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Space Robot Sad Trombone

WARNING DANGER THIS COLUMN CONTAINS PATHOS, ANTHROPOMORPHIZATION, AND RAMPANT SENTIMENTALISM. If that bothers you, turn back now.

I feel a great pathos for robots.

Not just any robots, mind. But explorer robots. Brave little space robots. Voyager and Venera and Curiosity and Beagle robots. Spirit and Opportunity robots, possibly even more than all the others.

I think, honestly, most people do. We personalize the brave little toasters. They have twitter accounts and show up in completely heartbreaking xkcd strips. We root for them, pull for them, and appreciate their triumphs, tribulations, and traumas.

Scientists are still learning new things from images of Jupiter taken by Voyager I in 1979, when I was eight years old.

Eight. Years. Old.

We made a robot the size of a car, and we fired it into space, and it's never coming home. It's going to zoom around out there for-functionally-ever. Someday, a squintillion years from now, when we're long gone, there's a tiny possibility that some other people might find it and stare at it and know that we once existed.

It's a gigantic "Fuck you," to the Drake Equation. It's futile and beautiful, and it matters desperately.

That emotion right there? That thing you just felt, if you are anything like me?

That was sense of wonder.

And that is also what the word "humbling" means.

Brave space robots literally make me misty. And it's not just because they serve as a proxy for the East African Plains Apes millions of miles away, at their controls. In fact, I think most of the time we forget that our speciesmates are back there (back here!) on Earth, fiddling with joysticks and flipping toggles. Or tapping away on keyboards and puzzling over ambiguous shadows in photographs.

We say, "Curiosity discovered--" after all. We even construct gender for her and her and her sister Martian rovers--they're female, a pack of brave, adventurous Girl Scouts out there earning merit badges and drilling in to rocks.

I may have shed a tiny tear when I stayed up way, way too late to 'watch' her land. I was certainly rooting for her with as much ferocity as I've ever rooted for a Bruce Willis character, and considerably more than I could muster for WALL-E. (That'll be my unpopular confession for this column.)

It's interesting to me that we can individually haul up this emotional connection, this strength of empathy, for a machine that--objectively speaking--is just a machine. Not a living creature with feelings and agency; nothing with an object position of its own. More than that, that that empathy is easy for us.

Collectively, we seem to have a hard time summoning that understanding, that complex imagining of the other, for beings who are far more similar to us than these brave space toasters. Who are separated only by a gene controlling pigmentation, or a religious or political belief structure. Possibly it's because brave little robots are so alien. We don't come with any installed stereotypes or unexamined prejudices, and they're not exactly competition. Maybe it's because robots don't have political opinions, or a convoluted and shared history of competition and oppression.

In any case, maybe it's a good sign.

If we can learn to care about robots, maybe we can learn to care about less alien but more strange creatures, such as each other.

176 Comments

1:

Remember that the Jet Propulsion Lab is near Hollywood?

How much of the brave little toaster image is because of the machines themselves, and how much of it is because dozens to hundreds of people have invested a good chunk of their careers in getting those plucky little machines to fly? These people (I happen to know one) are also very good at getting grants to build them, running through the incredibly tortuous bureaucratic maze to get them built, then working together to get them to fly.

And not incidentally, they're also really, really good at PR.

I mean, look at how crazy it is to send a bit of machinery into interstellar space. How does knowing where the heliopause is help us to get to sustainability? It doesn't, but it sure is cool. Makes me misty-eyed too, just as it has since I was eight, and got a tour of JPL from a scientist who'd helped build some instruments on the probe.

But it's still PR.

Here's the question that will help. How do you feel about all those soviet Venera missions? You know, the ones that landed on Venus and gave us the only views of its surface. Are they in the same class as the Curiosity Rover? Why not? Could it be that, just maybe, they didn't get the same PR?

How about all those Chinese missions, or the Indian satellites? Not so sexy, are they, just a bunch of johnny-come-latelies, replowing the ground the US and USSR broke in the 60s? No romance of the rest of the world discovering space?

Or, to be really blunt and cruel, how about all those weather satellites that Congress keeps trying to cancel? They're not romantic at all, they just keep our civilization working by telling us where the storms are, so that cargo ships can route around them and not sink, thereby keeping us fed and supplied with the computers and phones and other junk we need. Those satellites keep our civilization working, yet every few years, NOAA has to go to Congress to beg for funding to keep them working, to launch the next generation as the old birds die. And often they don't get funded. Infrastructure isn't as sexy as cute little explorers, is it?

Why don't we lionize the weather satellites, those tireless guardians of our global civilization? What they do is far more noble than figuring out whether there are methane volcanoes on Pluto. But, of course, I'll be thrilled to see those pictures of Pluto. I'm a sucker for space exploration too.

2:
How about all those Chinese missions, or the Indian satellites?
I'm not sure what Yutu's anthropomorphized Weibo account does to your hypothesis. (Some samples in this article.)
3:

Impressed by Venera (for getting there at all; I realise how tough making things work on Venus is).

Rarely to never see anything about the Chinese or Indian programmes, which is clearly partly the fault of the Uk/USian meedjas.
Similarly with current weather sats, particularly USian ones.

Oh and have the same lack of feeling for WALL-E as Elizabeth does (I bet that surprised her).

4:

I hadn't heard about Venera. Now that I looked it up, it's impressive, but the sense of wonder is undercut by the realization of how damn unpleasant Venus's environment is. It makes Mars look nice, and that's saying something.

P.S. Wall-E didn't do much for me, but his iPad of a girlfriend was actively annoying.

5:

Awwww. I liked WALL-E :)

Anyway, when it comes to anthropomorphisation, you only have to look at the videos of the Boston Robotics "Big Dog" walking robot.

Check your reaction at the 40-second mark in the video :)

https://www.youtube.com/watch?v=W1czBcnX1Ww

6:

Screw Bruce Willis. He's an asshole (right, Arma-shitten - it takes years to make a wildcat driller, but only two weeks to make an astronaut....)

Never cared to see Wall-E

On the other hand... care to join me in singing Witnesses Waltz? And stood on the Florida shore screaming GO! GO! *GO*! as to the few Shuttle launches I saw.

And this is *not* the Real 21st Century, I want the *Real* one back RIGHT NOW, thankyouveddymuch.

mark, wondering where to buy his ticket on PanAm to
the Wheel....

7:

I imagine those aliens would feel something like what we feel when we encounter Oxytricha trifallax.

8:

Let's put blame where it belongs - Bruce Willis was just working with the material he was given. JJ Abrams was the one who wrote that crapsack of a movie.


Also, I'm not sure how anyone can dislike WALL-E. Amazing visuals aside, they told an entire love story with only 2 words. That's an artistic accomplishment all itself.

9:

Don't worry - when we finally get out there big time we will round them all up and put them in a museum.

10:

We read science fiction, so we've been getting rampant sentimentalism for machines for a while. To pick an example that's at hand....

"Do you understand what is about to happen to you?" Amalfi said suddenly.

"YES, MR. MAYOR. WE ARE TO BE TURNED OFF AT ZERO."

"That's good enough." He wondered, however, if they thought that they might be turned on again in the future. It was foolish to think of them as entertaining anything even vaguely resembling an emotion, but nevertheless he decided not to say anything which might disabuse them. They were only machines, but they were also old friends and allies.

11:

I feel a certain kinship with the Voyager probes because we're the same age. I've got a few months on them, but it's like we started our respective lives at the same time.

It's comforting to speculate that, long after I'm dust, these brave machines will still be out there on the journey we set out on together.

12:

I suggest one reason we feel more empathy and interest for the US space probes than Russian or Chinese is the that the US has always been willing to broadcast live. We get to see space exploration as a human endeavour, all the stops and starts, the occasional failures.

The Russian and Chinese governments, basically, don't want other people seeing their rockets explode. So we only hear about them until afterwards. It's the difference between live sport coverage and the next day report.

Better PR? You could call it that. I'd say better storytelling.

13:

Glad it's not just me.

I look upon the stories of Voyager I, and Voyager II [Vger from ST:TMP] with a strange mixture of ineffable sadness and hope for the future.

Nothing is more forlorn than a powerless explorer on a distant planet, and machines are all we have.

I, too, was left strangely unmoved by WALL-E.

Too much pathos?

14:

Also, I'm not sure how anyone can dislike WALL-E. Amazing visuals aside, they told an entire love story with only 2 words.
If you have a complete failure of empathy with the characters, sure you'll not care whether or not there is a "love story"?
I mean I care more for/about a T-800 and I'm both male and straight.

15:

Great post, and I have to agree with most of the comments so far.

The Voyagers, Curiosity, Spirit and Opportunity, Galileo and the other planetary probes have given us "right there" views of places we want to go. The impressive engineering that's allowed most of these robots to far exceed their mission parameters gives us pride in our technological abilities. The non-political scientific goals of the missions remind us that mankind is capable of more than greed, graft and violence. Of course we love them.

I did like WALL-E, even though the movie made him complete the Hero's Journey. All the robots in the movie were clearly AI's, in that they were able to interpret their directives, adapt and in some cases transcend their programming.

Re @14: Paws, Terminator 1 and 2 gave us a great contrasting take on the T-800. The Terminator gave us a thinking machine as a demon, intent on destruction. Terminator 2 turned this on it's head and gave us an AI intent on saving (one) life, and willing and able to sacrifice its own existence to fulfill its mission.

16:

Para 4 - Agreed. I actually started caring about the T-800 in the "damaged endoskeleton" scenes at the end of "The Terminator".

As a contrast, I never cared as much about the T-1000 or the T-X (but this may mean that Arnholt is under-rated as a actor?)

Either way, I think the underlying point is that empathy is at least partly personal.

17:

Hadn't considered Voyageur a robot before. Not because of its box-y design, but because it was always described as a collection of non-integrated and non-interacting bits of equipment.

I've wondered whether Wall-E survived as long as 'he' did because of his pet cockroach ... that is, unlike other machines of his ilk, Wall-E possessed a social/personal capability. (Aw c'mon ... that 'Eva-a-a-' cry was just heart-tugging!)

18:

Minor aside: "Three weeks of training" was one of very few things in that atrocity of a movie which were actually plausible. Vast majority of astronaut training is spent learning various emergency procedures -- what to do when things go wrong. Given the nature of "Armageddon" mission, pretty much anything going wrong means "everyone dies", so there is no reason to spend time practicing for it. All Bruce Willis' crew needed to learn was how to operate the spacesuit and how to work in zero gravity. Three weeks, all of them in the pool, sound about right.

For comparison, when I first learned to scuba dive (PADI Open Water, which is absolute minimum to become a diver), it took 20 hours of classroom and 12 hours of pool. But if all you need is learn to operate the BC and the regulator, and to maintain buoyancy -- with understanding that anything going wrong (regulator free-flow, out of air, sudden current, entanglement, you name it) is just adieu, -- then it can be done in 3-4 hours.

19:

But
"the robots" are our (humanity's) representatives in space, they are our plenipotentiaries to the outer worlds.
They are also part of another human urge:

"There's no sense in going further - it's the edge of cultivation,"
So they said, and I believed it - broke my land and sowed my crop -
Built my barns and strung my fences in the little border station
Tucked away below the foothills where the trails run out and stop.

Till a voice, as bad as Conscience, rang interminable changes
On one everlasting Whisper day and night repeated - so:
"Something hidden. Go and find it. Go and look behind the Ranges -
Something lost behind the Ranges. Lost and waiting for you. Go!"
......

20:

To me these are just machines. They are neuter not feminine. It's the designers, builders and the engineers and scientists who built, launched and then overachieved in operating their necessarily outdated equipment who need our praise and appreciation.
Wall E was clever but a bit pathetic. You don't have male and female robots and love between them is just silly.
I appreciate these probes as much as anyone. I moved house on the day of the BBC Horizon programme on the Saturn encounter and fitting a TV aerial before the programme started was my first priority.
Venera had a very high profile in Britain and Russian probes were often in the news here since Jodrell bank sometimes hacked their results before the USSR was ready to release them.

