outer reaches of their petri dish.

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blavag 05.13.13 at 1:05 am

On interstellar travel see NASA on the Alcubierre Drive;
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110015936_2011016932.pdf

On economists writing about it see:
http://www.princeton.edu/~pkrugman/interstellar.pdf

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Brett 05.13.13 at 1:10 am

@Matt Austern

I canâ€™t think of any plausible propulsion technology that we could use to accelerate a large starship to anywhere near the speed of light. (Not even if you count nuclear fusion as plausible technology.) As far as our ability to build rockets is concerned, the limits imposed by special relativity hardly matter. Relativistic effects donâ€™t start becoming really important until around 0.7c, and that sort of speed is pretty unrealistic.

I could imagine some type of externally powered laser propulsion system getting there, since it would probably be easier to front-load the energy requirements of acceleration than actually carry such a power supply on board a ship (never mind figuring out a type of rocket that could actually turn it into useful work). God knows how you’d slow it down, though – you’d probably have to send a much slower ship in advance to build a laser set-up at the destination, which takes you back to the same problem.

Other than that, there’s not much. The only ship we have that doesn’t rely wholly on speculative technology is Project Orion, and a speed of 3-5% of the speed of light means that you don’t get to even Alpha Centauri short of 86-143 years.

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Lee A. Arnold 05.13.13 at 1:14 am

Jerry Vinokurov #67: “This really isnâ€™t as profound as it sounds, because nothing can be used to ‘precisely predict whole systems,’ in this way.”

You manage to miss the point. Yes of course ratiocination is all we have for prediction and control. And you miss, as well, other reasons it fails in complex systems: It is also a well-known phenomenon that n-body computation is intractable for precise prediction. This is a different phenomenon from chaos, and (I would argue) it applies independently to the problem of prediction for any complex system that is modeled as some sort of n-compartment system, which is all of them.

But more important, this problem of precise non-prediction is indeed a very big problem for one of the things we are interested in treating, a couple of things actually, not only climate but species extinction. Why? Because in this situation, all that scientists do is point to statistical aggregates of results. You know that 3 degrees is coming, more or less, in a century, more or less — but golly, it turns out that isn’t good enough, yet. Because these are very big policy questions, questions that go outside of science, and your lack of precision is not counteracting an enormous inroad into contrarianism and confusion by vested interests who will lose money if things don’t go their way. So it’s “not your fault”.

Well guess what? We have arrived at an alternative definition of “ratiocinative/technological hubris” that would be hard to improve upon: Scientists who think that what they can do, is all that they NEED to do. This is exactly the sort of sloppy policy logic that economists fall back on too. But in a complex system that cannot be precisely predicted, you are never only a scientist.

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Lee A. Arnold 05.13.13 at 1:17 am

Actually it isn’t a different phenomenon from chaos, it is the condition from which the science of chaos first arose.

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Eric Drexler 05.13.13 at 1:19 am

Since weâ€™re being quantitative here…

At the velocity mentioned above (~0.87 c), time dilation is only a factor of 2 (alleviating 50 years of ship-time boredom per century of flight), while typical interstellar gas looks like a relativistic particle beam with a power density of 100 kilowatts per square meter. On impact, interstellar dust grains deliver about 1000 times as much energy per unit mass as a thermonuclear bomb. Shielding a fast vehicle becomes an interesting engineering problem, even for an automated probe.

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Eric Drexler 05.13.13 at 1:34 am

@blavag â€” NASA aside, all one really needs to know about the â€œAlcubierre warp driveâ€ is that anything moving faster than light, whether wrapped in warpiness or not, violates causality (i.e., is equivalent to a time machine).

@Brett â€” The most credible schemes do use laser propulsion, as you suggest, but they apply light pressure directly rather than using light to power rockets. The propulsion efficiency of light pressure approaches 1 as speeds approach c.
————–
This is a fun topic, but the implications of mechanical scaling laws for manufacturing throughput and considerations involving thermal fluctuations in small mechanical systems have rather more practical consequences for the world situation.

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gordon 05.13.13 at 1:34 am

“On behalf of my fellow Australians, Iâ€™m going to make a counter-offer…”

I’m not quite sure whether Prof. Q. is being ironical here. Is this a reference to the possibility of rehabilitating and resettling large areas of Earth currently deserted? I’m sure that is possible, with careful attention to water- and land-management practices, recycling and conservation in general, and I guess it would indeed amount to a much more practical alternative to interstellar/interplanetary colonisation.

But then the irony (if it is irony) gets deeper when you consider that there may be some people (though thinly scattered) who actually think such places belong to them. Is Prof. Q. making a sly reference to the problem of interstellar colonists finding and displacing primitive aliens with their (the colonists, that is) superior technology? Is this a reference to what happened during the Age of Discovery here on Earth, when lots of relatively primitive people (on the Guns, Germs and Steel scale, anyway) were dominated and/or displaced and/or slaughtered and/or infected by Europeans?

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floopmeister 05.13.13 at 2:11 am

Is this a reference to what happened during the Age of Discovery here on Earth, when lots of relatively primitive people (on the Guns, Germs and Steel scale, anyway) were dominated and/or displaced and/or slaughtered and/or infected by Europeans?

In which case the reference to Australia is more than apt.

In terms of real/actual ‘Terra Nullius’ the last uninhabited piece of real estate colonised by humans was Iceland. Every colonisation since then has involved muscling aside those already there.

Actually Iceland is a fascinating example of human society formation in the context of a ‘tabula rasa’ – the dispute resolution and governance models of early Free State Iceland would be interesting in terms of the social and political organisation implications of the colonisation of another world.

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Matt 05.13.13 at 2:37 am

Apollo spending peaked at \$6.7 billion in 1966, while GDP of the USA was \$780 billion — both figures nominal. In that year primary energy consumption of the USA was 55 exajoules*. Let’s pretend that energy expenditure is proportional to dollar expenditure. That would mean Apollo energy expenditure peaked at 470 petajoules in 1966. Let’s scale that up by a factor of 300 trillion for the interstellar job, and convert to watts:

(470 * 10^15 * 300 * 10 ^ 12) / (365 * 24 * 60 * 60) = 4.47 * 10^24 watts. Or about 1 percent of the total energy output of the sun. I wouldn’t immediately dismiss the premise in fiction, but that’s about the best I can say of it. Clearly passenger-bearing interstellar travel awaits some combination of improved passengers, destinations nearer than 1200 light years, and industrial production uncoupled from human labor.

*Originally given in Statistical Abstracts of the United States as 51864 trillion BTU — what an ugly unit. One exajoule is about 1.05 quadrillion BTU.

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pjm 05.13.13 at 3:03 am

Subjective travel time can be reduce to essentially zero via time dilation (after the initial acceleration, which at 1 G takes on the order of year). I believe the kinectic energy scales up in proprortion to the time dilation factor, so time dilation of factor 10 requires in kinectic energy on the order of 10 times the resting mass (which is already a huge amount of energy, remember mc squared).

Charlie Stross’ discussion of solar system colonization is surprisingly shallow (though he gets lots right), he doesn’t actually seem to have appreciated Gerald O’Neil contributions (someone who is not at all a quantitative slouch). But, in agreement with his basic point, solar system expansion will only be economical from the moon, i.e., potential colonists will have to be born and raised there, feed off of locally grown food stocks.

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Matt 05.13.13 at 3:36 am

Charlie Strossâ€™ discussion of solar system colonization is surprisingly shallow (though he gets lots right), he doesnâ€™t actually seem to have appreciated Gerald Oâ€™Neil contributions (someone who is not at all a quantitative slouch). But, in agreement with his basic point, solar system expansion will only be economical from the moon, i.e., potential colonists will have to be born and raised there, feed off of locally grown food stocks.

O’Neill, Zubrin, and many other space colonization enthusiasts have tried to find material incentives for colonization. The numbers just don’t work with present or easily foreseeable technology. The political economy of very large space projects dooms any project too grand in its sweep. The projects that can be done incrementally, and maybe eventually turn a profit, are likely to be automated to the hilt and no stepping-stone for colonies.

O’Neill envisioned zero gravity and advanced automation enabling super-productive orbiting factory workers that could quickly pay off their expensive infrastructure. I think he probably had it backwards. There’s not much economic advantage to zero gravity manufacturing, advanced automation will arrive first on Earth where you don’t need radiation-hardened electronics, and if people inhabit space they will do so because they first became comfortably rich on Earth and were looking for some adventure to spice up their lives. The SF story of fleeing Earth for a better economic life in the space colonies — patterned after migration in the age of sail — doesn’t make sense when you look at what Earth has and what space has. It’s like migrating to Haiti to escape the economic problems of Michigan.

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Matt Austern 05.13.13 at 3:38 am

And that gets to the question of what propulsion system you have in mind that lets you accelerate at 1g for a year. If you’ve got a hundred-thousand-ton starship then indeed it’s frightening to think about the kinetic energy required to get Î³=10 (I make it 10^26 J; call it a billion gigawatts for a year), but that’s actually the optimistic number, because that assumes all the energy you expend goes directly into your payload’s kinetic energy. If there’s any inefficiency in your propulsion system, or if your ship carries fuel that has to be accelerated too, or if you plan to slow down when you get to your destination, then the numbers get truly insane.

You should not assume that ultra-relativistic human spaceflight will ever be possible.

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Lawrence Stuart 05.13.13 at 3:42 am

@ J W Mason: What the hell does ‘the logic of darwinism’ (by which I assume is meant natural selection) have to do with a self consciously teleological species, like us?

And nice job channelling the spirit of Hesiod. Which of course calls forth Homer @ 55.

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Omega Centauri 05.13.13 at 3:49 am

In the case of interstellar settlement, the odds of fiding a sentient species to displace are pretty small (at least per earthlike planet). If say we doscovered a continent with the highest intelligence being only slightly smarter than chimpanzees, would we feel remorse displacing them? Should we?

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Jerry Vinokurov 05.13.13 at 4:06 am

You manage to miss the point. Yes of course ratiocination is all we have for prediction and control. And you miss, as well, other reasons it fails in complex systems: It is also a well-known phenomenon that n-body computation is intractable for precise prediction. This is a different phenomenon from chaos, and (I would argue) it applies independently to the problem of prediction for any complex system that is modeled as some sort of n-compartment system, which is all of them.

Many-body problems are intractable for the same reason that chaotic systems are intractable: because they are coupled systems of nonlinear differential equation. Take away whatever the “body” is and just look at the math; the formalism is the same. Many-body systems are not necessarily chaotic, but they can exhibit chaos, which is just sensitivity of trajectories to initial conditions. They can also be stable (e.g. the solar system). None of this is really “different” because what drives the unpredictability is the way the differential equations are coupled to each other.

But more important, this problem of precise non-prediction is indeed a very big problem for one of the things we are interested in treating, a couple of things actually, not only climate but species extinction. Why? Because in this situation, all that scientists do is point to statistical aggregates of results. You know that 3 degrees is coming, more or less, in a century, more or less â€” but golly, it turns out that isnâ€™t good enough, yet. Because these are very big policy questions, questions that go outside of science, and your lack of precision is not counteracting an enormous inroad into contrarianism and confusion by vested interests who will lose money if things donâ€™t go their way. So itâ€™s â€œnot your faultâ€.

I don’t understand why you are using the words “statistical aggregated results” as a pejorative. What else should they be looking at? Why is it not enough to know that 3 degrees are coming over the next 100 years, coupled with what we do know about the way local environments respond to global climate change?

You mention contrarians, but I don’t understand the point. Contrarians aren’t people who are interested in being convinced by the facts, so this discussion is useless insofar as it concerns them. Your right-wing uncle is going to tell the same “if the globe is warming how come it’s cold in January” “joke” that he tells every year; the precision or lack thereof of global climate models is hardly the point here. Yes, global climate change is a big policy question, I would say the biggest of our time, but that has zero to do with any point about “precision” or whatever. The science is good enough to forecast what it needs to forecast, and has been for some time; we can improve the reliability of the forecast by collecting better data, or using better methods, but ultimately it’s all “statistical aggregation” anyway. If your point is that it doesn’t have the argumentative force that an “exact” prediction would have, then sure, I agree, but we’ve already established that exact predictions are not available anyway.

Well guess what? We have arrived at an alternative definition of â€œratiocinative/technological hubrisâ€ that would be hard to improve upon: Scientists who think that what they can do, is all that they NEED to do. This is exactly the sort of sloppy policy logic that economists fall back on too. But in a complex system that cannot be precisely predicted, you are never only a scientist.

Who are these mysterious scientists who think this? Indeed, I am not only a scientist, but I wasn’t ever arguing that scientists shouldn’t be part of policy debates or that it’s sufficient to live one’s life hermetically sealed in a lab. I was just responding to a point you made, in the context of talking about actual scientific work, which struck me as bizarre and totally inaccurate. If you want to talk about how scientists should participate in policy debates, I’d love to have that discussion, but it wasn’t the one I thought was going on here.