21:

>Someday, a squintillion years from now, when we're long gone, there's a tiny possibility that some other people might find it and stare at it and know that we once existed.

More likely there is nobody else in our galaxy but us.

The Occam Razor response to the Fermi Paradox is simply: "Alien species do not exist, we are the only intelligent species in our galaxy". And it is looking more and more like we are all alone:

http://io9.com/is-it-time-to-accept-that-were-alone-in-the-universe-1654960619

Lack of metals:

Indeed, life is dependent on the presence of five critical elements, or metals in the parlance of astronomers: sulfur, phosphorus, oxygen, nitrogen, carbon (or SPONC for short). These heavier elements were cooked in nuclear reactions inside stars and became part of the interstellar medium only when stars reached the end of their energy-producing life. So, as time went by, the concentration of metals in the universe gradually increased.

But here's the thing — these heavier elements only recently became sufficiently concentrated in the interstellar medium to allow life to form. Planets around older stars, therefore, are likely to be low in SPONC. Only around relatively young stars, like ours, can life emerge. So humanity would thus be among the first civilizations — perhaps the first — to arise.

Gamma Ray Extinctions:

According to new work conducted by astronomers Tsvi Piran and Raul Jimenez, the odds that a planet could be hit by a GRB depends on its place in space and time. The closer that a planet is to the galactic core, where the density of stars is much greater, the odds increase. Their models show that a planet near to the core has a 95% chance of being hit by a catastrophic GRB at least once every billion years. Pulling back a bit, about half of the solar systems in the Milky Way are close enough such that there's an 80% chance of a GRB per billion years.

But here's where it gets interesting: The frequency of GRBs were greater in the past owing to lower levels of metallicity in the galaxy. Metal-rich galaxies (i.e. those with significant accumulations of elements other than hydrogen and helium) feature less gamma-ray bursts. Thus, as our galaxy becomes richer in metals, the frequency of GRBs decreases. What this means is that prior to recent times (and by recent we're talking the past 5 billion years or so), GRB extinction events were quite common. And in fact, some scientists suspect that the Earth was struck by a GRB many billions of years ago. Piran and Jimenez figure that these events were frequent and disbursed enough across the Milky Way to serve as constant evolutionary reset buttons, sending habitable planets back to the microbial dark ages before complex life and intelligence had a chance to develop further. Fascinatingly, before about 5 billion years ago, GRBs were so common that life would have struggled to maintain a presence anywhere in the cosmos (yes, the entire cosmos).

The Rare Earth Hypothesis:

One of these resolutions is the so-called Rare Earth Hypothesis — the suggestion that the parameters required to spawn a space-faring species is excruciatingly narrow. It's an idea that was put forth in 1999 by paleontologist Peter Ward and astronomer Donald Brownlee. By synthesizing the latest findings in astronomy, biology, and paleontology, the two put together a list of variables that, in their opinion, make our planet exceedingly rare in the cosmos. So rare, in fact, that it may explain why we may be the only ones out there.

Rarer Civilizations

It's also possible that life is exceedingly prolific in the universe, it's just that civilizations are what's rare. As Webb points out, it's not a given that tool making species are common, or that technological progress, the advent of complex language, and the adoption of the scientific method are inevitable.

Rarest Technology

The high likelihood that most Goldilock Zone water worlds are WETTER than Earth and hence unable to evolve hands-and-fire sapients like us. Ther may be intellegent cetacians and cephalods, but their water worlds would prevent fire and technology from being invented.

22:
The Occam Razor response to the Fermi Paradox is simply: "Alien species do not exist, we are the only intelligent species in our galaxy".

Not really. The Fermi Paradox is a load of bollocks. I really have no idea why it gets the namechecking it does

23:

For comparison, when I first learned to scuba dive (PADI Open Water, which is absolute minimum to become a diver), it took 20 hours of classroom and 12 hours of pool. But if all you need is learn to operate the BC and the regulator, and to maintain buoyancy -- with understanding that anything going wrong (regulator free-flow, out of air, sudden current, entanglement, you name it) is just adieu, -- then it can be done in 3-4 hours.

Yep. When I learned it was ten weeks one night a week. First 3 weeks were spent learning to almost drown and still come up and swim with mask fins and snorkel. Then 7 weeks of basically the same thing with the scuba gear. How to do things when everything working was a few hours and easy. I still have memories of drinking half that pool. And with the dive computers they have now...

24:

"More likely there is nobody else in our galaxy but us."

We are speculating with essentially none of the information we would need to make an informed guess.

Like, our life uses metals wrapped in organic compounds to catalyze chemical reactions in water solution. Presumably we evolved to use the metals that were available to us. Is that the only way to get "life"? We don't know, we only know about the one example we have, and we don't know about any place that we can be sure has no life. We have a handful of examples that we can be sure do not have life that depends on chemical reactions in water solution.

We do not know which kinds of life would be resistant to gamma rays.

Our own world has no land higher than .15% above sea level, so it seems plausible that if things were a little bit different we would have no land above sea level and many planets with water would have none. But we don't understand these things very well at all. And of course beings on water worlds could not make fire any more than we can make chlorofluorocarbons or plasmas, but maybe they wouldn't need to.

The laws of physics may prevent any significant travel between stars, or maybe they don't. What we think we know about the laws of physics may be approximations that work reasonably well in some circumstances.

If they can come visit us, why haven't they announced themselves? Maybe we're just lucky so far. Or maybe they did, say 200,000 years ago, they might have come in and taken all our niobium and made us mine more until there was no more high-grade ore, and then they smashed our civilization and left. Nobody will come here for niobium for a long time because they know it's already gone, but maybe somebody will settle for gold. We could make up stories all day.

We simply do not know enough to draw conclusions or assign probabilities.

But there's this -- when I was a kid one of the arguments was that probably very few suns have planets, and life can't evolve without a planet. They guessed (without a lot of evidence I could see) that only about one star in a thousand or ten thousand would have planets. But now we believe that many stars have planets, so the probability that there are starfaring aliens has gone up a lot in just a few decades.

25:

I think the Fermi paradox is a useful starting point for questions. What is a load of bollocks is the Drake equation.

26:

Daniel Duffy @21: Ah, so the only kind of life which could exist is life as we know it. Right. And the only kind of intelligence which might be out there is something analogous to human intelligence. There are no other options...

Except...

Except, we don't know that those metals are a necessary pre-condition for all forms of life. We don't know that the forms of life we have here on this planet are necessarily even typical of what's possible out there. All we know for certain is that this world works for us.

Why aren't we meeting the neighbours, so to speak? Well, let's start from what we know about space: it's BIG, and we haven't even begun to map out all of it yet. We have a universe so vast light (the fastest thing we know) takes centuries and millennia to traverse it. The next thing we know about space is that it's expensive to get to - we're using stored energy from prehistoric plants in order to fuel our short-range rocket journeys to low-earth-orbit, and that fuel is fast running out. Predictions are by the time we reach the 2060s, we'll have well and truly run out of fossil fuels, and we'll be back to an energy economy which is limited by and to the amount of energy we have incoming from the sun here and now, once more. So the "window" for our space race is probably going to be less than a century. The debris of the space race could well become the pyramids or Stonehenge of our era - something we leave behind, for latter generations to wonder about what the fsck we were thinking when we built it.

Assuming we're typical for a dominant species (curious about what's out there, willing to pollute our wider district with all our radio transmissions and so on), it's highly likely the reason we haven't heard from the neighbours, so to speak, is because either a) we weren't listening at the right time (if their "space race" transmissions peaked back in the 17th century, we'd have missed them entirely by the time we had the technology to listen for them in the 20th) or b) we're talking, but they can't hear us yet (because they're not due to "peak" into the sorts of technologies which can start to make sense of radio waves until what we'd consider the 25th century - by which time our transmissions may well have passed them by.

If we're atypical - if the typical species out there is fairly insular, not interested in wider exploration, and quite content to remain at home, then they may never have been listening at all.

(There's also the whole "not all intelligence is going to be human intelligence" proviso, which means they may not have been communicating in ways we'd consider "communication". If they're sending transmissions in coded infra-red or ultra-violet pulses of light, how are we going to know about them when we're listening for radio waves? How would we recognise a transmission from another, non-human, intelligent species anyway? How would we distinguish it from the background noise of the universe? We thought we had something, back when we were getting freakish pulses of radio waves back in the fifties - then we discovered it was a natural phenomenon, a pulsar. So if we start getting pulses of radio waves from our neighbours who happen to be in the same general direction from us as a pulsar, how are we going to tell?)

We already have analogues for this experience in our own history. The ancient Greeks weren't there for the building of the Pyramids, so their stories about them were guesswork and half-understood stories from Egyptian traders. The Romans didn't have the faintest clue why the ancient people in Britain built Stonehenge (and the guesses that it might be a temple are just that - guesses). Modern Australians really don't know what the oldest indigenous rock art is supposed to be a representation of - or if it's even supposed to be a representation of anything at all. We don't know because those civilisations peaked and declined before their successors came along, and what we're doing now is trying to reconstruct their context from our more modern one. All we know for sure is that it took work, it took labour, and these sorts of monuments are usually a monument to surplus and prosperity.

27:

I think this XKCD What if? entry pretty well answered the Fermi Paradox. The big problem is that we assume that we can actually detect alien civilizations if they're like ours. In truth, if we were on Alpha Centauri, we'd have trouble detecting Earth's broadcasts with our present technology on both the sending and receiving ends. Even if the galaxy is full of technological civilizations (which is dubious), simple physics may keep us from hearing each others' radio frequency broadcasts, just as it makes it very difficult (probably impossible) to fly between stars to visit each other.

28:

Heteromeles @27 - exactly! If there was another civilisation which was exactly like ours, advancing in technological lock-step with us, on the opposite side of the galaxy to us... how would we know?

Really, the Fermi paradox consists of the equivalent of someone looking out the window on a quiet suburban street for twenty seconds at two am on a Sunday, and positing that because they can't see any children playing outside, there's nobody else alive on the planet. I mean, yeah, that's one interpretation of the data...

29:

>Ah, so the only kind of life which could exist is life as we know it.

Not exactly, but it would have the follow the same universal laws of chemistry, physics and energy that we do. For example, basic chemical bonds won't survive GRBs. Which means complicated life of any kind won't either - not matter what it is made of.

>we don't know that those metals are a necessary pre-condition for all forms of life.

We're free to imagine different life chemistry - and they could probably now be simulated by computer models. But you will probably already find them here on Earth.

For example, some animals do not have hemoglobin to carry oxygen through the blood. Crustaceans (shellfish like lobsters, shrimps, and crabs) use a compound called hemocyanin. Hemocyanin is similar to hemoglobin but contains copper instead of iron. Many copper compounds, including hemocyanin, are blue. Therefore, the blood of a crustacean is blue, not red.

(Sorry Mr. Spock but your green copper-based Vulcan blood should actually be blue.)

We can imagine life based on infra red photosynthesis (but not ultraviolet - the wavelengths are too long to be intercepted by cells) on moons orbiting brown dwarfs that give off heat but not light. And if brown dwarfs greatly outnumber suns, then visible light spectrum based life may be the exception instead of the rule. But green sulfur bacteria on Earth already uses infrared.

The fictional planet Darwin IV in Wayne Barlow's book "Expedition" evolved life that used sound exclusively instead of sight. Earth has similar creatures. They're called bats.

All we can expect are variations on a theme. The laws of physics and chemistry place limits on what elements could be assembled and function as "life". Truly exotic combinations and chemistry don't work here on Earth and most likely won't work anywhere else because of these same laws - you can't reasonably expect plutonium based blood or triple helix DNA (which is chemically unstable).

As for missing the window of opportunity for talking with alien species, the Fermi Paradox is actually based on a more blunt observation. Even if there was only one alien race in the entire galaxy that built self replicating Von Neuman machines their probes should have filled the galaxy by now. "Windows" don't matter. We would not have to know when to listen or where to look.

If intelligent alien species existed their space craft should be in orbit above us already.

30:

If intelligent alien species existed their space craft should be in orbit above us already.

Like ours are in orbit around their world?

31:

>Predictions are by the time we reach the 2060s, we'll have well and truly run out of fossil fuels, and we'll be back to an energy economy which is limited by and to the amount of energy we have incoming from the sun here and now, once more.

Not going to happen. We are never running out of oil.

Though in the future, extracting oil from the ground will be as obsolete as extracting oil from whales:

http://www.businessenergy.net/DE/Articles/Natures_Own_26651.aspx

32:

If intelligent species existed in large numbers her must be civilizations far older and more advanced along the Kardeshev scale than we are. Such a civilization would fill the galaxy with Von Neuman probes in a relatively short period of time.

But GRBs would have snuffed out any million year old civilizations before they had a chance to start.

33:

Daniel, I'm going to ask one small question (it is relevant) regarding this comment:

We are never running out of oil.

and it's attached article.

Have you ever done any gardening at all?

34:

"Such a civilization would fill the galaxy with Von Neuman probes in a relatively short period of time."

It's possible that life in our solar system evolved from their Von Neumann probes.

"But GRBs would have snuffed out any million year old civilizations before they had a chance to start."\

It sounds like you know a lot more about the technology available to a million-year-old civilization than I do.

For all I know an advanced civilization might think of a GRB as an energy source that could be tapped.

I am just not convinced that we know all that much, yet. We probably don't know about all the ways to implement life, and there are things about physics and chemistry we don't know yet, and we don't know much about the inevitable constraints that must limit every advanced civilization that knows more physics, chemistry, and technology than we do. So I think it's premature to be confident in our predictions about such things.

But if you feel confident then go ahead, it isn't all that likely that your conclusions will be disproven (or tested) in your lifetime.

35:

"Such a civilization would fill the galaxy with Von Neuman probes in a relatively short period of time."

Even if that conclusion was true (and I'm not convinced at all - space is still big), how would we even know they were there? A probe would not need to be large or noisy, space is big, and even in the space around our planet (where we have only been for a few short years) there's a vast quantity of junk.

Here on Earth we have covert surveillance tech that escapes detection all the time, even when we're looking for it and even when we know it's likely to be there - and that's with very primitive technology that is at least decades from any self-replicating VN space vessels. Hell, we've got foreign-owned orbital satellites that we can actually *see* that still hide their secrets from observation. A putative VN probe could be the size of a matchbox, and almost by definition it would use tech we would not know to look for (and might be unable to detect). Your thesis actually requires that this hypothetical civilization would not just have such probes (and have them everywhere), but would also want to draw attention to them.

36:

Actually...

It's be interesting if someone with enough physical chemistry could do the calculations, but I can imagine that universal VN probes could be technically impossible. Obviously such probes would need to be robust to very widely varying environments in order to be able to obtain the materials for their own replication. I can imagine that even with a nanotech-type manufactory the shielding requirements would create mass issues that might make such devices unworkable - the larger the mass of the device, the greater the material requirements for replication, and hence the greater the need to enter environments with greater hazards, hence the greater the need for shielding, hence the greater the mass... And if such a device was caught in a space object's gravitational field, it would run into new problems with fuel requirements... Not something I've considered before, this is just a random thought. I thought I'd throw it out there for the mob to rip to shreds. ;)

37:

I have a few questions that might shed some light on this debate.

1) If the death star blew up a planet tomorrow within our stellar neighborhood, would we see it, or find out about it?

2) Why would any civilization build Dyson Spheres? Don't get me wrong, on paper they're a great technology. However, I think mining their star would be a much more sane proposition. Heck, even moving their gas giants closer to their star might make more sense. After all, think how valuable the ion flow between Jupiter and Io is? Would they even need all that energy? For that matter, is there even enough mass in the Solar System to build a Dyson sphere?

3) Why would anyone build von Neumann probes? I mean, VN probes make a lot of sense if you're going to start colonies around other star systems. Unless you have VERY high birth rates, I don't think colonization would happen that fast. Exploration, maybe. However, probes to conduct exploration would be small enough that we couldn't detect them unless their in Earth Orbit (example: It is estimated we only found 5% of sub-50 m. Near Earth Asteroids. With a wealth of planets in the galaxy, an individual star system would have the value of Campbell Island in New Zealand (I just drew up a random uninhabited island). I mean, we could colonize it if we wanted to, but why bother? The lack of colonization of the island might have been considered wasteful by a 18th century explorer. Priorities change.

4) Why would other civilizations be as wasteful as we were in the 20th century with radio waves. Heck, we've reduced radio pollution by 2/3, according to some sources I read about in my undergrad. Further, space probes are moving towards laser communication due to the high data transfers required.

38:

My opinion on the Fermi paradox is that it has become a Rorschach test. For people who live in a cold war or a war, civilizations wiped themselves out in nuclear war. People concerned about global warming or peak oil believe civilizations destroyed their environment or used up their "easy to get" resources. People who are terrified of their government or of a potential theocracy would say that most civilizations are trapped in a dictatorship or a theocracy. Don't get me wrong, I think some of these fears are legitimate.

My personal theory is that most hypotheses of solutions to the Fermi paradox true. There are millions of ways for a civilization to fail, sometimes before it even starts. Without knowing the facts on the ground, applying Occam's Razor is useless.

At least we removed the rare planet hypothesis recently.

39:

And, at least for certain types of dictatorship (includes evengelising theocracy), interstellar expansion is a Good Thing anyway.

40:

At least we removed the rare planet hypothesis recently.

Indeed so. I've been playing Elite: Dangerous, and it amused the heck out of me that one of the recent patches was updating the planet count round a couple of stars where the game had guessed wrong. When I'm making a transit, and I come out of jump next to a star and there isn't anything else in the system, I now start wondering how in the name of whatever it managed to be that tidy.

The proposition that (a) it is possible for intelligent life to have evolved within this galaxy, but (b) it could only happen the once seems to me against Ockham's Razor. The first part appears proven (I leave open the faint possibility of cross-multiverse spawning), but I can't think of anywhere else in science where endlessly repeating the conditions that have led to success cannot lead to anything but failure.

41:

The Drake equation was an agenda.

Its treated my many as this huge insightful thing. When Frank Drake originally wrote it down, it was on a blackboard at the start of a meeting on SETI. Its an example of a Fermi problem (http://en.wikipedia.org/wiki/Fermi_problem) and would have been instantly recognised by the attendees as such.

That is, the equation in itself is no great insight (and several terms could be criticized or redone), but to make progress we need to have values for the terms within it.
Such as the number of planets per star, the number of habitable planets, etc.

42:

If any civilization went the whole Transhumanist hog they would have converted the whole galaxy into computronium within 10 million years. So, we don't see that. The Fermi Paradox might tell us that it has happened and we have our own reservation all to ourselves inside a tonne of the stuff where Earth used to sit a billion or so years ago.

As for robots and emotions, it is less important how we feel about them than how they will eventually feel about us, if we don't want to end up as either hitech roadkill or a minor pest control problem for AIs.

43:
The proposition that (a) it is possible for intelligent life to have evolved within this galaxy, but (b) it could only happen the once seems to me against Ockham's Razor.
The intersection of the Fermi Paradox and the Drake Equation is the Great Filter - the idea that there's a reason we're not constantly bumping into starfaring aliens. It's an idea with a perverse consequence: that we should be hoping for life to be rare as possible. As the terms towards the left of the Drake Equation go up, so does the likelihood the Great Filter is something we've yet to meet, rather than something we've already passed. So those who contend the universe is empty of other life are the optimists!
44:

>Even if that conclusion was true (and I'm not convinced at all - space is still big)

Actually its remarkably easy for a civilization to explore every star in the galaxy with VN probes, and it can be done in a relatively short time period:

http://io9.com/it-s-easier-for-aliens-to-visit-us-than-previously-thou-909418813

A new study suggests that by using the slingshot effect to propel self-replicating probes through interstellar space, an advanced extraterrestrial civilization should be able to visit every corner of the galaxy in a startlingly short amount of time. The Fermi Paradox, it would seem, is alive and well....

And based on the sophistication or purpose of the probe, it could establish colonies on suitable planets (either by spawning biological organisms or robots imbued with either AI or uploaded minds). More simply, an SRP could spawn Bracewell communication probes, which could make contact with a resident (or future) alien civilization.

And indeed, the power of the SRP lies in its ability to replicate at an exponential rate. The initial rate of exploration would be slow, but after producing potentially millions upon millions of offspring, the rate of expansion would increase by an order of magnitude. So even at a speed of about a tenth the speed of light, these probes could cover a huge amount of territory in a relatively short amount of time from a cosmological perspective...

But according to the new study, which was published in the International Journal of Astronomy, aliens (or future humans for that matter) could use the the slingshot effect to propel SRPs from star to star. And in fact, this is precisely the same phenomenon that was used to move the Voyager spacecrafts through our solar system as they hopped from planet to planet. But for it to work on a galactic scale, the SRPs would use slingshot maneuvers around stars, gaining a boost in velocity by extracting energy from each star’s motion around the galactic center.

These maneuvers would carry little-to-no extra energy cost. And, as shown in previous work, a single Voyager-like probe exploring the galaxy could do so 100 times faster when carrying out these slingshots than when navigating purely by powered flight.

“[The] parent probe reaches the new destination star, and before it slingshots around the star it releases the replica probe,” they note in the study. “Both the parent and replica use the slingshot to boost their velocity. As the velocity boost from a slingshot trajectory depends on the angle between the stars, the parent and the replica will achieve different velocity boosts as they will have different destination stars.”

The researchers put this model to test by using a computer simulation. What they discovered was that, by using this technique, an alien civilization could send probes traveling no faster than 10% the speed of light to every single solar system in the galaxy in only 10 million years. Which is incredible — that’s an amount of time that’s significantly less than the age of the Earth.

This means that an alien civilization could (and should) have arrived in our solar system by now. So where are the probes? Or the colonies?

The grim possibility is that we’re alone, and no alien civilization exists to send out the probes. But that’s weird and highly improbable given that intelligence could have emerged in our galaxy about 5 billion years ago.
.
.
.

So unless the alien VN probes are hiding from us like the Monolith in Kubrick's "2001" we are alone in the galaxy. If the VN probes don't exist, then neither do alien civilizations.


45:

>It sounds like you know a lot more about the technology available to a million-year-old civilization than I do.

That's not my point. My point is that pervasive GRBs would have snuffed out any advanced life forms before they evolved intelligence let alone developed the technology that could harness GRBS as an energy source as you suggest.

Sorry Cthulhu fans, there are not Ancient Old Ones. If there are any other intelligent species out their they would have evolved fairly recently and at about the same time as we did.

Here is a wild idea:

WE are the "Ancient Old Ones".

Our purpose as a species is to spread intelligent life throughout the galaxy and we seed the universe with our kind.

A solar sail about the size of Colorado (and being only one carbon atom thick) can use the pressure of sunlight alone to accelerate a payload to between 0.01c to 0.1c. Deceleration can be achieved by the pressure of sunlight from the destination star. No expensive fuel or engines needed for this cheap and slow approach. So it would take decades or centuries to reach a nearby star, what’s the hurry? The payload would consist of millions of frozen embryos that are thawed out and brought to term in a artificial wombs. The first generation of colonists would be raised by android “mom” and “dad” analogues programmed to care for, protect, educate and nurture the children (“watched over by machines of loving grace”). After establishing a colony, the space ship utilizes local asteroid resources to build more solar sail ships and payloads, sending them off to more stars where the process is repeated over and over again...

... until we are a galactic species immune to extinction.

I am reminded of an SF story where mankind has spread across the galaxy pushing both clockwise and counter-clockwise around the galactic center along the various spiral arms of the Milky Way. This continues at sub-light speed for 100,000s of years until we finally get to the far end of the galaxy at the opposite side from Earth. There our latest colony finally encounters another intelligent alien species.