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JW Mason 05.13.13 at 4:46 am

Will B.-

Ok, my comment about bringing about bringing technological progress to a halt was a bit of trolling. I’m quite sure interstellar travel will never be possible, but I am a fan of science.

As for what constitutes the good life, well, we won’t be able to resolve that in this comments thread. I might try to put together a statement of my point of view on the Slack Wire at some point, in which case you’ll be free to post a rebuttal.

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Lee A. Arnold 05.13.13 at 5:00 am

Of course it is about policy input. I didn’t write pejoratively about scientific work, I pointed out that it cannot make a precise prediction in certain situations, and this sometimes has dramatic consequences. There is a formal limitation in our method of thought that has caused environmental problems in the past (and I think that is where the misplaced distrust of technology comes from, which is what my original comment was about). And now the very same limitation, because it gives imprecise results, is not convincing enough people to adopt a proper climate policy. So to answer your question, it is obviously NOT enough to know that 3 degrees are coming over the next 100 years, or else the policy would be changed by now.

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John Quiggin 05.13.13 at 5:01 am

@Gordon As someone on my Twitter feed intuited, I had in mind such brilliant ideas as the Multi Function Polis, which mixed the themes you mention.

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fivegreenleafs 05.13.13 at 5:03 am

@John Quiggin said, “To extend your comparison a bit … The state of the art in air transport was the Boeing 747, and the land-speed record for wheeled vehicles had been set at just over 400 mph. Need I say more?”

To your question, I would say, yes,

Two things,

First, one reason I took the example of the mapping of the human genome was, that from the perspective of a scientist in the field 1990, the project was truly on the borders of science fiction, and if you in all seriousness had proposed that in 20 years time, you would be able to sequence a whole human genome in a day, he/she would probably give you a frozen smile, while discreetly calling 911.

The reason this changed (in such a dramatic fashion), was both due to improvements in existing technology beyond anything anyone then could (or did) foresee, and, completely new technologies no one had even dreamt about.

In regard to the expansion in raw computer power, this is “only” a quite well known continuation of a progress that started about 60 years ago, but, that in its nature is highly non linear.

I would say that as humans, we are equally inept in handling both these aspects of technological change, i.e. the unknown and the non linear.

Second, time frames. If you view human travelling, not from an arbitrary time point taken 1969, but spanning the last 10 000 years, you will find that it did not change in a constant linear fashion, but very much in short dramatic fits and starts. When viewed since the mid 19th century, it has changed very much indeed, and I do not think that “journey” has stopped, but we do probably have to wait a while for other technological developments to make it possible (or rather) economically feasible to take the next big leap…

Looking in the hindsight mirror, I would say a lot of humility is in order; we simply do not know, and can often not even begin to predict. What we should know, from our past experience, is to expect the impossible to become reality.

Side note, I was curious whether your op was truly serious, but I find these aspects of human nature, thinking and perception, truly fascinating and important.

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Hector_St_Clare 05.13.13 at 5:09 am

Re: Yes. Probably also written by a Theologian before Columbusâ€™ expedition. (Setting aside for the moment the Eurocentric bias).

Um, given the demographic collapse that hit the Americas after Colombus’ voyage, I’m not at all sure that those ‘Theologians’ weren’t right.

Some kind of contact was going to happen eventually, of course (and some contacts had happened before Colombus, for that matter), but if they’d happened a few centuries later the demographic collapse might have been averted.

Re: I really truly think the difficulty of â€œgestating, birthing and raising
humanlike animals, is small potatoes compared to actually getting there. I.e.
if we could solve the issues of getting there, we could solve the issue
of having the spacecraft regenerate from a database of genetic information

I really think that’s extremely unlikely. Living systems are extremely complicated. I don’t want to say impossible, but I strongly doubt it will ever happen.

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Lee A. Arnold 05.13.13 at 5:41 am

Do they have to be nonlinear differential equations? I would think that any compartmental system is indeterminate (unless the equations are simultaneous) because the final result would depend on where you start the calculations. I can think of a tiny, nondifferential, linear system that is completely indeterminate: “4 x 8 – 1”. The two results are “31” and “28”. Chaos! Arithmetic introduced parentheses to avoid chaos: (4 x 8) -1. They look like two little crutches, to prop-up ratiocination at its very beginnings.

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Jerry Vinokurov 05.13.13 at 5:44 am

Of course it is about policy input. I didnâ€™t write pejoratively about scientific work, I pointed out that it cannot make a precise prediction in certain situations, and this sometimes has dramatic consequences. There is a formal limitation in our method of thought that has caused environmental problems in the past (and I think that is where the misplaced distrust of technology comes from, which is what my original comment was about). And now the very same limitation, because it gives imprecise results, is not convincing enough people to adopt a proper climate policy. So to answer your question, it is obviously NOT enough to know that 3 degrees are coming over the next 100 years, or else the policy would be changed by now.

This is a strange chain of causality. The inability to make precise predictions is not, I think, what’s driving the policy problems. Maybe you have some evidence that this is the case, but I seriously doubt that if the method were somehow better and the predictions more precise we’d get better policy. The cause of environmental problems is not a “formal limitation in our method of thought;” you don’t need to be even a scientist to suspect that dumping sludge in a river is not a good plan, but in any case, the science on dumping sludge in rivers is solid and has been well-known for a long time. Somehow, this did not prevent sludge from being dumped in rivers.

Knowing the gross details of how climate change is going to play out is enough, actually. Your counterfactual hypothesis ignores the other thing you said before, which is that there are powerful, entrenched forces that profit from the status quo. It doesn’t matter that we can’t somehow pin down the trajectory of weather in a single city; we know pretty damn well what kind of consequences to expect, and the people who refuse to acknowledge those consequences are being either deliberately obtuse or downright evil. Even if one could deliver the impossible unicorn you desire, it would not satisfy them; they would just demand we wait for more data, better data, whatever. They are not participants in a scientific debate, they are professional obfuscators and shills, and as such it wouldn’t make one bit of difference to them what the evidence actually says.

This isn’t about the limitations of science as a formal method at all. This is very much about the political problems of implementing policies to mitigate those predictions. It’s got nothing whatsoever to do with the forecasting accuracy of climate models.

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bad Jim 05.13.13 at 6:13 am

Vonnegut had a good idea in The Sirens of Titan, a robot sent as a messenger from a distant planet. It’s a slow way to transmit information (although the bandwidth of physically shipping media in bulk is still pretty good) but a quick way to carry on a conversation, since the interval between question and reply is no longer constrained by distance.

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Zamfir 05.13.13 at 6:24 am

As addition to Matt Austern above: inefficiencies in the system are not just a problem because they raise the required energy. They are even more basically a cooling problem.

If the drive converts energy to kinetic energy at 99% efficiency, or 99.99%, the remainder would still vapourize a 100,000 ton ship instantly. That energy flow would have to be dumped to space (comparable to the cooling of the entire sun-lit earth), without ever going through the mass of the ship in any way. Just the heat flux would be instantly destructive to any material.

Such a drive would have to be immaterial, in the literal sense of the word. Capable of imparting perfectly directed momentum to mass of the ship, while its main parts would have to something else, generated fields or so that can withstand more abuse than the puny fields that hold solid matter together.

So yeah,getting there is really hard, even compared to machinery that could build and raise a human from scratch. And not because the latter is simple.

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Mercy 05.13.13 at 9:03 am

I’m not entirely sure if @12 is joking about colonising space to escape climate change, but it’s a sentiment I’ve seen before from otherwise intelligent people and I think it reveals the muddled thinking underlying a lot of space colonisation talk.

It’s not just that the technology to survive indefinetely in space is far or terraform an earth like planet less demanding than the technology to produce self sustaining colonies anywhere on earth or make the entire planet hospitable to life. It’s that it’s a considerably less advanced version of the same technology. By the time we could survive off earth there is nothing we could do to it to make it uninhabitable.

Moreover as J. Quiggan points out the technology to make Antarctica habitable is orders of magnitude less advanced than the technology to survive indefinitely in outer space. The same goes for the surface of the oceans and much of our orbit. We aren’t going to run out of space any time soon, what we lack is the resources to make that space habitable. Which, incidentally, another planet doesn’t get you any closer to than interstellar space: terraforming mars, or carpeting it in dome cities, is almost certainly more difficult/expensive than building an equivalent amount of just as nice orbiting habitat.

Of course the flipside of this is that colonisation and “ships” is the wrong framing, what we are talking about is building self sustaining habitats that can survive in space. After that, where to put them is a minor question, but “at the bottom of a gravity well” is rarely going to be the right answer. If they feel like visiting Alpha Centuri, the generations aboard during the “journey” won’t be particularly disadvantaged compared to the ones at the destination.

The other important point is that the technology we need to colonise space isn’t physics or mechanical engineering, it’s ecology, agricultural science, closed loop resource management. Our current locomotive technology is enough to put us in reach of enough space to do us for a very long time. What we lack is the ability to survive without extracting resources from existing ecosystems – what we need is the ability to create closed loop, sustainable habitats, to get our resource needs down to stuff that can be had in an asteroid belt. Which is also what we need to not drive ourselves extinct on earth, making most of the conflict between space cadets and hippies unnecessary.

In other words, we don’t need to go to Kepler-62 to escape climate change, but if we can’t deal with climate change we can’t get to Kepler-62, not in a spiritual or political sense but quite literally technologically: all the environmental problems we deal with on earth are a small preview of the problems facing us off it.

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Brett 05.13.13 at 9:38 am

@Eric Drexler

@Brett â€” The most credible schemes do use laser propulsion, as you suggest, but they apply light pressure directly rather than using light to power rockets. The propulsion efficiency of light pressure approaches 1 as speeds approach c.

That’s what I meant, I think. You build some massive lasers at home and “push” on a “sail” to accelerate your ship. God only knows how powerful they’d have to be, but I suspect it would be easier to have them at home instead of having to send them on the ship.

This is a fun topic, but the implications of mechanical scaling laws for manufacturing throughput and considerations involving thermal fluctuations in small mechanical systems have rather more practical consequences for the world situation.

Was that a nanotechnology reference?

@matt

Agreed. I tend to think that if we get space colonization at all, it will be either under some different political conditions (like some revival of “space nationalism”), or because a group of people rich by modern comparison have access to the necessary resources and really want to do it. In the latter’s case, they’d be like a religious colony, or perhaps a monastery expansion into the “wilderness” 11th century CE style. They could even be some type of scientific outpost with an increasingly large host of permanent residents (due to the cost of transit).

It won’t be for anything similar to what helped drive further European colonization and conquest in the Americas: the space equivalent of gold, silver, slaves, and 1000% mark-up tobacco.

@Omega Centauri

If say we doscovered a continent with the highest intelligence being only slightly smarter than chimpanzees, would we feel remorse displacing them? Should we?

I would. Why would you do that, when you can build habitats far more habitable than any alien planet? Unless we’re trapped in some type of Deepness in the Sky cycle of triumph and societal collapse.

@Hector St Clare

Some kind of contact was going to happen eventually, of course (and some contacts had happened before Colombus, for that matter), but if theyâ€™d happened a few centuries later the demographic collapse might have been averted.

Or if there had been more of a delay between contact and conquest, like if the European diseases had made it over to ravage the Amerindian population, but they had enough time for those resistant to recover and replenish before colonists showed up. Without a Mexica population ravaged by disease, it’s doubtful that Cortez and his native allies would have been able to take the empire.*

* Not that I’m weeping over the death of the Mexica Empire, considering its brutality and human sacrifices.

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ajay 05.13.13 at 9:45 am

Once again we are hearing assertions from the ill-informed that human life is possible in Australia. But this is sheer nonsense.

Let’s talk about travel costs first. When I take a taxi home from work, a distance of some 5 miles, it costs at least Â£12 and often more like Â£15. Roughly Â£3 per person per mile, then. Australia is some 25,000 miles away from London.
Now, these “Australians” claim that the population of their “country” is around 23 million. To transport all these people the 10,500 miles to Australia – by taxi – would therefore cost Â£724 billion.

This is more than half the total GDP of the United Kingdom even today! It’s ridiculous to suppose that in the past – when the UK economy was much smaller – it should have embarked on such an economically crippling effort in order to establish a remote and largely irrelevant settlement on the other side of the world.

Therefore, Australia cannot possibly exist.

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ajay 05.13.13 at 9:47 am

Sorry, 10,500 miles. But the maths still works.

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gordon 05.13.13 at 9:47 am

In case anybody is interested, here’s a link to the Wikipedia article on the Multifunction Polis mentioned by Prof. Quiggin at 91:

http://en.wikipedia.org/wiki/Multifunction_Polis

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ajay 05.13.13 at 9:50 am

In terms of real/actual â€˜Terra Nulliusâ€™ the last uninhabited piece of real estate colonised by humans was Iceland. Every colonisation since then has involved muscling aside those already there.

The Maoris arrived in New Zealand later than that. Iceland was settled in 870, New Zealand in around 1300.