After much confusion and threats, we finally realize that the "aliens" are us. They are humans who have migrated the opposite direction around the galaxy, with evolution and genetic engineering changing them to survive on 10,000s of alien worlds with different environments. By the time both branches of humanity meet on the opposite side of the galaxy, neither is recognizably human any more.

46:

I usually kill my wife's plants.

So I am forbidden to do anything except mow the lawn.

47:

>At least we removed the rare planet hypothesis recently.

The Rare Earth Hypothesis is not the same as rare planets. REH is a series of filters that make planets containing intelligent life extremely rare no matter how many planets there are to start with. REH states that life at the bacterial level may be commonplace throughout the galaxy, but there are so many fluke/chance occurrences that make our existence possible that other intelligent species are rare to nonexistent.

48:

You make a good point. There really is not rational cost effective reason for human exploration of space.

As much I would wish otherwise, there is just no financial, scientific or defense justification for a large sustained human presence in space. Defensive spy sats, weather and comsats, robot planetary rovers and orbital probes do the job just fine. No human need apply. From a purely "bean counter" point of view, even the international space station is already a white elephant.

Fortunately life isn't about bean counting, or even solely about maximizing profit. The spirit, elan and morale of a society are at least as important as its material wealth, perhaps more important. I'm old enough to remember being thrilled by blurry black and white, live TV images of men walking on the moon. Apollo was primarily about non material things like national pride, prestige and patriotism. However as the world becomes closer and borders blur, such chest thumping patriotism may go out of fashion, and won't provide the impetus for further efforts in space. Maybe Chinese taikonauts will provide the same goad as Russian cosmonauts, but more likely future space missions will be multi-national, cooperative efforts.

In its mystical aspect Apollo embodied the spirit of its age. Every so often in history, a civilization rises up and uses its accumulated economic surplus to create something which has no practical value (from a bean counter's point of view) yet is absolutely essential to the morale and spirit of its people. The Egyptian pyramids and Gothic cathedrals are two examples. The Saturn V rocket in many ways was our Notre Dame or St. Peter's. IMHO we have lately become so mono-fixated on economics that we have forgotten that it is the intangibles which make a civilization great. "Without a vision, the people perish" — I believe both secular humanists and devout theists can agree on that.

A comparison between the Saturn V rocket and the Gothic cathedrals or Egyptian pyramids is an apt analogy. Perhaps, just perhaps, religious faith might provide the necessary spark for a renewed effort in space — and not just because many Apollo astronauts experienced a profound religious awakening while in space and on the moon.

So why not a "faith based" space program? How about founding another "shining city on a hill", this time on the Moon. Why not "touch the face of God" from orbit? How about a "new Jerusalem" on Mars, free from the corruption and immorality of the Old World? As crazy as this may sound, we made need to harness the same motivation which built the cathedrals and pyramids to send humans back into space.

When it comes to the long term survival of our species, rationality may be over rated. Since there may be no rational reason for man in space, we may need an irrational reason.

49:

I know that. That's why I called it the Rare Planet Hypothesis, not the Rare Earth Hypothesis. When I was growing up, there were several hypotheses which stated that planets were rare. Those no longer exist.

As for financial reasons to go into space, the only one that makes sense so far is space tourism. Of course, that is limited to the Earth-Moon system (and Near Earth Objects). Of course, it only makes sense for the very rich, at least right now.

50:

That is so far from what I said that I am having difficulty recognising it as a related argument! All I said was that "being a dictatorship" is not a 100% guaranteed barrier to wanting an interstellar space program, and that certain types of dictatorship might even view one as desirable.

51:

Sorry for misunderstanding. But when you emphasized "evengelising theocracy" it implied a religious jihad or crusade as the motivating force behing human colonization of space.

And IMHO if such an irrational impulse can result in something as majestic as a gothic cathedral or great pyramid, we should harness a similarly irrational motive to get us off this rock.

52:

Ok, I see what you were thinking now; all I meant to do was include a Pastafarian priesthood ordering the convertion of the green-skinned, blue-blooded natives of the Greater Magellenic Cloud to worshipping the Flying Spaghetti Monster (all hail his noodly goodness for ever and ever ramen) as a subset of dictators.

I'm not saying that this is "the right thing to do" or even a Good Thing, except insofar as it supplies a motive for doing the engineering (Stephen thinks that there is a hole in Einsteinian Relativity that you can fly a warp-drive starship through: If he's right then all that remains is engineering).

53:

"My point is that pervasive GRBs would have snuffed out any advanced life forms before they evolved intelligence let alone developed the technology that could harness GRBS as an energy source as you suggest."

We have only one data point to work with -- GRBs have not snuffed us out before we evolved intelligence.

Though they might snuff us out any second now. Three -- two -- one -- whew. Not yet.

We don't know how long it will take us to develop the technology to be reasonably safe from GRBs. We learned a whole lot between 1800 and 1900 -- especially we got Maxwell's Equations which provided a complete explanation for electromagnetic radiation. (They thought.) We learned a whole lot between 1900 and 2000, especially we got relativity and quantum mechanics in the early part of the century, and it seems like we've been floundering ever since. What new physics will we learn in this new century?

Right now the easiest way I can see to be immune from GRBs is to evolve inside a star. I don't know how life would start there -- it surely wouldn't involve organic chemicals in water. But I don't know much about the inside of stars, certainly not enough to say that there couldn't be life there. They'd have an immense gravity well to get out of, if they wanted out, and interstellar space would be a lot colder for them than for us. But those are minor problems of technology. Anyway, the inside of a star would provide a whole lot of shielding against GRBs. ;)

I just don't know much. I can imagine lots of possibilities that I don't know how to rule out.

54:

>We have only one data point to work with -- GRBs have not snuffed us out before we evolved intelligence.

The point being is that we (and life in general throughout the galaxy) could only evolve after the age of pervasive GRBs. As such there are no Ancient Old Ones, no alien civilizations millions of years old.

55:

Hear, hear - I wholeheartedly agree! Even if the space program grew out of an origin in Nazi vengeance weapons (and made great use of their scientists), even if Apollo was just a way to show up the Soviets, it became something greater, more inspiring. If there's anyone who watched the Eagle landing and wasn't moved, I don't want to meet them. That memory is indelibly etched in my mind.

Von Neumann probes, the Fermi Paradox, the Drake Equation and the Great Filter each contain so many assumptions about the nature of other civilizations as to be essentially useless except as thought experiments or polemics - just because a civilization can make self-replicating probes doesn't mean they think it's a good idea, nor is it inevitable that a different civilization will have a desire to explore the galaxy. What if they are fervent believers in Fred Saberhagen's Berzerkers, and spend their time NOT emitting radio signals? What if they develop laser communcations before radio? What if they have relatively long lives/practical immortality and reproduce very slowly? There are just too many imponderables to make any conclusions. We have only a lack of communcation so far. You can't prove much without data. We've been emitting radio waves (at rapidly reducing power levels and higher frequencies) for barely over a century. Even if those signals were/will be heard, there's no guarantee another civilization will want to respond, or they could be 250 light years away and still not have heard the Shadow or seen Lucy and Ricky.

re @45: We could indeed be the Old Ones. We could also be the badasses of the galaxy, faster, stronger, and more violent than any species that survives long enough to travel between the stars (if that travel is possible). There's only one way to find out.

As to why leave the planet, I'll drop a link to one of my favorite moments in Babylon 5:
https://www.youtube.com/watch?v=xkj2lR9CT08

56:

I once met a medication delivery robot named Tug. Despite being literally a cube on wheels, he was adorable and I immediately felt empathy for him. His job was not exploratory; it was menial -- he delivered medication from one part of the hospital to the other. Instead, I think my empathy for him was because of two things: he moved in an animate way (he fluidly avoided running into people in the hallway, and if you approached too close he'd fluidly move back -- like a curious animal) and he asked for help (specifically, he politely asked me to open the door for him).

(This is a machine similar to the one I met: https://www.youtube.com/watch?v=sMGENBEhYTM)

57:

Which led me to think of http://en.wikipedia.org/wiki/St_John%27s_Hospital,_Livingston . There's no mention of them in the Wikipedia, but it is quite extensively robotised for functions like drugs, laundry, and patients' meals transport, although the robots apparently use a separate corridor system to staff, patients and visitors to you'd not get that sort of empathic exchange.

58:

"The point being is that we (and life in general throughout the galaxy) could only evolve after the age of pervasive GRBs. As such there are no Ancient Old Ones, no alien civilizations millions of years old."

That would be true if the only way to get life is with covalent bonds on the surface of planets. (Because gamma rays can produce free radicals that can damage organic molecules, and the surface of a planet doesn't provide enough protection.) And we must assume there are no suns with suitable planets among the suns spread out thin enough on the edges of the galaxy to not get clobbered.

But I think you have confused millions and billions. In the grand scheme of evolution we don't know of any reason why intelligence could not have evolved on earth well before a million years ago. Maybe it did. Our main evidence that there was not a grand more-or-less-human civilization a million years ago is that we have some fossils of nonhuman primates who used fist-axes from that time. Surely if there was a civilization they wouldn't have let those primates wander around! Also, they left a whole lot of silver lying around on or near the surface of the earth, and they left all that coal and oil unburned.

If there are other civilizations there's nothing to keep them from having a tiny edge and being a mere few million years ahead of us, unless we assume that civilizations always fail pretty quick and can't last for millions of years.

59:

A thought on the Fermi paradox, Once an alien race became star-faring and space-adapted (If such a thing is at all possible) what further use would they have for planetary surfaces? For all we know, there could be a galactic federation Oort settlements, our invite pending on being able to fly out for a visit. Very early to say anything definitive yet.

60:

Always liked the Fermi Paradox, and the basis it seemed (seems) like a department of "the bleeding obvious". Never had much patience with objections to it; if you are positing a populous cosmos. Because either all aliens chose not to investigate the cosmos, presumably for differing reasons even given presuming radically different evolutionary histories (bit of a co-incidence?) or otherwise assumes a uniformity of behaviour, if not motivation, that seems unlikely.

In a way the Fermi Paradox reminds me that the truth of my atheism is proved by the fact of my atheism! In as much as there are no Omniscient, Omnipotent, all-loving Gods who want me to know they exist where there is a downside to not acknowledging their existence (Hell!)! Because if there were, the fact of their (Her) existence would be a brute fact like gravity or beer, and similarly undeniable.

Which seems far too easy. There must be a problem with my thinking (and not for the first time!).

As a matter of interest, my Kitten goes mad about 4am, and savaged my right ear this morning. Despite feeding on my blood (blud?) some cat food reduced the madness. Off to the vet for inoculations in 5 min. And advise about passports for pets.

61:

In a way the Fermi Paradox reminds me that the truth of my atheism is proved by the fact of my atheism! In as much as there are no Omniscient, Omnipotent, all-loving Gods who want me to know they exist where there is a downside to not acknowledging their existence (Hell!)! Because if there were, the fact of their (Her) existence would be a brute fact like gravity or beer, and similarly undeniable.

Because ants realize that we are their Gods?

62:

Read about a paeds hospital that's getting MEDi (Medicine and Engineering Designing Intelligence) robots to distract kids during blood draws and inoculations. Apparently perceived pain is reduced by about 50% when kids are engaged/distracted by these bots.

63:

Hi David,

Because ants realize that we are their Gods?

Hardly a good analogy: Am I omniscient and all powerful with respect to ants? Do I love ants, to the extent I would sacrifice myself for them? Certainly I am greater than ants in many respects, but hardly a God in any meaningful sense.

Your objection from relative insignificance ignores the alleged "all loving" nature of certain posited Deity s in theistic religions.

Like the Fermi Paradox "the proof of the truth atheism from the fact of atheism" is simple but surprisingly powerful. I must tell Giles Frazer, and possibly the Pope! But may wait until tomorrow.

The kitten survived its first vet venture and may not continue to feast upon human blood, if it is fed last thing, so I am told. No doubt we shall see...

64:

[ Just back home, jet-lagged to hell]

Actually, I prefer to look at SETI from the other end ...