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Salient 05.13.13 at 10:46 am

Maybe optimists (?) can safely (?) assume that we haven’t been colonized because by the time all these starhopping alien civilizations achieve the capability of surviving indefinitely-long interstellar travel, colonizing a planet’s just not worth the effort. They’d probably spend more time mining plutonium or whatever the hell else they’re in need of, and AFAIK we don’t have any reason to believe that our planet is unusually plutonium-rich.

Alternatively, accepting the conclusion that all human life will end eventually, and that subduction will completely obliterate any evidence of our existence long before the Sun novas, actually implies that humanism is all the more important, imperative, immediate. If there’s only finitely many people we can’t justify reassuring ourselves with the prospect of an indefinitely sustainable future society doing the work for us — there’s only finitely many people ever, meaning the particular experiences of the ones alive now matter a lot more than they might under an infinite system.

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ajay 05.13.13 at 10:50 am

AFAIK we donâ€™t have any reason to believe that our planet is unusually plutonium-rich.

No indeed, since plutonium does not exist in nature. It’s an entirely artificial element.

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Mao Cheng Ji 05.13.13 at 10:55 am

“Letâ€™s indeed follow the logic of Darwinism, the oldest commandment of Nature, and of Natureâ€™s Godâ€”to be fruitful and multiply, and spread to the farthest reaches of the universe.”

Yes, God wants you to be fruitful and multiply, but the logic of Darwinism, doesn’t it dictate you, for this purpose, to mutate into something that can easily survive in space and move very fast?

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ajay 05.13.13 at 10:55 am

So, actually, our planet is extremely unusually plutonium-rich, in that it has a non-zero amount of plutonium in it.

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ajay 05.13.13 at 10:56 am

the logic of Darwinism, doesnâ€™t it dictate you, for this purpose, to mutate into something that can easily survive in space and move very fast?

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Mao Cheng Ji 05.13.13 at 11:00 am

No, you still need a bunch of stuff that’s hard to come by in space: air, water, food. You need to mutate into something else, like the Andromeda strain, or something.

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ajay 05.13.13 at 11:07 am

The same logic would lead to the conclusion that birds have not evolved into things that can fly.

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Mao Cheng Ji 05.13.13 at 11:11 am

“the Andromeda strain”

…which (together with wikipedia) reminds me of the “Odd-Man Hypothesis” that would fit nicely (or nasty) in the Keynes’ thread.

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Lurker 05.13.13 at 11:13 am

Falkland Island are even a more recent Terra nullius case. They ere settled Bay the Spanish in the early 18th century, abandoned and permanently settled by the Brits only in 1830`s.

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ajay 05.13.13 at 11:18 am

Pitcairn Island too – settled in 1790.

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ajay 05.13.13 at 11:19 am

Actually, sorry, cancel that – there were earlier Polynesian settlers, but they were extinct by the time the island was discovered (and later settled) by Europeans.

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chris y 05.13.13 at 11:22 am

The cheapest and easiest solution (because it minimises the cost in and dependency on time, air, water and food) to long distance space travel is to have robots do it. Because it’s the cheapest and easiest solution, it’s the one that will probably be used. Note that this is a form of human exploration and colonisation of space; Homo sapiens is a tool using animal, and this will be tool use in the grandest tradition of our species. The detail that the tools will be artificially intelligent and probably self reproductive is neither here nor there. They may very well also outlast us: I can think of no better memorial.

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Mao Cheng Ji 05.13.13 at 11:25 am

“The same logic would lead to the conclusion that birds have not evolved into things that can fly.”

I honestly spent several minutes trying to guess what you meant here, but alas. Please, now I must know.

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Eric Drexler 05.13.13 at 11:37 am

@Brett â€”

This [interstellar flight] is a fun topic, but the implications of mechanical scaling laws for manufacturing throughput and considerations involving thermal fluctuations in small mechanical systems have rather more practical consequences for the world situation.

Was that a nanotechnology reference?

Yes, more or less, but this point in the history of ideas, the term high-throughput atomically precise manufacturing (a.k.a. â€˜APMâ€™) is much less ambiguous and prone to misunderstanding. Since I introduced the term in 1986, â€˜nanotechnologyâ€™ has come to mean (typically) eithersimple nanomaterials or pointless dancing nano-robots (a strange divergence, no?). APM refers to a well-understood prospective technology with large potential impacts on global economic development and climate change. Iâ€™m hoping to reboot a serious critical examination of the topic.

BTW, as I discuss in Radical Abundance (and outlined in a bunch of NPR interviews last week) thereâ€™s been surprising progress in relevant areas of atomically precise fabrication, but the progress has been in the molecular sciences and most of the results arenâ€™t called â€˜nanotechnologyâ€™. This situation has led to misperceptions regarding progress toward implementation.

I call interstellar flight a â€˜fun topicâ€™ because I used it as a distraction from more serious technical topics while writing the book.

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JGooders 05.13.13 at 11:51 am

#101 but does the the maths still work if you use the population of the colonists, as JQ does, not the current population of Australia?

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ajay 05.13.13 at 12:50 pm

116: birds require things like water, food and nest space, none of which are generally easy to come by in midair.

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Randy McDonald 05.13.13 at 12:53 pm

“The fact that no-one has sent a detectable signal in our direction suggests that intelligent life forms similar to humans are very rare.”

Not necessarily. The first attempts to detect signals directed towards us began only fifty-odd years ago, and it’s only recently that more systematic searches have begun for signals or evidence of artifacts. Certain things can be excluded–there don’t seem to be any Dyson Spheres within a few hundred light years of our solar system, for instance–but other things cannot. (It’s entirely imaginable that there might be ships moving about in the Kuiper belt even now, beyond our ability to detect them.)

The state of observational astronomy has advanced significantly over the past couple of decades, but not enough to come to any definitive conclusions about whether there is anyone out there nearby or not.

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Oscar Silverman 05.13.13 at 12:53 pm

Interstellar nuclear fusion propulsion is entering into a high conceptual maturity phase to become increasingly technologically feasible. http://www.youtube.com/v/VUrt186pWoA

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Cranky Observer 05.13.13 at 1:42 pm

= = = Moreover as J. Quiggan points out the technology to make Antarctica habitable is orders of magnitude less advanced than the technology to survive indefinitely in outer space. The same goes for the surface of the oceans and much of our orbit. We arenâ€™t going to run out of space any time soon, what we lack is the resources to make that space habitable. Which, incidentally, another planet doesnâ€™t get you any closer to than interstellar space: terraforming mars, or carpeting it in dome cities, is almost certainly more difficult/expensive than building an equivalent amount of just as nice orbiting habitat.

Of course the flipside of this is that colonisation and â€œshipsâ€ is the wrong framing, what we are talking about is building self sustaining habitats that can survive in space. After that, where to put them is a minor question, but â€œat the bottom of a gravity wellâ€ is rarely going to be the right answer. If they feel like visiting Alpha Centuri, the generations aboard during the â€œjourneyâ€ wonâ€™t be particularly disadvantaged compared to the ones at the destination.= = =

That’s basically the argument that the City Beautiful people and the advocates of mass exurbanization use to explain why New York City (particularly Manhattan and Brooklyn) cannot exist and, given that it does, will shortly be abandoned. _No one_ could possibly like living in those conditions (in the Village::on a planet) enough to keep doing it of their own volition; the whole thing will (soon collapse::move to the Oort Cloud). Might want to read some Jane Jacobs.

Cranky

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Katherine 05.13.13 at 1:59 pm

I used to feel optimistic and excited about the idea of space travel, although of course most of the facts and probabilities are unknowable right now, and will most likely remain so during my lifetime.

My optimism took a huge plunge when I heard a bunch of rich-as-f*cks declaring that we, humanity, could get everything we needed, resource-wise, from space, once we’d run out of it here. Just our own solar system is so big, we’d never have to worry about stuff running out, so let’s go forth and the plunder! I had a vision of the same type of rich-as-f*cks from a couple of hundred years ago declaring the same thing about going forth and plundering the Earth.

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Steve 05.13.13 at 2:29 pm

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reason 05.13.13 at 2:39 pm

Bob Pendelton @1
“Sending preserved human genetic material by small spaceships might be a feasible means of spreading the human species outside our solar system.”
Not sufficient unfortunately – unless someone invents a Robot mother.

In general I agree with the criticisms of the linear extrapolation of the costs.

But I anyway don’t think it is feasible. (And did you allow for the possibility that the planets are moving away from us possibly faster than anything we could send to them could move towards them. Or what the probability is that the spacecraft would be damaged or destroyed by radiation or collisions before it got there?)

126

And did you allow for the possibility that the planets are moving away from us possibly faster than anything we could send to them could move towards them.

If we’re doing interstellar travel, we’ll be moving faster than most things in this galaxy, so that’s not an issue.

Or what the probability is that the spacecraft would be damaged or destroyed by radiation or collisions before it got there?

Collisions are unlikely. Space is big.

Radiation is an issue, especially at high speed (as pointed out earlier). Shielding is a problem. Clarke (and others, probably) proposed a huge block of ice.

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Lee A. Arnold 05.13.13 at 3:45 pm

Jerry Vinokurov #95: “I seriously doubt that if the method were somehow better and the predictions more precise weâ€™d get better policy.”

–Nonsense, almost anything with a 100% harm rate won’t even be allowed into the marketplace, without a swell in general rage amongst We the People. Similarly on the other hand, the history of environmental litigation shows clearly that the toxic corporations depend heavily upon the lack of precision in scientific results to avoid prosecution. There is a whole bookshelf on this. What is the statistical probability of 3 degree rise in 100 years? It’s an open door to any “obtuseness” or “evil”.

“you donâ€™t need to be even a scientist to suspect that dumping sludge in a river is not a good plan”

–More nonsense, and quite the reverse, until recently. Before the mid-20th century, you could barely find a scientist to mount a credible argument against dumping sludge in a river, much less an argument from the rest of the population. I think there was maybe (1) Sitting Bull, and (2) James Joyce, in the end of Finnegans Wake. “Dumping sludge in a river is not a good plan” was in those days the expression of some sort of kooky, radical environmentalism.

In fact today, some scientists (and many economists) are in some cases still railing against “radical environmentalists”, sometimes by pointing out that there are things we still “don’t know”. And/or that therefore they should be balanced against some market efficiency.

The problem isn’t science, the problem is that some scientists are in a mental Sartrean “no-exit” loop on the issue. Their cheerleading for their cause (i.e. science) trips them up emotionally, and then they take everything as an attack on their methods, as you did, when it is really an attack on their blockheadedness.

What scientists ought to say is something like, “Complex systems cannot be predicted precisely, but generally we know that they do some bad things when forced, so we should take the precautionary principle.” Your grandma taught you something like this… But try to get a scientist to make a simple statement like that, without diverting into a boring lecture that their methods will be better “soon”, that we will know more accurately “soon”. We know enough already, and scientists are up against the necessary limitations of their necessary methods, and they are in this over their heads.

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mpowell 05.13.13 at 3:49 pm

NomadUK @ 32: This is missing the point. Or at least the point from my perspective. The reason to avoid ecological disaster is that it will cause lots of deaths. I don’t really care about humanity’s survival so much as I care about all the people that have to die to go from having humanity to not having it. If something wipes out all life on earth, I will not be much relieved by humanity suriving on another planet. All those people still died. You may have a different perspective, but I actually doubt that very many people truly have the moral priors that you imply. It is worth spending money to prevent massive deaths on earth from any number of sources, global warming or maybe asteroid collisions. But the goal is preventing avoidable death of human individuals.

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mpowell 05.13.13 at 4:14 pm

Lee @ 127: I think you’re pretty wrong about this one. Corporations will use whatever means they can to obfuscate the issue. And regardless of what scientists say, they will always be successful. It has nothing to do with the way scientists think and everything to do with the way knowledge of scientific authority is communicated to the general public and the operation of political power. How, as an average citizen with no ability whatsoever to understand the science, do I gain knowledge as to what the science says? I trust what people who I trust tell me. Many people trust Glenn Beck, and that’s enough right there to doom the enterprise. But some people trust scientists. And so the political opponents of climate change mitigation policy are happy to produce scientists to tell people it’s no big deal. How to do you tell the difference between a bought and paid for scientist and an honest one? You can’t, unless you can understand the science and the publication process, which 99% of the public is ignorant of.

You are looking in the wrong place for your explanation.

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Matt 05.13.13 at 4:46 pm

What price survival? Somewhere out there is a great, big rock, or a supernova, or a gamma-ray burster, and itâ€™s got our name on it. If weâ€™re still on this rock when it comes along, weâ€™re gone. Do we care enough to preserve this mess we call civilisation? If not, why bother at all?