Assume we KNOW that there's an alien civilization of roughly our tech level with interesting stuff to chat about 50 light years away. Just HOW would we communicate with them?

Incoherent omnidirectional radio broadcasts of prime number sequences are not the way we'd do it. Rather, think in terms of bloody great lasers -- but only powerful enough to be detectable with optical interferometry at a 50-500 light year range; no need to be audible at 500-5000 ly). Modulate them with different frequencies: a low-bandwidth simple signal, possibly AM, indicating how to decode the high-bandwidth high-bit-rate signal (packetized, compressed, on a wavelength-multiplexed carrier, maybe). The simple "FAQ" signal can take a long time to send (seconds per bit, kilobits to megabits in size) and repeats continuously; the high bandwidth signal will look like white noise to someone who doesn't know how to receive it and it won't be full of repeats (except maybe frame headers saying "start decoding here"). Oh, and it would help if the low-bandwidth FAQ signal turns to mush once it goes much past the intended recipient.

Am I making sense?

65:
I once met a medication delivery robot named Tug

That's great. I wonder if a less formal drugs regime could be delivered to an arbitrary location?

66:

For example, basic chemical bonds won't survive GRBs. Which means complicated life of any kind won't either - not matter what it is made of.

Wrong.

AIUI the hypothetical pathway by which GRBs kill life off is that they split ozone in the upper atmosphere, destroy the ozone layer, hence allow solar UV to mess with ground-dwelling life. This doesn't really affect aquatic life (water isn't very transparent to UV). A secondary mechanism is direct irradiation -- really high energy gammas in the upper atmosphere produce a shower of muons and other short-lived particles, some of which can penetrate surface layers of the ocean before they decay, sterilizing the upper waters.

Firstly, we've only had an ozone layer to disrupt since the great oxygen catastrophe. (Would a sulphur-based biosphere be vulnerable at all? Or a methane one?[*]) And if that's the mechanism, it's going to be a poor way of sterilizing the land. Amphibian forms with a lifecycle that spends part of the time in the ocean (e.g. some eels) would be able to recolonize fast; ditto smaller insects. It'd only take a few million years for small land-dwellers to reappear, whereas the GRB extinction hypothesis doesn't seem to require GRBs to happen that often.

Secondly, the deep sterilization model ... again AIUI the frequency and intensity of GRBs might have made that possible, but only early on. And planets of stars with poor metalicity are going to have too little carbon or other metals[**] to evolve life as we know it in any case -- they're going to be mostly hydrogen/helium.

Finally, you're ruling out forms of life (evolving complex reactions) with a non-chemical basis, i.e. not based on condensed matter as we understand it. We know jack shit about exotic matter or quark matter or other high energy states, but it'd be foolish not to pause and consider the possibility that the real golden age for intelligent life in the universe ended about 3 minutes after the big bang, and we're chilly slow latecomers shouting "guys? ... guys?" in a graveyard universe!

[*] Although I think a methane-triplepoint biosphere is unlikely to have had time to evolve in the life of the universe to date; reaction kinetics say that cryogenic solvents are a slow environment for evolution to occur in.

[**] To an astronomer, there are three elements: hydrogen, helium, and metals (which is everything else). Almost all metals -- aside from some lithium -- are the result of nucleosynthesis in stars that subsequently went supernova. So only second generation planets are of interest. (Our solar system is believed to be third generation or thereabouts.)

67:
Assume we KNOW that there's an alien civilization of roughly our tech level with interesting stuff to chat about 50 light years away. Just HOW would we communicate with them?

I think this was addressed by Asimov 50 years ago. He used the example of his wife on the phone to another woman. They both told each other everything at the same time, which at least reduces the delay by a factor of 2. But I suppose we'd have to send them the story first!

As to the mechanics of "How", Arecibo message seems to have thought they could do it, (aimed wrongly, apparently!) and presumably military Radars could be used if SETI are right.

68:

1) If the death star blew up a planet tomorrow within our stellar neighborhood, would we see it, or find out about it?

Yes. Yes, we would.

(The minimum energy requirement for "blowing up a planet" is as much energy as its gravitational potential energy -- i.e. enough to remove all the energy binding it into a lump, allowing its pieces to drift apart. By memory, for an Earth-mass planet that works out at roughly equal to a day or so of energy output for our Sun. To shatter a planet like Alderaan[*] in a second, multiply by 86,400. So a flashlight five orders of magnitude brighter than the Sun suddenly switches on, then off again. I'd expect somebody to notice that!)

Why would any civilization build Dyson Spheres?

See "Accelerando". (BTW, the better formulation is a Matrioshka Brain -- not a simple shell, but a complex computing structure designed to maximize the thinking you can get done using whatever mass lies to hand in your solar system. So it can be of variable size. Oh, and the stuff already in orbit around your star is much easier to get at and manipulate than the bulk matter of the star itself -- and also more useful: most of your star is going to consist of hydrogen and some helium, which are not notably easy to build computers or habitats out of.)

Why would anyone build von Neumann probes?

To do exploration by proxy. (But again, see also "Accelerando" for why MB civilizations might not be very interested in exploring the neighbourhood.)

Your point (4) stands and I agree with you.


[*] Assumption: it's Earthlike. Going by the level of realism elsewhere in the "Star Wars" canon this is a highly dubious guess.

69:

It has to be said:

Going by the level of realism elsewhere in the "Star Wars" canon this is a highly dubious guess.

I find your lack of faith disturbing.

70:

an alien civilization could send probes traveling no faster than 10% the speed of light to every single solar system in the galaxy in only 10 million years.

This tells us nothing unless we know it's possible to boost a probe up to 10% of the speed of light and slow it down at the other end.

That's a hard problem!

I'd shoot for a maximum cruise speed of 1% of c, and even that's a bit high -- a more realistic one would be 0.001% of c. You can do that with solar powered xenon ion drive thrusters -- xenon isn't very volatile and solar power could in principle be available at the destination, allowing for deceleration. However, it adds 3 orders of magnitude to the colonization time, suggesting the VNs could take on the order of billions of years to saturate our galaxy. If we then postulate that it takes a third generation planet to spawn a biosphere with complex life, we're now getting into the ballpark where VN-mediated exploration and even colonizaiton could be happening but we haven't seen signs of it yet.

71:

A solar sail about the size of Colorado (and being only one carbon atom thick) can use the pressure of sunlight alone to accelerate a payload to between 0.01c to 0.1c. Deceleration can be achieved by the pressure of sunlight from the destination star.

Bullshit -- not without a lot of fancy extras.

Your 1-carbon-thick sail (fullerene, right?) is going to be hitting the interstellar medium at upwards of 1% of lightspeed. At that velocity, a stationary helium nucleus packs the punch of an alpha particle; and each cubic meter of vacuum contains a couple of hundred hydrogen molecules. Run the math: at 1% of lightspeed you're travelling at 3000 km/s, or 3M metres/sec, so each square metre of light sail is exposed to the equivalent of roughly 30 MBq of radiation per second.

I suspect said light sail will be in tatters before it even gets out of the solar system, unless it's a lot more massive, and/or contains self-repair mechanisms, and/or is travelling a lot more slowly, and/or some other safety mechanism is in place (it can be reefed like a sail for cruise flight -- or like an umbrella -- but then needs to be unfurled again at the other end).

As for "artificial wombs", I've taken a pick-axe handle to that idiotic colonization proposal before. Let's just say there's more to human beings than raw genetic material, and colonizing another planet using that technique is an AI-complete problem.

72:

The Rare Earth Hypothesis is not the same as rare planets.

Correct, and this bears repeating. (It's one of the background assumptions behind the SFnal world-building in "Neptune's Brood": true Earthlike worlds are quite rare.)

73: an alien civilization could send probes traveling no faster than 10% the speed of light to every single solar system in the galaxy in only 10 million years.
I'd shoot for a maximum cruise speed of 1% of c, and even that's a bit high -- a more realistic one would be 0.001% of c.

Even at 0.001% of light, that's still only 10 billion years. Oh for a Conjoiner drive!

74:

Our galaxy is a bit less than 10GYa old. Only 13.7GYa have passed since the big bang. So there's that.

75:
not a simple shell

Dyson's original Sphere wasn't a simple shell, either, remember.

76:
Our galaxy is a bit less than 10GYa old. Only 13.7GYa have passed since the big bang. So there's that.

Good point! Does this mean we can legitimately infer a minimum velocity for an expedition to another star or a galactic colorization effort?

77:

Oh come now Charlie! THE STAR SHIP CAPTAIN would declaim SHIELDS UP! Before ever the sails got tattered...don’t know why HE would need to declaim this rather than that the said Shields UP thingy engaging automatically...a bit like self driving cars recognising obstacles... but it happens all the time in Star/War /Trek type TV/Films and it is Ever So Dramatic!

Anyway Magical Magnetic Shields - otherwise known as 'WARDS ' in Urban Fantasy and deployed by Magic Users of The Captain Grade - would Do the Job.

Or in Song...When You Wish upon a Star DoDnt matter who you are...when you wish upon a Star Your wish ...and so on and so forth.

https://www.youtube.com/watch?v=HKh6XxYbbIc


“No request is too extreme”

There ..fixed it for you!

78:

Add in a fudge factor for the increasing expansion rate of the universe ... or were you thinking of exploring only the home galaxy (Milky Way)?

What if the likeliest sentient-producing planets are more or less similarly distributed around/within a galaxy because of the relative abundance of a sufficient/requisite variety of metals (i.e., everything in the table of elements above Helium)? As per below ... "Our solar system is at the edge of a spiral arm called the Orion Arm, and is about two-thirds of the way from the center of our galaxy to the edge of the starlight." This would add some travel/navigation time as well. Or, we could target likely up-and-comer planets that have yet to reach the same level of development - either for biologic colonization or just to study.

http://hubblesite.org/reference_desk/faq/answer.php.id=37&cat=galaxies

79:

So aliens roughly 60 light years away are not watching origial broadcasts of "I Love Lucy"?

80:

I'm aware of that; trouble is, most people who discuss Dyson spheres evidently don't know this key point.

81:

Yes. Unfortunately that velocity is on the order of the velocity the New Horizons probe has already reached, and is available with not-quite-off-the-shelf-but-not-hypothetical-either technology today.

82:

>Secondly, the deep sterilization model ... again AIUI the frequency and intensity of GRBs might have made that possible, but only early on. And planets of stars with poor metalicity are going to have too little carbon or other metals[**] to evolve life as we know it in any case -- they're going to be mostly hydrogen/helium.

Hence the lack of Ancient Old Ones. Maybe the Star Trek univese got it right with the vast majority of intelligent species evolving at roughly the same time (the occasional super evolved Organian species made of pure thought energy notwithstanding).

>Finally, you're ruling out forms of life (evolving complex reactions) with a non-chemical basis, i.e. not based on condensed matter as we understand it.

I'm also ruling out ghosts, spirits, pixies and fairies. Until our understanding of the laws of physics advances far enough tounderstand how such exotic matter could become intelligent life it would be intellectually dishonest to let our imangination run beyondthe known limits.

Based on what we know now, we are alone. Any other possiblity involves special pleading.

83:

Try a web search for " oort cloud aliens TV broadcasts " but, even without such researches, it seems perfectly reasonable to me that those Aliens have copies of ALL of those missing episodes of TV series that were erased from magnetic tape by the B.B.C.in an effort to save money

84:

Oddly enough,the massive magnetic field required for a Bussard ramjet would actually act as a massive brake on a space craft traveling at a large fractionof c as hydrogen and helium build up in front of it (one of the reasons the ramjet wouldn't work).

Such a massive magentic field would act in the same way as aerobraking to slow down a spacecraft.

85:

I believe some more recent analyses of our radio-spectrum output suggests that any TV or audio radio broadcasts are orders of magnitude too feeble to pick up at interstellar distance. Worse, shorter wavelength emissions tend to smear with distance/refraction/absorption via the interstellar medium. So while aliens 50ly away might have noticed a sudden spike in radio emissions from our direction, they'd have to get cracking to build a big-ass highly sensitive receiver to make any sense of it ... and it's now tapering off into low volume mush, thanks to efficient modern codecs.