The technology for providing an independent reservoir of humanity elsewhere in the solar system or galaxy devours its own “eggs in one basket” rationale as soon as it exists. If you have an automated industrial-base-inna-can, and have mastered closed-loop life support, Earth is as good a place to deploy it as anywhere else. Even in the aftermath of a gamma ray burst, asteroid impact, or global thermonuclear war, Earth is still far more hospitable to human life than Mars or the moon. If you have to grow all your food inside a sealed facility, and carefully filter air and water from the outside, that’s still easier than growing vegetables on Mars and wringing air and water from the stones.

On the other hand, suppose you don’t have the industrial-base-inna-can and closed loop life support systems worked out yet. What’s the humanity-preservation angle in launching Martian, lunar, or orbital colonies when they still depend on Earth? It’s like the backup plan for surviving global disaster is climbing the nearest tall tree. Humans don’t become meaningfully more extinction-resistant in space while their space colonies still need Earth.

In a few hundred million years the sun’s energy output will increase such that Earth becomes too hot for humans and other multicellular organisms. This might be mitigated by a space sun-shield, at least for some additional tens of millions of years. But eventually Earth will be swallowed up by a giant red sun. Is it time to flee the solar system then? Not necessarily. When the sun is a red giant, Neptune will be practically balmy, with a thick atmosphere and the whole surface turned to a liquid water ocean. The surface gravity is close to 1 g. If controlled nuclear fusion isn’t available by the time the sun exits red gianthood, I don’t think there will be any fleeing the solar system anyhow, but if it is, Neptune holds enough deuterium to power a technological civilization for billions of years after the sun stops providing adequate energy. The problem of how to escape the solar system in order to preserve humanity or its deep-future heirs is about the least urgent of all possible problems.

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Jerry Vinokurov 05.13.13 at 5:17 pm

Nonsense, almost anything with a 100% harm rate wonâ€™t even be allowed into the marketplace, without a swell in general rage amongst We the People. Similarly on the other hand, the history of environmental litigation shows clearly that the toxic corporations depend heavily upon the lack of precision in scientific results to avoid prosecution. There is a whole bookshelf on this. What is the statistical probability of 3 degree rise in 100 years? Itâ€™s an open door to any â€œobtusenessâ€ or â€œevilâ€.

This bears no relation to any recognizable facts about the world. To give just one example, cigarettes have, if not a 100% harm rate, then something quite close to it. And yet you can buy them pretty much anywhere. To give another example, drugs are routinely taken off the market if it can be shown that they increase the statistical risk of certain ailments (I’m thinking here specifically of Vioxx).

The less to take from this is emphatically not that science is useless or that you need 100% certainty, which is unachievable. The lesson is that there are significant political barriers to following through on the harm conclusions reached by scientists; these barriers are the result of vested interests controlling the flow of money and muddying the waters with fake science to influence public opinion.

â€“More nonsense, and quite the reverse, until recently. Before the mid-20th century, you could barely find a scientist to mount a credible argument against dumping sludge in a river, much less an argument from the rest of the population. I think there was maybe (1) Sitting Bull, and (2) James Joyce, in the end of Finnegans Wake. â€œDumping sludge in a river is not a good planâ€ was in those days the expression of some sort of kooky, radical environmentalism.

William Morris inveighed against the destruction of the environment more than 150 years ago. The idea that pollution is harmful is not a new one. Regardless, none of this contradicts my point, which is that the harms of pollution have been known for a long time. The mid-20th century was, actually, quite a long time ago; we are well past the point where the data has become conclusive. To go back even farther, the people who supervised the building of the London sewer system, intended to keep sewage from flowing into the Thames, didn’t even have germ theory to work with, but they understood on a basic, intuitive level that this presented a public health problem.

In fact today, some scientists (and many economists) are in some cases still railing against â€œradical environmentalistsâ€, sometimes by pointing out that there are things we still â€œdonâ€™t knowâ€. And/or that therefore they should be balanced against some market efficiency.

Oh yes, the “some scientists.” Nevermind that the overwhelming majority of scientists are politically liberal, accept the climate change consensus, etc. I guess as long as you find two cranks in an engineering department somewhere who either refuse to accept the truth out of spite or because they’re paid off by oil interests, you’d be technically right. As for “some economists,” well, we can talk about the perverse incentives of economists all day if we like.

The problem isnâ€™t science, the problem is that some scientists are in a mental Sartrean â€œno-exitâ€ loop on the issue. Their cheerleading for their cause (i.e. science) trips them up emotionally, and then they take everything as an attack on their methods, as you did, when it is really an attack on their blockheadedness.

What the hell does this even mean? I don’t understand who you’re trying to implicate in your tirade or what you want people to do. You’re thrashing about with meaningless diatribes about “no exit loops” and complex systems and god knows what else, and ignoring the simple and obvious truth that the problem is not, and has never been about the lack of data or model precision; the problem is always that doing the right thing is going to cost powerful interests some money, which they don’t want to pay. This isn’t blockheadedness at all, it’s just basic reality.

I “cheerlead” for science (to use your, again pejorative, language) because it’s our best bet for answering the factual questions that we need to answer. If you want to know the effects of global climate change, I don’t see an alternative to asking, you know, actual climate scientists. Denying this constitutes blockheadedness, and making up crazy nonsense about the alleged inaccuracy of scientific predictions is tantamount to ignorance about both how science works and how policymaking works. If I tell you that a collision between your passenger car and a semi is going to kill you, the proper response is not to then demand that I calculate the specific trajectory of the two vehicles before and after the collision, or else I just won’t be able to convince anyone that I’m right.

What scientists ought to say is something like, â€œComplex systems cannot be predicted precisely, but generally we know that they do some bad things when forced, so we should take the precautionary principle.â€

That is what they say! They say this all the time! Except not in your formulation, because that’s wrong (“forcing” is a neutral term that isn’t necessarily a bad thing) but yes, they will say things like “bad shit will go down if the planet warms 3 degrees.” I’m sorry that you apparently live in a cave and your internet connection only takes you to CT, but your ignorance of the state of discourse is hardly my problem.

Your grandma taught you something like thisâ€¦ But try to get a scientist to make a simple statement like that, without diverting into a boring lecture that their methods will be better â€œsoonâ€, that we will know more accurately â€œsoonâ€. We know enough already, and scientists are up against the necessary limitations of their necessary methods, and they are in this over their heads.

So after all this longwinded, directionless ranting, you’re actually agreeing with my basic premise, which is that: a) we do know enough already, and b) further accuracy isn’t going to sway people who aren’t already convinced by the incredible wealth of evidence we possess. I suspect that you’re not actually interested in any factual description of the state of science and how scientists communicate with the public, but much more interested in ranting about some abstract notion of technological hubris predicated on a mistaken conception of the limits of science.

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Charles 05.13.13 at 6:45 pm

What rot. Extrapolating future technologies from today’s technology is a vast mistake. Until Copernicus, everyone thought the Earth was the center of the universe. In the 19th century, we didn’t even know there was more than one galaxy. The speed of light has already been exceeded in quantum tunneling and in quantum entanglement. Quantum science is in its very infancy. This writer is like an ancient person predicting it would always take always a year or more to go around the Earth because only horse and slave-rowing boat travel could ever be used.

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John Quiggin 05.13.13 at 6:55 pm

@ajay That reminds me of a joke about Queensland with a (slightly adapted by me) punchline “Yes, our taxis are crap, too”

If you’d checked your history books, you would realise

* About half of us didn’t come from England
* We shared the ride, kids sitting on parent’s knees

* We didn’t all move at once – the latecomers are still arriving

So, the actual cost was 5 per cent of GDP, spread over 200 years or so. And of course, the cars came in handy at our end.

(Semi) seriously, colonising Australia by taxi is a trivially easy problem compared even to establishing a small settlement on Mars, let alone a sustainable population 1200 light years away

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Rich Puchalsky 05.13.13 at 7:04 pm

“The speed of light has already been exceeded in quantum tunneling and in quantum entanglement. ”

I thought of writing “Quantum!” as a one-word retort to the original post, but didn’t know whether people would treat it properly as a Terry Pratchett reference.

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Jerry Vinokurov 05.13.13 at 7:16 pm

The speed of light has already been exceeded in quantum tunneling and in quantum entanglement.

This is a mischaracterization of the state of affairs, at least to the extent that I am familiar with it (which, admittedly, is not a whole lot). See John Baez’s explanation as well as this more technical discussion. The upshot appears to be that the interpretation of information transmission at FTL velocities is far from well-established.

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Tangurena 05.13.13 at 7:19 pm

The problem with extrapolating Apollo program costs is that current spaceship technology involves trying to ship everything up that is all prepared on Earth. There is a large infrastructure involved in making the food and preparing it, and so on. The only real experiments in what sort of life-support system would be needed on long scales is Biosphere 2. Current manned space missions are more like sending an RV up there with a lot of cans of food, air scrubbers and bottled air. A Biosphere 2 type of mission would involve sending a much more massive can – about 1/2 acre per human. We have no experience with such size vehicles. Also, the experience of the Biosphere 2 crew was that those 8 people spent all their working day tending to 3 acres. And that land area was needed to provide the oxygen to support those 8 humans. A multi-generational ship to another planet will need to be much larger to support the genetic diversity needed for the colonists to survive to reach the destination. Of course you’re signing up future generations for lifetimes of serfdom, which is pretty much incompatible with any definitions of democracy or libertarianism.

A far more useful learning experience would be to build a cylinder with approximately 5-10 acres of land and use “Mars Cycler” type orbits. These are low energy orbits that would take a vessel from Earth orbit to Mars orbit (according to the wikipedia article on the subject, earth to mars trips range from 3 to 10 months each way). A permanent crew (probably all called Sam Bell if human, and Huey, Louie and Dewey if robots) could keep the ship in operation and carry passengers, cargo and other ships to Mars and back. The collapse of the country sending the astronauts is a real issue, after all, there were men on Mir while the Soviet Union collapsed under them, and they had no way home until the successor state sent up a rescue mission. A guaranteed ride home is a very important.

Logistics is where the problem is, and where the solutions will come from. Even if we make a conventional mission to Mars, it would be smart to ship a cargo capsule of food, water and oxygen every time there is a launch window (about every 26 months). Part the capsules in orbit around Mars and let them sit there for as long as it takes for a manned mission to get going. Since the US has a 70% success rate sending ships to Mars (about 50% success rate for Russia/Soviet Union), a lot of spare parts need to be sent.

As for “why should we do this?” If you measure how much the world spends on makeup each year, you can see where our current world’s priorities lay – and space is not one of them. People were complaining about the cost of the Apollo program back in the 1960s. But we’ll spend more on football each year than a manned mission to Mars costs. Or bailing out wall street. Maybe we can fund it with some sort of “reality show”, like The Truman Show – Mars Edition.

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Trader Joe 05.13.13 at 7:22 pm

@97
“If the drive converts energy to kinetic energy at 99% efficiency, or 99.99%, the remainder would still vapourize a 100,000 ton ship instantly. That energy flow would have to be dumped to space (comparable to the cooling of the entire sun-lit earth), without ever going through the mass of the ship in any way. Just the heat flux would be instantly destructive to any material.”

Fortunately when Doc Brown invents the flux capacitor this will no longer be a problem.

@133 The Group “Mars One” (at Mars-One.com) already has plans for the colonization of Mars which is to begin in 2023. Their venture will be privately funded and cost only \$6 Billion. Over 78,000 applicants to be colonists have already been received. I have no where near the science to understand if any of what they propose is remotely feasible (no doubt some of the more knowledgeable posters have a view – there are clearly some clever rocket-nerds on the strand), but a number of the backers don’t seem to think its that far fetched.

If anything like \$6 B is the number or even \$60B – it would seem like a lot could be learned from such a venture that could be applied to an even larger leap for mankind.

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Matt 05.13.13 at 8:05 pm

What rot. Extrapolating future technologies from todayâ€™s technology is a vast mistake. Until Copernicus, everyone thought the Earth was the center of the universe. In the 19th century, we didnâ€™t even know there was more than one galaxy. The speed of light has already been exceeded in quantum tunneling and in quantum entanglement. Quantum science is in its very infancy. This writer is like an ancient person predicting it would always take always a year or more to go around the Earth because only horse and slave-rowing boat travel could ever be used.

There actually is not evidence for information or matter travelling faster than the speed of light in vacuum, not in the laboratory nor outside of it.

Even ancient people understood that sound travelled much faster than horses, and light much faster than sound. They had natural examples of very fast phenomena even if they couldn’t imagine how human transportation might approach those speeds. Humans are no closer to building FTL transport today than they were in the time of Copernicus. Creating an FTL starship isn’t just Space Program writ large, it’s a delusional aspiration akin to building a mobile phone that uses astral projection instead of electromagnetism for communication. Science is as much about discovering natural limits as discovering natural opportunities. The light speed limit looks pretty firm.

There certainly are some great pieces of physics left to resolve: dark matter and dark energy, a quantum theory of gravity, the origins of inertia… But there’s no indications that any of these areas will allow you to travel faster-than-light once understood. People are building theories of FTL travel not because of some observed special relativity violation that needs explaining but because the actual observations point to answers they don’t like.