But then there's Duga-3 ballistic warning radar (the "Woodpecker"), which punched out a shortwave signal using 10MW of emitter power and used a a 31-bit pseudo-random binary sequence, with a bit-width of 100 μs resulting in a 3.1 ms pulse to tag its packets (and make it hard to jam). So: regular high power signal with non-repeating information content. Possibly there are some bug-eyed green-skinned mathematicians busting their guts to this very day trying to extract data from it.

86:

>I suspect said light sail will be in tatters before it even gets out of the solar system, unless it's a lot more massive, and/or contains self-repair mechanisms, and/or is travelling a lot more slowly, and/or some other safety mechanism is in place (it can be reefed like a sail for cruise flight -- or like an umbrella -- but then needs to be unfurled again at the other end).

That's really not all that fancy of an extra mechansim. Neither would be a paylod equipped with swarms of repair nanobots that search out and repair tears and tatters. Human crews repaired the sails of their sailing ships as a matter of course. Why should a solar sail be any different?

As for "artificial wombs", I've taken a pick-axe handle to that idiotic colonization proposal before. Let's just say there's more to human beings than raw genetic material, and colonizing another planet using that technique is an AI-complete problem.

So what exactly is wrong with the "seedhip" concept? I'm genuinely curious as to your opinion on the idea.

87:

So what exactly is wrong with the "seedhip" concept? I'm genuinely curious as to your opinion on the idea.

If all you want to do is deliver bacteria, it'll work fine. However, if you want to socialize mammals, you're asking for a lot more. And if you want to raise human beings, you need a human being: we don't come pre-configured out of the box.

88:

>Possibly there are some bug-eyed green-skinned mathematicians busting their guts to this very day trying to extract data from it.

Or conversely, human mathematicians at Ohio State University trying to detemine if the so-called "Wow Signal" was artificial or not.

89:

Sufficiently advanced Mommy and Daddy androids (that get turned on upon arrival) would not be good enough to raise the first generation of kids?

90:

Androids that can raise newborns to adults would basically be people.

91:

Sufficiently advanced Mommy and Daddy androids (that get turned on upon arrival) would not be good enough to raise the first generation of kids?

Like I said, it's an AI-complete problem; if we can build human-equivalent AI, then it's no big deal. But if we can't ... how'd you feel if for your entire childhood you'd had no interactions with other human beings? Just television channels or gameable expert systems? We're mammals, we come with theory-of-mind baked in. If something doesn't have a mind, eventually we figure it out, and if it has a mind (but a simple one) we work out how to think around it. Kids raised by a non-sentient agency will be odd, to say the least. More likely they'd be extremely badly damaged.

92:
, human mathematicians at Ohio State University trying to detemine if the so-called "Wow Signal" was artificial or not.


Still? Presumably they'd be best focusing on HEVC video encoding theory! Though I was told perfectly encoded information would sound/look like static unless you've got the "codec". Sounds reasonable to me...

According to the New Scientist, WOW originated near the Teapot constellation! Which is a nice coincidence given OGH's cleaning series.

93:
it seems perfectly reasonable to me that those Aliens have copies of ALL of those missing episodes of TV series that were erased from magnetic tape by the B.B.C.in an effort to save money

The solution to the Fermi Paradox is that everyone has been receiving our broadcasts since the start of TV and Radio 4, hence they're terrified of a takeover by the federation, that Kirk will seduce all their "women" (he was never fussy) and Linda Snell... is our doomsday device.

94:
, human mathematicians at Ohio State University trying to detemine if the so-called "Wow Signal" was artificial or not.

FWIW, I think this was addressed in Niven & Barnes's "The Legacy of Heorot". Or was it "Songs of Distant Earth"?

95:

Wrong!!

Intended to reply to 91 ( Daniel Duffy ).

96:

I, for myself, blame Bob Shaw's Orbitsville for that misconception. I think it was one of the first encounters with a concept like that, and the image stuck.

The Traveller role-playing game also has Dyson spheres, and that's probably the second place I did see them.

I did read Dyson after that, though.

97:

"Until our understanding of the laws of physics advances far enough tounderstand how such exotic matter could become intelligent life it would be intellectually dishonest to let our imangination run beyondthe known limits."

"Based on what we know now, we are alone. Any other possiblity involves special pleading."

I find this reasoning fascinating, because I don't understand it.

To my way of thinking, if somebody said "I know there are intelligent aliens out there" and gave us their reasoning, I'd argue that they don't know enough to say that. But when you say that you know we are alone in the galaxy and you give your reasoning, I don't think you know enough to draw that conclusion either.

If somebody wanted to make a bet with me whether there are intelligent aliens, give what I know so far I'd figure it's reasonable to bet there are not. But then if we discussed what odds to give to make it fair, I'd say 52:48 would be about right. I don't think we know enough to give better odds than that, that there aren't intelligent aliens in our galaxy.

And then say somebody wanted to make a side bet, as follows: Given what we know now, if we really thought it out carefully, is 52:48 the better odds or would 20:80 be closer to the fair bet?

I couldn't be sure which of those is more fair. I guess I'd give 51:49 odds that my 52:48 odds are better than a 4/5 chance I'm wrong about it. I just don't know very much.

Saying that it would be intellectually dishonest to consider that the things we know nothing about might turn out in ways that we would be irrationally surprised about -- I just don't get that reasoning. But I see people do it a whole lot.

98:

Another way to say the same thing is that humans require two modes of inheritance: cellular and cultural. The cellular inheritance (genome, epigenome, etc.) is what we share with all life. But culture is required for proper human development too. We can't survive without loving interaction with adults and others, and not just because we're helpless as newborns.

Note that I'm not saying that newborns are blank slates upon which anything can be written. Still, we are immensely flexible, and we can be hunters, gatherers, fishermen, writers, housewives, rulers, gymnasts, astronauts, engineers, miners, etc. depending on the culture we're brought up in and our experiences. No other animal is remotely that flexible, even ones (like apes) that also have cultures. Culture affects every aspect of our biology, from our brains to our blood chemistry, fat, bone structure, gut bacteria, and so forth. The culture we grow up in makes us who we are, both physically and mentally.

99:

"Kids raised by a non-sentient agency will be odd, to say the least. More likely they'd be extremely badly damaged."

A civilization that has developed the technology to send big complicated probes to other stars, might understand human development well enough to create functional first-generation humans who grow up with no human adults around them.

I don't know that they could do that. On the other hand, what's the chance that they could handle the power required to do the physical part, and survive, and still *not* understand a whole lot about how to build functional human beings?

I don't see any sort of guarantee that we could solve that problem. It might not be possible. But I also don't see any guarantee that we couldn't solve it.

I heard that in Newton's time people speculated that human beings could reach the moon if they had a big enough cannon to shoot them there. But the kind of charge the cannon would require would squash the people to jelly inside their cannonball.

They didn't really know what kind of technology would be available later. And neither do we.

100:

My personal take is that probably any intelligence we send to the stars will be machine based (who need genes if you can efficiently transmit culture on some other substrate?). That said, keeping a terrarium full of humans alive for more than a generation is a major feat. Therefore, it might become a status symbol to have a terrarium full of humans in your space colony. Others would think twice of messing with someone who could pull off the trick of keeping a colony of humans alive and breeding. It would take a lot of resources, complex logistics, and a lot of skill, all things that could be repurposed into say, military activities.

And, as always, such terraria are probably unstable in the long-run. More humane machine intelligences might therefore release humans on the nearest more-or-less habitable planet, possibly with some resources to see if they can make it in the wild.

That might be our best chance for colonizing other planets, as discarded status symbol pets. Cue the sad trombone music.

101:

Heteromeles, I like that idea!

Of course, we don't know what technology we'll have by that time. It might turn out that in some environments organic machines are more efficient than metal ones, particularly environments that have lots of CHON. It might make sense to spend a few thousand years turning a reducing environment to an oxidizing one, and take it from there. And it might eventually become something that humans could survive in.

Of course, organic life is pretty unstable, but -- horses for courses. And if the home world is doing it as a sort of afterthought, they might not mind other worlds being stocked by humans who might eventually get locally powerful and wipe themselves out -- as long as the humans on other worlds can't make significant attacks on the home world.

On the other hand if they had real sciences of psychology and sociology, they might design cultures that would actually do what they thought ought to be done. Whatever it was they thought human societies ought to do....

102:

A civilization that has developed the technology to send big complicated probes to other stars, might understand human development well enough to create functional first-generation humans who grow up with no human adults around them.

Maybe, but there would be huge problems. Starting with what your Ethics Oversight Committee will say about the way you design your preliminary experiments in "creating functional first-gneration humans who grow up with no human adults around them".

Hint: you're not going to go for gold on your first interstellar mission without prior research, right?

Second hint: the human rights of your test subjects ... (there's a reason new medicines get product licenses that explicitly exclude pregnant women and babies, and those classes only get included once a bunch of additional post-sale data from the field is available for crunching: it's called "informed consent" and babies can't give it).

Frankly, I think we're closer to being able to engineer a probe able to conduct a successful interstellar flyby (circa 1-10% of lightspeed, range 5-20 light years) than we are to being able to automate child-rearing. And the latter has vastly more profound implications for us -- seismic, even. (For starters, think what a polity unconstrained by ethics committees might do with such a technology ...)

103:

That might be our best chance for colonizing other planets, as discarded status symbol pets. Cue the sad trombone music.

And that's the should-have-been-bleeding-obvious plot armature for a third novel in the Freyaverse, of course: a colony of humans abandoned by the Church of the Fragile (because it succeeded) coming to terms with their place in a universe colonized by, er, robots-but-we-don't-call-them-that. I'll just have to write it in my copious spare time ...

104:

Automated child rearing and the ethical objections could be overcome if the first colonists were genetic duplicates of volunteers on Earth.
Memory recording and implantation could be used in place of socialising the children who would be empty vessels waiting for their adult memories to implanted after they had been regrown by machines.
This first generation would then be available to bring up the next generations.

105:
Automated child rearing and the ethical objections could be overcome if the first colonists were genetic duplicates of volunteers on Earth. Memory recording and implantation could be used in place of socialising the children who would be empty vessels waiting for their adult memories to implanted after they had been regrown by machines. This first generation would then be available to bring up the next generations.

We might be a few years away from that kind of tech! Reminds me of Richard Morgan's Takeshi Kovacs novels where the implications are explored to some degree. Unhappily he's abandoned the series, from what I gather are essentially ethical reasons (but might be wrong). I really want someone to write "Things I Should Have Learnt by Now, Volume II" and apparently Quellcrist Falconer appears not to exist.

If we had mind / memory uploading & downloading, it would change everything assuming it wasn't only available to the super rich, even then do you fancy a world where the rich are immortal?

Might make for longer term projects, amongst other things.

Mind you, if I had a trillion quid, it'd change everything too, not least trying to figure out how to parse h264 SEI messages for timecode data in an h.264 transport stream. "If", such a small word...

Seriously though, presumably in order to upload ones "mind state" one would first need to record it. Is anyone looking into this, academically? I imagine until we have a better idea of how we think in terms of the low-level mechanisms, this is a bit of a non-starter.

106:

Automated child rearing and the ethical objections could be overcome if the first colonists were genetic duplicates of volunteers on Earth.

Ahem: we have a technical term for "genetic duplicates" today: we call them "identical twins". Firstly, on the pragmatic side, epigenetic modulation means that "identical" twins aren't (as you'd be aware if you'd hung out with any). Secondly, on the legal side, identical twins are seen as distinct individuals -- I can't be charged with attempted murder if I try to kill myself, but you watch what happens when I take a half-brick to my [imaginary, identical] sibling's skull!

Memory recording and implantation could be used in place of socialising the children who would be empty vessels waiting for their adult memories to implanted after they had been regrown by machines.

Yeah, right. Firstly, show me a machine that does what a uterus does. (Hint: it's a really non-trivial piece of medical tech, many orders of magnitude more complex than an artificial heart or a renal dialysis machine: just scan the list for "coulds" and "mights" in this panglossian wikipedia entry -- and I don't think it mentions the role of immune system modulation or human endogenous retroviruses in transferring epigenetic information across the placental barrier from the mother.) Secondly, memory recording ... this is a "magic wand" technology: we are nowhere near being able to do this, and the closer you examine at human neurobiology the harder it looks.

Basically, the two items you listed are stacking a Mars colony on top of an Apollo-grade moon shot, in terms of the biotechnology involved. Not saying it's impossible, but they're nothing you can shrug off as trivial details in comparison to building an interstellar probe -- they may actually be much, much harder.

This first generation would then be available to bring up the next generations.

Assuming they want to. See also: "We who are about to ..." by Joanna Russ. (Assuming that page hasn't been vandalized by the MRAs yet.)

107:

"I think we're closer to being able to engineer a probe able to conduct a successful interstellar flyby (circa 1-10% of lightspeed, range 5-20 light years) than we are to being able to automate child-rearing."

I agree, and yet I don't know how to predict scientific and technological breakthroughs more than 25 years ahead. I can figure that things the scientists can't imagine now, probably won't come in within the next 5 years because the scientists won't imagine it. And once we get fundamentally new science it will take at least 20 years to get functional new technology from it. But past that? I would not have predicted Maxwell's equations if I had been there in 1840, or relativity in 1880, or the transistor in 1920.

"And the latter has vastly more profound implications for us -- seismic, even."

Definitely!

If we understood how human personalities are formed, would we want them to be formed entirely at random? Resulting in sexual fetishes for latex suits and sports cars etc? Rapists and weird religions? People who're so scared of humanity they become authoritarians? Schizophrenics and Randites?

If we knew how formative experiences worked, surely we would want our children to have good ones, that let them be the sort of people we wanted them to be.

I expect there would be cults that insisted their children be raised at random. It would not be surprising if the rest of society insisted that those children have tattoos on their foreheads so regular people would have some warning.

If we decided to send humanity to the stars, I'm sure we would have lots of experience with creating personalities first. Unless that technology was unavailable, in which case we would probably re-invent your objections to humans raised with no human supervision, and likely decide not to do it after all.

108:

If we had artificial wombs, I wonder how the anti-abortion crowd would react? How would law change?

Which is to say the availability of the tech required for an interstellar expedition would probably have profound consequences ( good and bad ) when made available back home.

109:

Frankly, I think we're closer to being able to engineer a probe able to conduct a successful interstellar flyby (circa 1-10% of lightspeed, range 5-20 light years) than we are to being able to automate child-rearing

I get your point, but I'll remind you that you're talking about a probe with a flight time of 50 to 2000 years. Even so, it would be going at speeds, in Earth terms, of between Mach 9,000 and ten times that. Also, we have no realistic idea of how to get data back from such a probe. Also, if at any time in its flight it hits a stray pebble or too big a dust mote, game over. So I'd say the child-rearing thing is more feasible.

110:

If we had artificial wombs, I wonder how the anti-abortion crowd would react?

<political-digression>
The anti-abortion movement isn't about "protecting the children" or any guff like that, it's about keeping teh wimmin barefoot and pregnant in the kitchen, where the anti-abortion people believe they belong. Female reproductive autonomy is an existential threat to traditional patriarchal values, so must be resisted: as witness that whenever they get close to winning the fight to restrict access to abortion, they up the ante by trying to ban contraception as well. There are people out there who believe "The Handmaid's Tale" is a road-map, not a dystopia, and not all of them live in Da'esh-controlled territory in the Levant, or in Afghanistan.
</political-digression>

(Note: dissenting opinions on this topic may be red carded, depending on presence of knee-jerkiness. I tend to lose my sense of humour in the presence of people who advocate removing basic human rights from some category of people on the basis of their genetic make-up, e.g. possession of a pair of "X" chromosomes.)

111:

Also, we have no realistic idea of how to get data back from such a probe.

Disagree about the getting-data-back bit; although it'd be difficult (what kind of heat sink do you need for the 10-100MW laser transmitter's power supply? What kind of bit rate can it maintain?) it's not obviously more difficult than accelerating a big hunk o' tech up to 1% of light speed or faster (which is to say extremely difficult but not forbidden by the laws of physics).

Also, if at any time in its flight it hits a stray pebble or too big a dust mote, game over.

Yes, which is why it's going to need some very sophisticated anti-impact shielding. (My guess: a mylar light-sail, boosted a few thousand kilometers ahead of the ship by that on-board communications laser. It might only be 0.001 millimetres thick, but when that hypothetical piece of gravel hits it there are going to be fireworks, hopefully vapourizing said piece of gravel before it runs into the ship itself. Put your solid-phase fuel in front of the valuable payload to absorb the radiation impulse from the explosions, and replace the mylar shield regularly as it gets ablated; use lidar to look for and maneuver around really big obstacles, because hitting a KBO at 1% of light speed will totally ruin everybody's day (and probably be visible at a range of light years if your starship is of any size at all -- kinetic energy at that velocity is the equivalent of a 200 kiloton H-bomb for every kilogram of mass in the ship).

112:
The anti-abortion movement isn't about "protecting the children" or any guff like that [...]

Of course not. Well, that said, I suppose it might be at the individual level of the grass roots movement. But yes it's about political control, on a macro level, and driven by ideology.

But to paraphrase REH, when a man speaks of his honour, make him pay cash. Anti-abortion movements, are singularly remiss in materially supporting those who seek an abortion. On the political side Sara Diamond is worth reading on this in "study and expose the agenda and tactics of the American political right wing." and "Spiritual Warfare: The Politics of the Christian Right Spiritual Warfare: The Politics of the Christian Right ". Closer to home Robert A. Gilbert (who might pass for Angleton on some days, in lots of ways" says interesting things in "Casting the First Stone: Hypocrisy of Religious Fundamentalism and Its Threat to Society".

Diamond contends the FBI refused to catagorise the spate of abortion clinic bombings in USA during the 80s & 90s terrorism, for political reasons.

I wonder what R. J. Rushdoony thinks of ISIS?

113:

Charlie, I agree with you, but an artificial womb would undercut the antiabortionists overt objections to abortion. This would, possibly, force them to reveal their real, anti-woman,position

114:
because hitting a KBO at 1% of light speed will totally ruin everybody's day

It would be par for the course that our robotic interstellar probe, discovers aliens, and subjects their planet to an accidental relativistic bombardment. Which as you say would spoil their who day, or aeon.

How do you say "Oops, Sorry" in Alien?

115:

That mylar lightsail may not be the solution.
A few days ago I was listening to the spaceshow(dot com).
In episode 2415 the guest, Les Johnson, is involved in lightsails. There were worries about micrometeorites and the sail. The thought was that micrometeorites would destroy the sail on impact. Didn't happen. Punches straight through with just a tiny hole that has no impact on performance whatsoever. What didn't happen was transfer of momentum from the micrometeorite to the sail. The sail is too thin and the dust too fast.

A thought I've been playing with is aerogel or aerographene. Aerographene weighs 160 g/m3. Build your self a small mountain in your flight direction to protect against dust.

116:
The thought was that micrometeorites would destroy the sail on impact. Didn't happen. Punches straight through with just a tiny hole that has no impact on performance whatsoever. What didn't happen was transfer of momentum from the micrometeorite to the sail. The sail is too thin and the dust too fast.

Being old, and of a conservative disposition as regards "live systems", I'm curious to know if this was a theoretical study or tried for real.

117:

Since no-one else appears to have mentioned it, I thought it might be worth sharing a story by Mark Tilden a robocist who created a mine-clearing robot that looked something like a stick insect. It would find a mine and detonate it, losing a leg in the process. Eventually the robot was dragging itself forward with its last leg blithely searching for another mine to detonate when the army colonel in charge of the test halted it because he felt it was inhumane -- hge couldn't stand to watch it piteously scrabbling forward with its last let headed for certain doom.

And no-conversation about the emotional appeal of robots would be complete without a video of Keepon dancing.

118:
when the army colonel in charge of the test halted it because he felt it was inhumane -- hge couldn't stand to watch it piteously scrabbling forward with its last let headed for certain doom.

I wonder how many drone drivers get PTSD.Presumably that's classified.

119:

The guest of the show presented it as a conclusion.
Go to thespaceshow.com, download episode 2415 and listen.

The guest:
Les Johnson
Les Johnson is the Deputy Manager for NASA’s Advanced Concepts Office at the Marshall Space Flight Center in Huntsville, Alabama. He is a co-investigator on a Japanese space tether experiment that will fly in the summer of 2009. During his career at NASA, he served as the Manager for the Space Science Programs and Projects Office, the In-Space Propulsion Technology Program, and the Interstellar Propulsion Research Project. He was the Chief Scientist for the ProSEDS space experiment, twice received NASA’s Exceptional Achievement Medal, and has three patents etc etc

121:

Well, isn't there data in the form of medical studies?

This following linked from a vague memory of reading about this sort of thing in The Torygraph ...

" The stress of constant operations and long shifts, albeit with rest breaks, has led to fears of burnout among Reaper pilots. The almost limitless demand for 'overwatch’ creates a huge workload: every stream and every suspicious-looking building on a convoy route is checked for IEDs or a potential ambush by Reapers before troops go out on patrol.

The usual pattern of war fighting is to spend four months in a war-zone before returning home. But the Reaper pilots at their base in Nevada are commuter warriors: they work five days a week and drive home to their families at the end of their shifts. A tour of duty for them can last years. This changing tempo of war is taking a toll on pilots, even though they are not themselves in harm’s way. According to a survey by the Air Force School of Aerospace Medicine, nearly half the operators of UAVs have high levels of 'operational stress’ caused by long hours and extended tours of duty. "

http://www.telegraph.co.uk/news/uknews/defence/9552547/The-air-force-men-who-fly-drones-in-Afghanistan-by-remote-control.html


Also, given this sort of report from other civilian sources ...

" War Child warns of more child casualties from use of drones "

http://www.theguardian.com/global-development/2013/oct/23/advanced-weapons-increase-child-casualties

It would be a very strange thing indeed if drone pilots didnt have a significant rate of Post Traumatic Stress Disorder.

In these days, when any cloud might hold a Predator Drone, any sensible Death Cult Leader would be wise to surrounded himself with Disney Cute Little Children all trained to look as if they were Singing .. " Wouldn't it be Nice if Everyone was Nice .."

122:

I wrote a book set in such a universe years ago, but unfortunately I didn't write it well enough to sell it. Maybe someday I'll go back there and try again.

123:
. " Wouldn't it be Nice if Everyone was Nice .."

Yes it would, But as Pratchett observed, there is the dreadful logic of necessity always lurking in the background.

124:

Never mind solar sails & memory uploading &c. What would be the result of a drug that ramped up empathy? Kind of the opposite of Equilibrium (film).

By "empathy" I mean the ability to imagine/envisage/perceivewhat it's like for the other guy/girl. Not just in terms of feelings, but in terms of the totality of their life and material circumstance.

If I really cared I'd do something significant about it. But I don't, so I don't. Or at least nothing significant. With a major empathy boost I might be motivated to. Mind you, when I pay off my mortgage next month, my attitude might well improve, or not...

125:
This following linked from a vague memory of reading about this sort of thing in The Torygraph ...

thanks for that.One wonders about the PSTD level at the Telegraph.

126:

That mylar lightsail may not be the solution.
A few days ago I was listening to the spaceshow(dot com).
In episode 2415 the guest, Les Johnson, is involved in lightsails. There were worries about micrometeorites and the sail. The thought was that micrometeorites would destroy the sail on impact. Didn't happen. Punches straight through with just a tiny hole that has no impact on performance whatsoever. What didn't happen was transfer of momentum from the micrometeorite to the sail. The sail is too thin and the dust too fast.

This result doesn't trivially extrapolate up to 0.01 C though. A micrometeorite may be traveling at 50 km/s relative to an interplanetary solar sail. At 3000 km/s relative closing speed with an interstellar probe-sail there's 3600 times as much kinetic energy.