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Brett 05.13.13 at 9:48 pm

@Matt

On the other hand, suppose you donâ€™t have the industrial-base-inna-can and closed loop life support systems worked out yet. Whatâ€™s the humanity-preservation angle in launching Martian, lunar, or orbital colonies when they still depend on Earth? Itâ€™s like the backup plan for surviving global disaster is climbing the nearest tall tree. Humans donâ€™t become meaningfully more extinction-resistant in space while their space colonies still need Earth.

It’s like flying to Hong Kong to escape a house fire in NYC.

That said, if you thought there was a good chance that some type of collapse could and/or would occur at a systemic level, then interstellar colonization offers a greater degree of security against extinction. I’ve only seen that in SF novels, though, and it was based off of some tech assumptions that probably won’t hold up.

RE: Quantum Entanglement

If I recall correctly, they actually can’t send useful information between the pairs of entangled particles at faster than the speed of light.

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Matt 05.13.13 at 10:31 pm

Itâ€™s like flying to Hong Kong to escape a house fire in NYC.

How so? I’m talking about immature space colonies that still need regular supplies from Earth because they can’t survive on their own. Just like the International Space Station is an appendage of terrestrial society rather than an escape from it. There are people who want to build orbital, lunar, or Martian colonies on the strength of the “eggs in one basket” sound bite without figuring out how to be independent first. I think they’ve got it backwards: figure out how to become self-sufficient with a small number of people on Earth’s surface first, where mistakes are cheap, THEN start spending the much larger sums to do it away from Earth. That is if the justification given is genuine and they’re not just throwing one argument after another against the wall until one sticks and pays for Martian adventures.

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Lee A. Arnold 05.13.13 at 11:15 pm

mpowell #129: “Corporations will use whatever means they can to obfuscate the issue. And regardless of what scientists say, they will always be successful.”

I agree about the first one but not the second one. I have been following corporate p.r. and bad science on environmental issues since the late 1970’s. (I started first hand observing presentation meetings on suburban development on woodlands.) They will try anything. But they don’t always win, and one of the reasons they lose (there are several reasons) is when there is absolute certainty among the public that it is the wrong thing to do. If we are dealing with a complex system, that certainty cannot be brought about by the ability to make precise predictions, because that is impossible for formal scientific reasons. Obviously it also sends some people into spams of rhetorical confusion, an added boon for the evil corporations.

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Bill Jones 05.13.13 at 11:28 pm

As long as the fuckers on my list die before I do, I have no problem with extinction.

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Lee A. Arnold 05.13.13 at 11:40 pm

Jerry Vinokurov #131: “So after all this longwinded, directionless ranting, youâ€™re actually agreeing with my basic premise, which is that: a) we do know enough already”

Thanks for finally noticing what should have been obvious from the start. You appear to believe that when someone points out that the inability to predict complex systems gives an inroad to corporations who want to stop policy, that constitutes an attack upon the science itself. That is inept. As for, “b) further accuracy isnâ€™t going to sway people who arenâ€™t already convinced by the incredible wealth of evidence we possess,” this is surely nonsense. But again, you are likely to misunderstand this comment to be an attack on science instead of an observation of how real people react to things.

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chris heinz 05.14.13 at 1:01 am

Very nice, thanks.

My read on the Fermi Paradox is, temporal window in which tech civilizations use discernable EM radiation is very small. What, for us, 60-70 years? Before it all goes to fiber and short range wi-fi?

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Salient 05.14.13 at 1:08 am

No indeed, since plutonium does not exist in nature. Itâ€™s an entirely artificial element. // So, actually, our planet is extremely unusually plutonium-rich, in that it has a non-zero amount of plutonium in it.

Oh. I was thinking of uranium-like substances and vaguely remembered that we sent out Voyager powered by plutonium decay, so, must be what interstellar travelers need, amirite? Serves me right for not popping open Wikipedia. The article did contain the slightly strange sentence Inhaled plutonium has been shown to lead to lung cancer in experimental animals. (Hmm, good thing we never tried it in the real animals, then. But what kind of mad, mad scientist has been creating experimental animals and then irradiating them???)

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Jerry Vinokurov 05.14.13 at 1:48 am

Thanks for finally noticing what should have been obvious from the start.

How bizarre. You start off by talking about “ratiocination” and its inability to predict trajectories of complex systems; I point out that this is simply a feature of our world and nothing can be done about it, and furthermore that the things we can do are more than sufficient to convince those who can be convinced; you then accuse me of point-missing despite the fact that you have, in the end, come to agree with the very point I made in my first response to you. If it was so “obvious” why did you spend so much time ignoring everything I was actually saying?

You appear to believe that when someone points out that the inability to predict complex systems gives an inroad to corporations who want to stop policy, that constitutes an attack upon the science itself. That is inept.

Look, first of all, you really didn’t bother to understand the basic technical aspects of what you were talking about. In particular, you resisted, and may still be resisting (I can’t tell for sure), the central point that I keep hammering, which is: understanding large scale dynamics of complex systems is enough. It’s enough to tell you a great deal about what will happen if those dynamics are altered, and there’s no serious debate about this point.

The other bit which for some reason you are failing to acknowledge is that literally any measure of uncertainty is enough for those who wish to scuttle science-based policy to jump in. Given that Certainty with a capital C is an impossible standard to meet, any wiggle room at all will allow people to play god-of-the-gaps type games with error margins. This is a fundamental fact about the world we live in, and it’s something scientists have understood for many decades now, if not longer. What doesn’t make sense on the basis of this information is arguing that some kind of “technological hubris” is at fault for the problems of actually effectuating policy. I mean, it’s not that there’s never any tech hubris in general out there, it isn’t to blame for the problems of modeling climate change and species extinction.

None of this constitutes an “attack on the science” in and of itself, but this does:

Because in this situation, all that scientists do is point to statistical aggregates of results. You know that 3 degrees is coming, more or less, in a century, more or less â€” but golly, it turns out that isnâ€™t good enough, yet.

Regardless of whether you intended these two sentences to be pejorative, they are. You’re mischaracterizing the state of the science, the information that it gives you, and the effect it has on policy discourse. You’re basically saying that if scientists could do the impossible, that would be enough, but they can’t, and that’s not good enough, even though it obviously is good enough given what we actually know.

There’s no way to maintain this as a coherent position about what scientists are actually capable of delivering and what the policy implications of that delivery ought to be.

As for, â€œb) further accuracy isnâ€™t going to sway people who arenâ€™t already convinced by the incredible wealth of evidence we possess,â€ this is surely nonsense.

No, it isn’t. The problem here, again, is that you don’t seem to understand either the standards of evidence in play, or what the research is actually telling us. I won’t be so bold as to say that there’s no further data out there that could be marshaled on the subject of climate change, but it’s pretty close: we’ve got satellites, ice cores, tree rings, species migrations, ocean level gauges, and finally, basic physics. It’s not any one thing, but you take the intersection of all those pieces of data, you get a comprehensive picture of what’s going on with global climate. At this point, any refinement that we get to this modeling paradigm is going to make some difference at the margins but it won’t change the overall conclusions. If “total accuracy” is pictured as a mine of gold, then we have already exploited something like 95% of that mine; sure, it would be nice to get that other 5%, but it’s not going to make a terribly large difference in the end.

But again, you are likely to misunderstand this comment to be an attack on science instead of an observation of how real people react to things.

By the criterion you have set forth, for people to be convinced by the extra accuracy, it would require that science deliver the impossible. By setting that up as the standard, you are effectively making a critique of science: you are saying that we need a standard of a particular strength, but science has failed to deliver it. And what I’m telling you, and what any scientist will tell you, is that the standard is just impossible to meet. That’s not a function of any sort of Hobbesian “ratiocination,” it’s just a basic fact about the world. The tools we have at our disposal cannot, even in principle, produce what you ask, but unfortunately we cannot throw away those tools and get new ones that can. Demanding these outlandish things only plays into the hands of those who want to spread misinformation about the levels of confidence that scientific research programs can actually deliver.

I will restate my basic thesis, as regards climate change: we understand the gross-level dynamics reasonably well. We know the different components that are driving global warming. We have very reasonable guesses for what will happen to different parts of the world as the globe warms, although necessarily those guesses come with rather wide error bars. At this point, it’s not about precautionary principles, or anything else: it’s about averting global catastrophe. There are people who do not accept this consensus, but they cannot be convinced by any improvement in accuracy of global climate models. The kinds of accuracies that might theoretically convince them are unavailable as a matter of principle. Therefore, the right thing to do is not to get bogged down in the small-time details of whether we can shave another significant figure off our error margin, but rather to push the fact that climate scientists have pretty unambiguously come to a consensus about what’s happening and why. Getting involved in critiques of ratiocination is misguided and plays into the hands of the deniers, while generating infighting between people who should be allies (e.g. this thread).

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Patrick 05.14.13 at 2:29 am

The time for the sun to orbit the galactic center is about 250 million years.(galactic year, 18 having elapsed since the earth was formed.) That is a long time, but we’re also traveling an extraordinary distance. During that time, the earth is oscillating up and down out of the galactic ecliptic. (Like a buoy in the ocean, bouncing up and down.)

What this means is, although there are no stars that we can easily reach now. Many,many stars will venture quite close to us on the scale of a galactic year.(and in far less time.)

If habitable planets are not too rare, our best bet is to wait for one to come to us, then send people across when our stars are closest. This is not too different from how orbital windows work when sending spacecraft to Mars: Reaching habitable planets is expensive now, but it will not always be so, even if we do not develop any amazing new technologies.

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Patrick 05.14.13 at 3:05 am

To put it in perspective. The earth has gone about 90 degrees around the galactic center since dinosaurs went extinct. In that time numerous stars will have passed within a light year of earth. Some of them probably had habitable planets.

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William Berry 05.14.13 at 3:10 am

MPowell& Jerry Vinokurov: Yeoman work, but you are probably wasting your time. If I can be forgiven the snark, let me just say, though I am very interested in these issues, I probably know more about quant lab, making aluminum, and labor activism than I do about space travel and science and public policy, and I suspect that Lee knows more about plumbing!

To the OP: I believe the technical details are pretty much irrelevant. This is not a question for our age. I am convinced that the future of space exploration for the next few hundred years lies in our solar system. For the most part, planetary settlement will not be an issue, as we will mostly not waste energy in gravity wells (other than escaping our own). Exploitation of asteroids and comets in the asteroid belt and the Oort Cloud will be mostly robotic (why would we risk lives and treasures given the advances in computer technology and the almost certain eventual perfection of A.I.s, or at least very sophisticated expert systems?). A virtually inexhaustible supply of solar energy will power orbital habitats providing magnificent living environments for millions (eventually billions) of people, and also providing power for super-efficient ion engines moving vast, robotic cargo vessels throughout the system.

The best part of this vision for living in space without planetary settlement, is that it is congruent with the course we should be taking anyway. We should stop wasting time and money talking about the Moon and Mars and interstellar travel (all will come in their time). We need to get to work on asteroids, beginning with detection and diversion. This technology will be the basis for the exploitation of space resources that can eventually be put to use in developing human habitats in space.

My dream for Earth is much like J.W. Mason’s; I just come at it from a different direction. The genie of technology cannot be put back in the bottle. And the idea of humanity, as a race of ten or more billions, being able to live in harmony with nature, is as fantastic a dream as interstellar travel. Our moral course, with respect to nature, will be to sequester ourselves from nature in such a way that it will be left on its own. This is only a dream for a far future, of course, as we are already so far into the boundary region for survivability of life on Earth that we are probably past the point of no return. We can expect, at the very least, a massive dieback of life (including humans) on the planet within the next hundred years or so. Let’s hope that in that dreadful future there will be a sufficient number of humbled, intelligent, and thankful human survivors to get things on a sensible, sustainable course.

Regardless of the accuracy (or inaccuracy) of particular technical details and extrapolations, I think JQ is dead on. It is interesting to dream of interstellar travel, but it is just that, a dream.

One last note: I think the idea that the lack of intelligent signals from space is meaningless. This issue has been dealt with extensively by many thinkers and writers. While I am not down with Vernor Vinge’s libertarian, “free-market” political ideas, he is very good in this area; indeed, I find him completely persuasive. Going from memory here (as usual, I am too lazy to Google!), the argument for why we haven’t heard “them” runs something like this: If they are civilized at all they are highly advanced. When they have reached our level of development and are capable of radio transmission, there might only be a very short period in which they would be putting out detectable signals. Given the time-scales involved in the life of the universe, and the interstellar distances, the laws of probability suggest that it would be a fantastic coincidence that we would be listening during the same short time period (say, one to two hundred years; shorter, the more intelligent they are) that they were transmitting. Why do advanced civilizations stop transmitting? (After all, if they are Type II civilizations, with the ability to dispose of all the energy resources of their planets, as well as much of that of their star, they could build transmitters of incredible power.)They stop because they are smart. They know that the universe is a frightfully dangerous place. There is no reason to suppose that all advanced civilizations are completely benign. Even if well-meaning, they might be inadvertently destructive to lesser civilizations. So, advanced civilizations learn to keep quiet. Maybe this is what we should do; just STFU and go quietly about our business, here on our own world and in our own backyard.

Also, what Patrick said. It will happen someday. (That is, if we don,t kill ourselves and every other living thing on Earth before it has a chance to happen.)

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Lee A. Arnold 05.14.13 at 3:16 am

Jerry Vinokurov, as I predicted, once again you entirely misinterpret my comments to be an attack directed at the science.

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Omega Centauri 05.14.13 at 3:50 am

ajay “our planet is extremely unusually plutonium-rich, in that it has a non-zero amount of plutonium in it.”
The notion that tarnsuranic elements are *NEVER* found in nature bugs me. It just ain’t so. There is no law in nature that says a stray neutron can’t merge with a U-238 nucleus. And that Uranium was created in supernova thermonuclear blastwaves. Again no sign from god that say’s STOP at Uranium. So all sorts of natural exotic heavy elements do in fact exist in nature. Its just that on planets old enough to have generated -or support life, they will be exquisitly rare. But they will exist wherever macroscopic amouts of Uranium are present.

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Omega Centauri 05.14.13 at 3:51 am

tarnuranic => transuranic

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Lee A. Arnold 05.14.13 at 3:54 am

Jerry Vinokurov, Wait a minute, there is something interesting there: You write, “the things we can do are more than sufficient to convince those who can be convinced,” as well as, “There are people who do not accept this consensus, but they cannot be convinced,” and further above you wrote, “further accuracy isnâ€™t going to sway people who arenâ€™t already convinced by the incredible wealth of evidence we possess.”

Yet you also write, “literally any measure of uncertainty is enough for those who wish to scuttle science-based policy to jump in”, and then, “any wiggle room at all will allow people to play god-of-the-gaps type games with error margins,” and, “Getting involved in critiques of ratiocination is misguided and plays into the hands of the deniers, while generating infighting between people who should be allies (e.g. this thread).”

So is it your opinion, then, that the rhetoric of the reportage of the science is at an absolute top limit, where no more supporters for mitigation policy can be gained, but some can be lost (due to infighting, etc)?

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Jerry Vinokurov 05.14.13 at 5:31 am

So is it your opinion, then, that the rhetoric of the reportage of the science is at an absolute top limit, where no more supporters for mitigation policy can be gained, but some can be lost (due to infighting, etc)?

No, it’s not. The rhetoric is actually abysmal, and I believe that it’s connected to the other things I’m talking about. Here’s the rhetorical problem, in a nutshell: even the tightest scientific investigations are accompanied by errors. When the problem is not easily constrained, as is the case with large, complicated systems like a global climate, those errors are going to be larger. But most non-scientists don’t really understand this whole “error bounds” thing very well, so the rhetorical maneuver that deniers like to pull is putting the emphasis on the uncertainty of the measurements. Where the reportage becomes abysmal is that the reporters don’t understand it either, so instead of putting the emphasis on multiple convergent lines of evidence, they allow deniers to spout their nonsense uncritically. This is what I’m getting at when I say that any margin of error allows dishonest people who want to exploit that margin to jump in, if they’re allowed to do so without being challenged.

I do think that we can win supporters, but I don’t think we can do it by improving the accuracy of the results. I could be wrong about this, but everything I’ve read leads me to believe that most of the lines of evidence that are available have been exploited, which means that improvements will be marginal. We are unlikely to discover some new evidence that’s going to revolutionize our understanding of global climate. The correct thing to do is to emphasize just how much it is that we do know, which is a lot. Point out the changes in migration patterns, the disappearing ice of the Arctic, the drought we’re experiencing across many parts of the globe. Talk about the fires in the western U.S. These are things that are happening, right now, to people; if you get all that information into the conversation and never let up, you have some hope of getting across to people. But I don’t think it’s realistic to think that if we shave another 5% off the error or something the public is going to go, “Oh, now we believe you.” That’s just not how science is perceived.

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Lee A. Arnold 05.14.13 at 6:16 am

You are talking about a “preponderance of evidence” argument. Can it stand alone, or is it also necessary to connect that to a “tipping points” argument? I.e., explicitly mention that systems like this will remain precisely unpredictable, but that systems like this also show general regularities: oscillations, increased oscillations with forcing, tipping points into catastrophes, etc?

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Neville Morley 05.14.13 at 7:00 am

Don’t people read von Daniken any more? We have plenty of evidence that interstellar colonisation is possible, because it happened to our own planet.

Is there an emoticon for “I don’t really mean that, please don’t fire me”? But I did wonder what evidence was being considered above for determining the question of whether or not interstellar travel had taken place, given the argument that it should have taken place by now if it were possible, if not the results of the investigation of Earth’s past.

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John Mashey 05.14.13 at 7:42 am

The fact that we have not detected civilizations:
a) Means only that no civilization has taken the trouble to spend enormous energy resources to narrowcast at us (not knowing we’re here). To see that now, they have to have been sending X years ago if they are X light-years away.

b) Forget about anyone detecting our broadcast radiation or us detecting anyone else’s at any Earth-like planet’s remotely-plasusible level, the inverse-square law attenuates the signal very quickly.

See Post at Barry Brroks, and my comment, from years ago.

Or see the ongoing discussion at RealClimate.

“The energy requirements are simply too high for civilizations at our level to see each other, especially if expecting to intercept radio or TV. I recall reading sci-fi stories where aliens light-years away have been trying to learn about us from old TV comedies. I donâ€™t think so, see SETI FAQ, which works the numbers:

â€œEven a 3000 meter diameter radio telescope could not detect the â€œI Love Lucyâ€ TV show (re-runs) at a distance of 0.01 Light-Years!â€ One needs narrowband:
â€œIt appears from the table that effective amateur SETI explorations can be conducted out beyond approximately 30 light years provided the processing bandwidth is near the minimum (approximately 0.1 Hz), the system temperature is minimal (20 to 50 Degrees Kelvin), and the EIRP the source (transmitter) is greater than approximately 25 terawatts.â€

Of course, 25TW is somewhat more than current total power used by humans.

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John Quiggin 05.14.13 at 9:28 am

@JM That’s encouraging to know. Given the impossibility of interstellar travel, it’s perfectly possible that intelligent life is thriving throughout the galaxy, having worked out that attempts at communication aren’t worth the trouble. If so, maybe we can survive too.

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Monte Davis 05.14.13 at 12:07 pm

John @57: The significant distinction is broader than IT vs. transportation technology: it’s IT vs. almost every other technology. Moore’s “Law” and its corollaries hold sway because IT functions and results are almost completely independent of their physical instantiation: like Turing sez, as long as you can read, write, store and erase bits, it doesn’t matter if you use graphite on paper, abacus beads, gear teeth, vacuum tubes, transistors, or spin states.

Ralph Gomory said it at IBM forty years ago: Take the materials of a 2000-lb. car and make 2000 perfect little replicas, and they’re toys: even if the engines worked (which they wouldn’t because of square/cube scaling) you couldn’t drive or ride in the microcars. But do the same with a 2000-lb computer, and the 2000 mini-replicas not only work — they work better. Ditto for most other exemplars: even if Intel could make 10,000 tiny perfect grain combines, bulldozers, oil tankers or Saturn V rockets on a wafer, they’d be useless curiosities.

There are meaningful comparisons between IT and other information-centric domains such as broadcasting, printing, language, and genetics/evolution. Beyond that, not so much. The prevalence of “Why can’t we have Moore’s Law for [technology X]?” memes tells us more about this era’s (entirely natural) excitement over IT than about the real prospects for progress in technology X.

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AndyfromTucson 05.14.13 at 12:49 pm

“The fact that no-one has sent a detectable signal in our direction suggests that intelligent life forms similar to humans are very rare.”

For more evidence that intelligent life is very rare, just look at the history of the earth. Large complex animals have existed on earth for 230 million years, yet intelligent animals only evolved (approximately) 2.5 million years ago. If evolution always favors the development of intelligence you would expect it to show up relatively soon after complex vertebrates developed. Look at flight: the ability to fly is a very complex trait (so complex human engineers still haven’t replicated the flight of a bird) yet it showed up long before intelligence. The late development of intelligent animals suggests that perhaps it was a fluke, brought about by a rare combination of circumstances.

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Jerry Vinokurov 05.14.13 at 3:37 pm

You are talking about a â€œpreponderance of evidenceâ€ argument. Can it stand alone, or is it also necessary to connect that to a â€œtipping pointsâ€ argument? I.e., explicitly mention that systems like this will remain precisely unpredictable, but that systems like this also show general regularities: oscillations, increased oscillations with forcing, tipping points into catastrophes, etc?

I don’t know if all of it is necessary, but it’s sure to come up during discussions. Certainly the “tipping point” stuff (e.g. the melting of the Arctic permafrost and the potential for the ensuing runaway warming) is definitely something that people should be aware of. I think in any discussion, you’re going to end up with people saying things like “but they can’t exactly predict the weather blah blah blah” and at that point you have to explain to them that there are different scales (temporal and physical) and on large scales, we have a lot of information about what’s going to happen. There are strong macro-scale regularities within the global climate system and we know a great deal about how they function.

Fundamentally, I believe that as a scientist, you never want to be dishonest with the public, but that doesn’t mean underselling your work. A lot of hedging that you see from scientists when they’re asked to give public statements has to do with the fact that good scientists understand that much of their work is provisional, comes with errors, and so on. So on the one hand you certainly don’t want to compromise that by promising people the moon. But on the other hand, you have to take a firm stand regarding what you do know, and back it up by explaining how the evidence comes together to give you the whole picture. A lot of scientists now are waking up to this and being much more aggressive about spreading their message than they were 10 years ago. Even the media climate has changed, although not as much as it should have; there less patience overall with the denialist tactics, and more attention being paid to the actual science. It’s still bad, but it’s not as bad as it used to be.

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John Mashey 05.14.13 at 4:15 pm

JQ@1158
Yes, although there’s always the possibility that some civilization around a nearby star (a few tens of light years) decides to spend the energy to narrowcast at each nearby star for a few years, presumably with a much longer budget cycle to cover thousands or millions of years. I.e., the hope would be that they send for a while, get noticed, and the receiver can build an equivalent transmitter, and send back.

Different diesciplines think on different time scales. Computer folks think in nanoseconds, geologists in million of years.
Astrophysicists/cosmologists:
one was giving an after-dinner talk to a general audience.
She said something about something “recent.”
I raised my hand and said, “could you explain to people what ‘recent’ means to you?
“”Oh, within last 2 billion years.”
Likewise, Proxima Centauri is really, really close…

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Jerry Vinokurov 05.14.13 at 4:22 pm

As the joke goes, astronomers do it to within an order of magnitude.

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Brett 05.14.13 at 5:04 pm

There’s also always the chance that a habitable planet within a couple of light years has civilization that might pick up on radio signals before it becomes impossible to tell them from background noise. There are a lot of potntial planets we’ve missed because of technical limitations (Kepler can only see planets for solar systems it can see “edge-on”.

What does harmony with nature mean in this discussion? Nature itself isn’t harmonious – we used to believe in the idea of the climax ecosystem, but ecologists have abandoned it with more evidence. And a lot of landscapes considered pristine were heavily modified by ancient people.

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John Mashey 05.14.13 at 6:04 pm

One more time even if aliens of our level at Proxima Centauri have Arecibo radio telescopes pointed at us, they will not see our radio or TV broadcasts.
The inverse-square law is brutal.

Consider the exo planets, specifically detection methods. One if the methods is to detect change in brightness as a planet transits in front of a star. That tells us that if a civilization could build a (big)planet-sized set of Venetian blinds and position them between us and their sun, and they used them to modulate sunlight, Kepler could see that, although the bit rate wouldn’t be very high. Of course, no one would do that, but it hints that the energy requirements are within an order of magnitude or two of solar energy incident on a planet at that distance.

By the way for an inspiring story about the Kepler satellite, read about William Borucki, who has spent 30 years of his life making it happen.
http://m.washingtonpost.com/politics/federal_government/looking-for-signs-of-life-in-the-universe/2013/05/06/f6008072-b662-11e2-aa9e-a02b765ff0ea_story.html

There’s a good article in him in Science as well.

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Tangurena 05.14.13 at 7:04 pm

The fact that we have not detected civilizations:

Could also mean that their species uses DRM to encrypt everything and their radio waves are indistinguishable from background noise. Just think about how our current TV waves would appear to a distant observer: viewable from the 1950s to 1990s and decreasingly viewable since then, and gone by the final switchover to digital TV broadcasting. It is quite possible that their cleartext TV signals passed the Earth in 1350 (to pick an arbitrary year) – that we didn’t have electronics invented during the narrow window of time when it would have been possible to perceive their signals.

I predict that all alien races have lawyers and lobbyists pushing their own copyright term extension acts and digital restriction mismanagement.

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Brett 05.14.13 at 7:06 pm

Kepler is a gem. I’m hoping we get at least another 2 years out of it before it breaks down too much to be useful.

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mike shupp 05.14.13 at 9:27 pm

I suspect most commenters here have not followed the discussion over in Dan Kuehn’s Facts & Other Stubborn Things website, so I trust I won’t be violating etiquette too much by quoting something I said there:

Making a more serious point, on rereading Quiggin’s original post at Crooked Timber, I tend to think he’s less interested in the economic nuts and bolts of star travel than with philosophical issues: Given the sizable costs of money and time, and the likely low reward for such expenditures, why should anyone even want to go to the stars? Which reduces to existentialism, as best I can see; the answers aren’t to be found in economics or engineering, even if economists and engineers — and all the rest of us — choose to grapple with such questions.

http://factsandotherstubbornthings.blogspot.com/2013/05/a-question-for-quiggin-on-interstellar.html

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Ragweed 05.14.13 at 10:13 pm

Tangurena @136
Also, the experience of the Biosphere 2 crew was that those 8 people spent all their working day tending to 3 acres. And that land area was needed to provide the oxygen to support those 8 humans. A multi-generational ship to another planet will need to be much larger to support the genetic diversity needed for the colonists to survive to reach the destination.

Which brings up another challenge for interstellar travel – the biosphere folks could rely on sunlight from a local star for energy to produce the oxygen, food, etc. A space colony on one of the inner planets could as well, but once out beyond Saturn or so solar energy becomes rapidly useless. Travel in the cold dark regions between stars will have to have its own power for any sort of life support.

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Lee A. Arnold 05.14.13 at 10:16 pm

Jerry Vinokurov #161:
Okay, so we won’t use the tipping points argument unless we are asked, and we are going to stick to the preponderance of evidence argument. Note two things about this: One, that the preponderance of evidence argument is a regular rhetorical way to overcome the lack of precise prediction (or proof, in the legal system), and this re-enforces my beginning point, that the lack of precise prediction is the central problem of climate policy.

Number two, the preponderance of evidence argument is easily defeated by the “obtuse” and evil”, who will then say, “Things have always changed anyhow!” In fact, they ARE saying that. So you would need to pile on a huge preponderance of evidence, and there is a sort of self-limiting upper bound in this situation, largely due to the limited amount of attentional timespan and the limited number of hours in the day for an individual person to intake media.

What is more likely to change things is fear, in fact, a “mild” tipping point. If, for example, an unpredicted heat spike crashes world agriculture for a year, before the temperature returns to the main trend, it would cause tens of millions of deaths and a global panic. Horrible, and people over at RealClimate assured me that it is unlikely — and so I am convinced that it will happen in a decade or two.

“Itâ€™s still bad, but itâ€™s not as bad as it used to be.”

It was actually better in the late 1970’s. We didn’t know as much then, but to anybody paying attention, the climate was going to be a big problem. I remember a Bioscience study in the mid-80’s that discussed the possible effects of climate change on biodiversity, and I have been paying very close attention ever since. I think I was the first person to formulate the argument that climate change might accelerate extinction, due to previous habitat fragmentation by humans, which inhibits some species migration and replenishment. I could know more about climate change than you do. With one big exception: my interest was never in learning the mathematical models because I already knew from ecosystem studies that they would not be precisely predictive, and so something else was needed. To confirm my fear, corporations became adept during the Reagan years in using the uncertainty of science against scientists, who were easily made to look like fools in public fora.

One reason for this (though not the only reason) is that scientists did not have the language to counter the complaints for more evidence and better prediction. This is because complex systems indeterminacy had been restricted to a few people looking at general systems, and most scientists were unaware of it, or in denial that it would affect their studies, or they were unable to muster the words to help the public understand it, and were caught like deer in the headlights at public discussions.

Since I never doubted that the climate and biodiversity situations would get worse, my interest thus became the public rhetoric of uncertainty. I predicted this was going to be a pointed political fight, 30 years ago. When RealClimate started I predicted the Inhofe committee was going to diss the climatologists and I’m not sure that they believed me until it happened. So I am glad to hear that scientists are finally waking up. It is yeoman work indeed.

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John Quiggin 05.14.13 at 11:01 pm

A minor point regarding the notion that exploitation of space resources might provide a way out of constraints on Earth. The technology for unmanned (sic) moon landings is old and fairly reliable, but no-one has bothered sending anything there since the last Soviet Luna mission in 1976 – various countries have done crash landings to demonstrate the fact that they have a space program, but that’s about it. Revealed preference arguments are always tricky. Still, if there was any good reason to think that the moon might have economically extractible resources, surely someone would have at least gone to take another look sometime in the last 40 years. AFAIK, not only has no-one done this, but there are no plans for even preliminary steps in this direction.

We’ve got one planet, and if we mess it up, that’s that.

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Jerry Vinokurov 05.15.13 at 12:17 am

Okay, so we wonâ€™t use the tipping points argument unless we are asked, and we are going to stick to the preponderance of evidence argument. Note two things about this: One, that the preponderance of evidence argument is a regular rhetorical way to overcome the lack of precise prediction (or proof, in the legal system), and this re-enforces my beginning point, that the lack of precise prediction is the central problem of climate policy.

No, it doesn’t work that way. “Preponderance of evidence” isn’t a rhetorical anything; it’s just the fact of the matter about the state of the research. The lack of precise prediction is a problem for climate policy only in the sense that it’s a problem for policy in general; a substantially higher level of certainty is unavailable.

Now, of course that’s a problem in the sense of effectuating policy, but again, it’s a problem in general. The certainty we have with regard to climate change is far greater than the certainty on which many economic policies have been based. And yet the relatively poor accuracy of economic models hasn’t stopped anyone from doing economics and implementing policy. Why is that? The answer can’t be in the accuracy of models in general.

Number two, the preponderance of evidence argument is easily defeated by the â€œobtuseâ€ and evilâ€, who will then say, â€œThings have always changed anyhow!â€ In fact, they ARE saying that. So you would need to pile on a huge preponderance of evidence, and there is a sort of self-limiting upper bound in this situation, largely due to the limited amount of attentional timespan and the limited number of hours in the day for an individual person to intake media.

This is a problem, but I don’t know what to say; the obtuse and evil will always fight you. I’m saying that, from any objective standpoint, we know enough to know what we need to do. The difficulty is convincing people of this. But we do have enough evidence to convince the people who are capable of being convinced by evidence; for the others, we will never have enough evidence anyway, so bemoaning the fact that we can’t do the impossible isn’t very productive.

Let me provide a concrete example: the evidence that smoking causes cancer is mostly statistical. It’s a combination of studying the effect of the impact of substances contained in cigarettes on tissue (the micro-level) and an epidemeological studies (the macro-level) that track smokers over time. Now, there are people out there who smoked all their lives, never got cancer, and died at 90. Clearly we don’t have the tools to individually project every person’s “cancer trajectory” but that hasn’t stopped the medical community from linking smoking and cancer. Nor has it stopped plenty of other policy actions. We vaccinate, we pay attention to air quality, etc. All of these things are, to some extent or another, based on statistically aggregated evidence.

So there are plenty of examples of policies being implemented on such grounds. The question we should ask is why it’s been possible to accomplish that. I think the answer has many components, not least that, e.g. smoking affects people directly, produces visible evidence of harm, and so on. It’s also a smaller scale; it’s easier to conceptualize “if I put burning tar into my lungs this is not good” than it is to conceptualize “putting an invisible, otherwise harmless gas into the atmosphere leads to catastrophic warming two hundred years later.” It’s like asking people to conceptualize cosmological scales, it’s alien to them.

What is more likely to change things is fear, in fact, a â€œmildâ€ tipping point. If, for example, an unpredicted heat spike crashes world agriculture for a year, before the temperature returns to the main trend, it would cause tens of millions of deaths and a global panic. Horrible, and people over at RealClimate assured me that it is unlikely â€” and so I am convinced that it will happen in a decade or two.

Yes, unfortunately that’s probably the case. There’s an apt Russian proverb to this effect, translated loosely as “a man won’t cross himself until he hears thunder.”

One reason for this (though not the only reason) is that scientists did not have the language to counter the complaints for more evidence and better prediction. This is because complex systems indeterminacy had been restricted to a few people looking at general systems, and most scientists were unaware of it, or in denial that it would affect their studies, or they were unable to muster the words to help the public understand it, and were caught like deer in the headlights at public discussions.

Maybe this was true in some fields, but at least in climate science, I know that Lorentz did his work on chaos in the late 60s. Feigenbaum did his pioneering work in the mid-70s. And of course, as previously noted, the three-body problem goes back to Poincare at the end of the 19th century. In physics, at least, people were well aware of these sorts of things, although my general impression is that a lot of that research didn’t migrate out of physics to other fields until the mid-80s.

Since I never doubted that the climate and biodiversity situations would get worse, my interest thus became the public rhetoric of uncertainty. I predicted this was going to be a pointed political fight, 30 years ago. When RealClimate started I predicted the Inhofe committee was going to diss the climatologists and Iâ€™m not sure that they believed me until it happened. So I am glad to hear that scientists are finally waking up. It is yeoman work indeed.

I think there’s something to be gained from reimagining how we talk about uncertainty, sure. But you can only do so much. Rather than dwell on what we can’t, and will never be able to do, I’d much prefer that we focus on what we do know and can do. Our lives are governed by fundamental uncertainties, but we keep living them anyway.

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John Quiggin 05.15.13 at 12:42 am

I haven’t been following this side debate closely, but the mention of smoking and climate change is interesting. Not only were the issues similar but (at least on the anti-science side) the same people and organizations were fighting, using the same tactics. Some have moved on from tobacco, but there are plenty of Repubs and libertarian thinktanks (eg Heartland and Cato) still pushing on both fronts.

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gordon 05.15.13 at 12:59 am

Jerry Vinokurov, Lee J. Arnold…

Some time back, on another blog, I suggested that the distinction is a bit like the legal distinction between standards of proof; “balance of probabilities” and “beyond reasonable doubt”. I suggested that there was little point in offering a balance of probabilities proof to somebody who was only interested in beyond reasonable doubt. But I also suggested that we make lots and lots of decisions every day on balance-of-probabilities-based arguments (“Should I take an umbrella with me? Should I invest in equities?”), and that the demand for beyond reasonable doubt proofs – as eg. demanded by the denialists – was often unrealistic and, frankly, silly.

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gordon 05.15.13 at 1:09 am

Should have been Lee A. Arnold. Sorry.

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Lee A. Arnold 05.15.13 at 1:26 am

Your argument is that we have a high uncertainty whether anyone may fall off a bridge, but this does not prevent us from requiring that bridgebuilders put on railings: So therefore, how can uncertainty be a special problem for climate policy? –The problem is that you are using the word “uncertainty” as a scientist: to name a specific numerical measure in statistics, and its related usage. That is not its original meaning, not its primary meaning, and not its common meaning. For people who are not scientists, which is most of them, the fact that climate effects are distant, or hard to conceptualize, or hidden, is part of the usage of “uncertainty”. You are never going to change this, and most especially you will fail if you begin by lecturing people that they don’t know what they are talking about. On the other hand “preponderance of evidence” is originally the name of a method of argumentation: a rhetorical strategy, by definition.

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Lee A. Arnold 05.15.13 at 1:32 am

Sorry, that last one was to Jerry Vinokurov.

Gordon, yes, we look both ways before we cross the street. I would go with “Nonpredictive Alarmism”.

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Patrick 05.15.13 at 1:43 am

@John Quiggin #171

There has been some decent work on space resources recently, although we’ll see how it pans out.

The NASA asteroid capture mission is a precursor to space resource mining. The moon may not be necessary.
http://www.nasa.gov/topics/history/features/asteroids.html

Planetary Resources(an asteroid mining startup) estimates that a 30 meter diameter asteroid would contain \$25-\$50 billion of platinum. Which is roughly 5 times the amount of platinum that all humans use in a year:
http://www.reuters.com/article/2012/04/24/us-space-asteroid-mining-idUSBRE83N06U20120424

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Lee A. Arnold 05.15.13 at 1:45 am

John Quiggin, yes it is pretty much the same cast of characters. Some people may not know that you can fill a small bookshelf about the rhetorical and scientific strategies of the anti-science crowd, and their political and business connections, and that this has been carried online to SourceWatch and other sites. I just acquired the Oreskes and Conway book, “Merchants of Doubt,” (2010) and it looks like one of the best of them.

By the way, one of the very best papers for the layperson on nonprediction in general complex systems is:

Naomi Oreskes, Kristin Shrader-Frechette, Kenneth Belitz, “Verification, Validation, and Confirmation of Numerical Models in the Earth Sciences,” SCIENCE Vol. 263, No. 5147 (Feb. 4, 1994), pp. 641-646.

It is a gem. There are a number of very different reasons why complex systems cannot be precisely predicted, from the calculational to the cognitive to the philosophical, and it manages to cover a large amount of this territory in a very short space. I’d like to know if there is anything else like it.

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Lee A. Arnold 05.15.13 at 3:35 am

John Quiggin, I am also sorry to hijack your comments thread! In the post you wrote, “If on the other hand, the emergence of intelligent life is common, then the evidence suggests that its disappearance, through processes like nuclear war, must also be common.” …I think this in fact is the case. For example, to pick an earthsize planet close to us, the closest really, and in a habitable range of its star, consider our own sister, Venus. Now, Mars ain’t no kind of place to raise your kid, in fact it’s cold as hell, but life might have started a bit earlier on Venus, and already disappeared… I wish you to note that: (1) Venus’ atmosphere is largely carbon dioxide, (2) it is covered in clouds, and (3) it is around 500 degrees C. on the surface. Therefore I think it may be possible that Venus once had something like the U.S. Republican Party.

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Jerry Vinokurov 05.15.13 at 3:42 am

Some time back, on another blog, I suggested that the distinction is a bit like the legal distinction between standards of proof; â€œbalance of probabilitiesâ€ and â€œbeyond reasonable doubtâ€. I suggested that there was little point in offering a balance of probabilities proof to somebody who was only interested in beyond reasonable doubt. But I also suggested that we make lots and lots of decisions every day on balance-of-probabilities-based arguments (â€œShould I take an umbrella with me? Should I invest in equities?â€), and that the demand for beyond reasonable doubt proofs â€“ as eg. demanded by the denialists â€“ was often unrealistic and, frankly, silly.

Yes, this is a great analogy.

I see the Orseskes book has been mentioned already, and yes, it’s very much the same group of people who are engaged in spreading this misinformation.

The problem is that you are using the word â€œuncertaintyâ€ as a scientist: to name a specific numerical measure in statistics, and its related usage. That is not its original meaning, not its primary meaning, and not its common meaning. For people who are not scientists, which is most of them, the fact that climate effects are distant, or hard to conceptualize, or hidden, is part of the usage of â€œuncertaintyâ€.

Lee, I don’t think that the scientific definition of uncertainty is too far from the folk definition. People can intuitively grasp the concept of some things being more probably or less probably. If I tell you that your house is on fire, it may make some difference whether it’s only your porch that’s caught fire or the entire frame, but you still have to put the fire out.

Ultimately, I don’t think there’s a magic rhetorical bullet here. You just have to persuade as many people as you can with the best evidence that you have, because that’s all there is. The evidence we have right now is more than sufficient to demonstrate the conclusions. My own experience explaining my work (my graduate background is in cosmology) has been that people are actually quite receptive to the discursive modes I’ve suggested above. For example, when I would get asked about what our experiment was trying to achieve (measuring the B-mode of the CMB polarization, for those who care), I would start painting a picture of what we know about the universe and how we know it. I would take care to emphasize that there’s no one magical measurement, but that we can study a variety of different phenomena (the CMB, galaxy clusters, metallicity in stars, etc.) to generate a full picture of what the universe looks like on large scales. I’m no Brian Greene, but I got a very good reception from many different people for that description. I think that the key is to take people’s questions (as long as they’re meant in good faith and not obviously tendentious assholery) seriously and not look down on them. You’re never going to win over the diehard deniers; the performance is for those people who can be convinced if things they don’t know are explained to them. Anecdotally, I have had some measure of success with this method with my own family.

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bad Jim 05.15.13 at 7:07 am

I shouldn’t jump into the middle of such an erudite conversation, but it’s being carried on at such a high level that it misses the sorts of things that sway people. As measured by polls, the popular consensus concerning climate change varies with the weather, swelling in summer and shrinking in winter. A recent study found that many consumers found energy-efficient light bulbs less desirable if their packaging mentioned environment benefits; they were actively hostile towards the idea of taking care of the planet.

Too many of our fellow citizens consider their traditional identity more dependable than facts, which seem to change from week to week. Better education is about as utopian a prescription as atheism, in the sense that there wouldn’t be a problem if this was the cure for it.

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chris y 05.15.13 at 10:03 am

xkcd. Enough said.

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Lee A. Arnold 05.15.13 at 3:29 pm

Gordon @174: Yes, “beyond a reasonable doubt” and “preponderance of evidence” (i.e., your “balance of probabilities”) are the terms for these separate standards for U.S. criminal and civil courts. For example, O.J. Simpson, a U.S. professional athlete and Hollywoodish celebrity, was not convicted of the murders of his wife and her lover by the state in criminal court. So then the relatives of the victims sued Simpson for “wrongful death” in civil court, and won by the preponderance of evidence. The difference in penalties are: criminal imprisonment vs. civil damages, in this case “compensatory” and “punitive” financial damages to be paid by Simpson to the relatives.

However, “balance of probabilities” leads to another problem in the climate policy debate: the denialists can bring in other confusions. What evidence is the judge willing to allow into this court? Well of course, there is no judge. We have total freedom of speech. This has allowed climate denialists to introduce a balancing-weight into the probabilities: i.e., the presumed jeopardy to personal economic freedom, technological development, and economic growth. Of course these are all nonsense — but explaining WHY they are nonsense is a task that is even more complicated than explaining climate science. Why is it even more complicated? Because 1) economics is a complex systems science too, but, 2) it doesn’t have hard inputs like physics and chemistry at its basis; instead you’re meandering into personal preferences and future interest rates, and, 3) economists themselves have been as divided on this as they are about what to do to get out of the current employment slump. So this has been quite a successful tactic to sway the harried and uneducated, and even convincing some people who understand the climate issue: The denialists make a LARGER balance of probabilities.

This sort of thing led me by 1978 to think that a general-systems language that could include ecology and economics in the same picture might be useful in a future where a main problem was going to be, most essentially, that the sheer inundation of complex information would drown environmental policy and destroy the planet. If you are interested, google “ecolanguage” (single word, otherwise you get studies of the prose of Humberto Eco).

I see that Oreskes and Conway have a chapter on freemarket fundamentalism’s strong connection to anti-science propagandists. The authors may have been reading some Crooked Timber discussions years ago.

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Jerry Vinokurov 05.15.13 at 4:37 pm

The Orsekes et al. paper linked to above was interesting, thanks Lee. I think most of the paper is obviously right, and the distinction between verification and validation is a very fruitful one. I have some quibbles with the last section (I think there’s an inconsistency between it and what comes before) and I also think that the authors maybe give too little credit to the power of microphysical laws to scale upward, but it would take a long time to go over that, so I won’t.

I think this interview with Michael Mann is pertinent to the methodological discussion, at least.

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John Mashey 05.15.13 at 5:28 pm

1) See p.12 and then Appendix F. Of PDF at Fake science 2
This includes ~50 thinktanks , most of whom got tobacco money, and some hint of what they promised to do for it. Look up almost any of them in the Legacy Tobacco Documents Library.

2) then the tobacco companies worked with Koch-funded thinktanks to create the Tea Party. See this, on Quarterback Behind the Scenes.

3) As far as I know, Naomi and Wrik weren’t reading Crooked Timber. As to why I might know check Acknowledgements in Merchants of Doubt.

The book’s origins go back to 2004, when she’d done an award lecture that briefly mentioned the abstracts survey. I don’t recall if she proposed doing the 1-page essay for Science or Don Jennedy (then Ed in Chief if Science)asked her, but that got done… And then she started getting hate mail and weird phone calls. Benny Peiser tried unsuccessfully to refute her (with Tim Lambert doing a good debunk of him). In Oct 7 2005 Science she did a book review if Chris Mooney’s Republican War on Science… Fred Singer’s lawyer showed up threatening to sue her and Science. She backed what she said, lawyer disappeared.
By early 2007, she was looking deeper into the Weatern Fuels Asdiciation’s efforts, Singer and the 3 at George Marshall, and speaking on that at places like Stanford. The Monckton/Schulte/Ferguson/SPPI attack on her happened then, trying to redo Peiser, using Monckton’s endocrinologist.

In Sept 2007, she sent me the chapter used for the book proposal to review and the free market theme was already there.

P.250 talks about fact that despite all the talk about free-market, Singer and GMI folks all made their careers on government funding, had very little experience with commerce or industry, and that many business people actually welcome stable, clear regulation.
That wasn’t in the draft, but as a longtime Silicon Valley corporate executive, I observed to Naomi and Erik that it was especially annoying that all these thinktank guys had no clue about real competitive markets.

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Lee A. Arnold 05.15.13 at 8:19 pm

John Mashey, from that PDF you have done a lot of work! I remember you from Tim Lambert’s blog a few years ago. I am sitting here looking at a bookshelf with about 25 books on the anti-science movement just from the last decade. One book that isn’t very well-known, but ought to be, is an analysis of the use and abuse of cost-benefit, risk assessment, contingent valuation, etc., in policy prescriptions for environmental regulation, and the courtroom strategies by the anti-science movement, polluting corporations, and some academics: Sophisticated Sabotage: The Intellectual Games Used to Subvert Responsible Regulation, by Thomas O. Garity, Sidney Shapiro, and David Bollier (Environmental Law Institute, 2004). It is a slim book, 250 pages, but it manages to distill what would have to be a multi-volume history of U.S. environmental law cases.

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gordon 05.16.13 at 1:10 am

Lee A. Arnold (at 184) –

Thanks for the link to ecolanguage.

I have seen a lot of arrogance demonstrated by scientifically literate people trying to explain climate change to others. It’s a huge turn-off for most people, and I suspect does a lot of harm. Back in the days when we were being entreated to “reduce, reuse, recycle”, and the big issue was pollution there was more widespread acceptance of the need for environmental sensitivity and a good deal less patronising exhortation than seems to be the case now.

There was also less threat. Although anti-pollution campaigners, for example, pointed regularly to the negative consequences, there wasn’t “The End Is Nigh!” feeling promoted by current AGW campaigners. Often it comes across as “The world is about to end and it’s Your Fault!” People don’t react well to that sort of thing.

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CJColucci 05.16.13 at 3:19 pm

I’m not sure what would be more depressing: knowing that we’re alone in the universe or knowing (to a high probability) that we’re not but that we’ll (probably) never be able to communicate with our distant neighbors.

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Kenny Easwaran 05.17.13 at 3:03 am

@AndyFromTucson at 160:

“Large complex animals have existed on earth for 230 million years, yet intelligent animals only evolved (approximately) 2.5 million years ago. If evolution always favors the development of intelligence you would expect it to show up relatively soon after complex vertebrates developed. Look at flight: the ability to fly is a very complex trait (so complex human engineers still havenâ€™t replicated the flight of a bird) yet it showed up long before intelligence. The late development of intelligent animals suggests that perhaps it was a fluke, brought about by a rare combination of circumstances.”

Good reasoning but bad numbers. Intelligence only took 230 million years to involve once you got to “large complex animals”. I’m not exactly sure about the definition of “large complex animals”, but if we just put the bound at multicellular life, then we still only take 600 million years.

However, to get from single-celled life to multicellular life took nearly 3 billion years. (If you want to subdivide, it was a billion to oxygen, and then a billion to eukaryotic cells, and then a billion to multicellularity.) But to get from Late Heavy Bombardment to single-celled life was only a hundred million or so. (And if life survived from before the LHB, then that’s still only a couple hundred million since the solidification of the planet.)

So the step to intelligence is harder than the step to flight, but it’s only comparable to the original origin of life, rather than the hard step of getting multicellularity going.

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Kenny Easwaran 05.17.13 at 3:08 am

(It’s possible there’s something I’m missing in that – multicellularity seems to have evolved independently in plants from the evolution that fungi and animals seem to share from slime molds, and as far as I know, the timing is fairly close.)

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bad Jim 05.17.13 at 8:45 am

One of the problems in this discussion is the presumption that humans are the only intelligent life forms on this planet.

As the discussion above has made clear, we are not displaying the sort of competence we’ll need to keep spaceship earth working for the next thousand years, which bodes ill for our spacefaring aspirations.

We have alternatives, though. In her notorious story “The Last Flight of Doctor Ain”, James Tiptree, Jr. described a scientist who devised a pathogen to rid the planet of all primates. On his trip around the world he contemplated a bear, and wondered whether it would be their turn next.

By the way, if you’ve ever wanted to look straight into a grizzly’s mouth, there’s video! (It’s not that much different than being nuzzled by a dog.)

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Mao Cheng Ji 05.17.13 at 9:34 am

“One of the problems in this discussion is the presumption that humans are the only intelligent life forms on this planet.”

Also, the presumption that there is some intelligent life on this planet.

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dax 05.17.13 at 1:11 pm

If you can have the technology where a community of 10 000 people can live in a closed ship over 1200 years, then you have the technology where 10 000 people can live on the moon or Mars without support from Earth. Unless there is a technological breakthrough soon permitting faster-than-light-speed travel, mass colonisation of the moon and Mars will come a lot sooner, say in a couple of generations. It therefore seems more useful to spend our brain cells worrying how we will handle that (and who gets to exploit the resources) since it’s a lot more imminent…

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