127:

And how big do you think your laser would have to be?! It's not gonna fit on a shark, that's for sure. If you can get to a billionth of the sun's luminosity we'll discuss it. Less than that and you'll be swamped. Even if you push it out a few milliparsecs, I still think you're looking at one heck of a power bill; y'know 17 zeros. And extinction is another factor of 5 for every kpc. However you can use an array - a synthetic aperture might miss it, but a normal one would integrate. And if you knew precisely where it is was in advance (e.g. a colony), I might allow you a few hundred TW, plus extinction.

Me, I'd shutter the sun. Build giant paddles that can either be perpendicular to the sun (allowing light to pass) or turn to face the sun (blocking light). Perhaps it could be done with solar sails that are released and gathered up. It doesn't have to be solid, either, just introduce an absorption line. Either way, a few billion of them (perhaps far less for the absorption line), each a kilometre square, and you might be able to do something measurable to modulate the sun's output. And there's something steampunkally pleasing about interstellar communication vis Aldis lamps... Bit rate, 12μHz

But how do you tell other civilizations we're here? What sequences of magic numbers would look nothing like an astrophysical process and yet would be recognisable to an intelligent civilisation as the start of a frame? A000040 maybe? :P :P

128:

You'd lock yourself in a bunker, afraid to go out or say anything for fear of hurting anyone - and therefore by extension - hurting yourself. As the drug started to wear off, you'd do something insensitive and then, once back on full does, you'd become depressed at all the pain you'd caused. And even without that, you'd be depressed about all the people you couldn't help.

129:

Good point. Full response tomorrow, assuming the Kitten doesn't Drink all my blood tonight.

130:

You wouldn't necessarily be more scared of hurting other people than you are of getting hurt yourself.

Imagine that "empathy" was a sense of how you would feel if you were in the circumstances the other person is, plus a sense of how the cues they provide you don't fit that, so that you get some indication how they respond to those circumstances differently from the way you would, and you imagine how they would think about things to have that response.

Not magic or telepathy but the normal behavior that we all normally do.

Then a drug might make that more immediate. It would affect your attention so it would be harder to ignore that.

People could still use their usual rationalizations. "He's making a mistake. I used to make that mistake and I got hurt by it. He just has to feel the pain so he'll learn better and stop hurting himself that way." "Serves him right, he shouldn't have tried to cross me." "Sad the messes people get themselves into, but it isn't my responsibility. I can't take care of very sniveling coward in the world."

They could still do it, but they'd have a harder time trying not to notice what the other guy was feeling. It wouldn't have to keep them from functioning in the world.

131:

Quantum mechanics sets a minimum beam spread on a laser. For lasers with reasonable wavelengths and plausibly-sized apertures, the signal attenuation over interstellar distances is extreme. Of course, having a star in the background won't help; the difference in angle between the probe and the destination star is going to be extremely small from an the perspective of an observer on Earth.

These problems could hypothetically be addressed with a big enough laser, a big enough battery, and a big enough heat sink. "Big enough" for communications purposes almost certainly means "orders of magnitude too big" for launch/acceleration purposes.

Also, it does little good to vaporize a micrometeorite in the probe's path. The difference between a solid and a puff of gas is insignificant when it's impacting at 3 million meters a second.

132:

"Also, it does little good to vaporize a micrometeorite in the probe's path. The difference between a solid and a puff of gas is insignificant when it's impacting at 3 million meters a second."

Depending on the technology available, you could have a small linear accelerator that pushes protons ahead of you at close to lightspeed. When they hit stuff ahead of you, it could give you a signal which might give you a little warning. Also it would tend to charge whatever mass it hits.

Then if you send a bigger tightly focused pulse of protons to go close to the positively charged mass, it will tend to accelerate it out of your path. Whether you can accerate it enough out of your path that it misses you, is a small matter of engineering....

Of course it's both easier and safer to go slower, provided your machinery and cargo can both keep well.

133:

I believe that NASA used aerogels to capture particles in space( see http://en.wikipedia.org/wiki/Stardust_(spacecraft) ). So my guess is that they should work as sails if the particles are completely trapped. Not sure how would increase of mass ruin the gain of momentum.

134:

I keep thinking that some form of magnetic shielding may be useful, not to stop any incoming junk, but to redirect it just a little bit. For example, if a starship was using something like a magsail (some setup of charged, superconducting cables, it might make sense to distribute the starship as pods around the circumference of the magsail (assuming it's circular), then try to deflect anything incoming into the space in the empty center of the sail where it won't cause any damage. Of course, this gets messy when both positively and negatively charged particles are considered, but conceptually it makes a bit more sense than basically letting the ship sit in something that's close to the beam path for the LHC for 1,000 years, or however long it takes to travel between stars, and assuming that whatever shield the ship is carrying can stand that kind of abuse for 1,000 years. Of course, it's more likely that starships will turn out to be impossible engineering challenges, but I guess that's too boringly practical to consider.

Incidentally, has anyone considered what civilization will look like if it is possible to make a starship shield? Supervillains having impregnable lairs will stop being a stupid trope and start being a real problem, to name only one tiny issue. Or imagine the joys of nuclear war if every side thinks their fortifications can withstand any weapon the other side can throw at them.

You can't imagine starship technology in a vacuum, even though so many authors try to. Any society that produces starships is going to look very, very different from our own, simply because all the different fundamental innovations required to make starship technology work are going to show up in everything from military technology to social norms to city design.

It's silly to isolate such a radical technology off to one side, really. It's akin to talking about an America where everyone lives in bark wigwams and we conduct our diplomacy with sachems transported by nuclear-powered aircraft carriers. Yes, quite a few SFF books do this kind of futurism routinely.

135:

For soft science fiction, it's a genre convention to pretend the starship is much less impossible than it is. The author wants to tell a story about aliens or some such, so a starship of some sort is a necessity.

It's like how we don't talk about metabolism in a zombie story. If you can suspend disbelief, you go with it. If you can't, you put the book down.

P.S. I particularly loved how Interstellar was hailed as "hard" science fiction when it's premised on a theoretically-plausible-but-never-observed wormhole phenomenon that just happens to, against trillions to one odds, pop in to existence with one end in range of a human space program and another end in range of somewhere worth exploring. Shoving children into coat closets is only marginally less plausible as a means for interplanetary transport.

136:

This result doesn't trivially extrapolate up to 0.01 C though.

Any experimental data to backup your opinion?

137:

Ugh, the Strange Attractor strikes again. Stahp, what are you doing? We discussed it all before in like seven threads. Stahp!

...

Ah, what the hell, once more unto the breach, dear friends, once more! Seriously, we don't need sub-luminal spaceships to colonize the galaxy, we just need life extension technology. Then people can take their time coasting through space for millennia.

And then people will actually have the motivation to go, since they can arrive alive, build a civilization, then come back if they want. No one but a tiny minority will pay for a ship full of embryos or similar nonsense. But immortals will pay for a very long vacation.

And since life extension technology is actually something people will want here on Earth (as opposed to horrible torch-ships), this is what we will get.

/inb4 Charlie hits me with the argument that no mortal flesh can survive the journey through the Poison-Laced Void...

138:
Depending on the technology available, you could have a small linear accelerator that pushes protons ahead of you at close to lightspeed

So… continually firing a rocket in the opposite direction you want to travel in?

139:
Brave space robots literally make me misty.

Immediately thought of this cartoon

140:

/inb4 Charlie hits me with the argument that no mortal flesh can survive the journey through the Poison-Laced Void...

Nope. Remember those earlier threads that resulted in valuable grist-chewing that fed into "Neptune's Brood"? Yes, with life extension (and pleasantly habitable -- not marginally habitable -- space colonies) we could do it. But then I anticipated the biological issues. So we end up with the people of the Freyaverse: call it Humanity 2.0, overhauled to make long-duration space flight survivable.

This is an extremely difficult bunch of technologies to master and it'll take us centuries at our present rate, but it gets around the little problems with high energy physics that proposals for relativistic travel require us to ignore, and I suspect it's going to turn out to be marginally-to-considerably easier than mind uploading/simulation on general purpose computing hardware.

(Also: looking at the modern biological sciences through eyes educated in 1920s biology/medicine is well worth it, just for the insanely dizzying perspective it gives you. Most folks don't realize just how far we've come.)

141:

I've been reading through the latest (excellent and insightful) comments about the pros and cons of each type of interstellar exploration/colonization method and technology - the question being which one is best.

Answer: All of the above.

Acceleration would be accomplished with huge solar sail only one carbon atom thick (additional energy from powerful orbiting laser optional). Once cruise speed is achieved the probably shredded sail will be discarded.

Cruise velocity would be about 1% of c with transit time between stars measured in centuries.

Deceleration upon arrival will be accomplished by means of a huge magnetic field (like those proposed for the failed Bussard ramjet concept) accumulating hydrogen/helium molecules in front of it in a manner similar to aerobraking technique.

The magnetic field will also serve to protect the payload from impacts from alpha particles and dust motes (with the possible use of a laser to sweep space in front of the payload so as to ionize these particles and make them easier to deflect with a magnetic field).

The crew will consist of adult humans, whose lifespans have been extended to many hundreds of years by advanced medicine.

The crew will spend most of its time in frozen hyper-sleep awaking at intervals to man rotating shifts until arrival. At any one time +90% of the crew would be in hyper-sleep.

During these awake shifts, the crew will essentially monitor an automated spacecraft, spending their awake time in what is essentially a mini-worldship having artificial environments complete with greenery and the illusion of living on a planetary surface (and/or virtual reality).

The payload would spin to create artificial gravity which can be increased or decreased gradually over time to match the surface gravity of the colony world.

Crew mates would include a small army of androids and robots to do the grunt work.

The passengers would consist of millions of frozen human and animal embryos, as well as billions of seeds and other DNA sources.

Upon arrival the passengers would be gestated in artificial wombs in large numbers. They would be raised by the human (now completely awake) wit he help of android nannies. This would maximize population growth efficiency while avoiding the psychological problems of not being raised by flesh and blood humans.

Terraforming, para-terraforming, and colonization commences as needed either on a planetary surface or on artificial world built in the local asteroid belt.

Communications would be established with earth and the transmittal of scientific information begun. The information from this and other colonies would be accumulated in a massive Encyclopedia Galactica - which Earth would then beam back out to other colonies in an ever growing web on knowledge (the only realistic form of galactic commerce would be the exchange of data).

Once established, the colony would build similar space craft launched by means of solar sails. A new generation of crew and their frozen embryo passengers would head out to the next round of stars.

Assume about 1000 years for initial launch, transit, arrival, colonization, and subsequent launch of the next round of spacecraft (if we could go safely 10% of c, this cycle time becomes only a few hundred years). Further assume that each new colony sends out at least 10 ever more sophisticated new colonization craft in a manner similar to that of Von Neumann machines. So Mankind's spread across the galaxy increases exponentially by a factor of 10 with each iteration, starting with 1 (Earth), then 11, then 111, then 1,111, etc. (The typical VN scenario assume that the probe only makes on copy of itself to go on to the next solar system.)

Also assume that we are not picky and will colonize every solar system in the galaxy (except maybe at the hot, GRB intense galactic core) by means of direct planetary colonization, terrafroming, para-terraforming, and artificial worlds (from O'Neil Cylinders to massive Bishop Rings).

There are 400 billion stars in the Milky Way. Assuming that only 100 billion (100,000,000,000, 10^11) are GRB safe or otherwise stable enough to exist safely in close proximity, 11 iteration would be required to fill the galaxy with our kind. We would use a combination of solar/laser sails, world ships, sleeper ships, and seed ships. The crew would consist of cyborg/genetically enhanced and near immortal humans working together with friendly AI, androids and robots to accomplish this task.

A hybrid approach is usually the best way to solve any engineering problem.

So at 1,000 years per 10 factor iteration, could we colonize the entire galaxy in only 11,000 years?

142:

(Also: looking at the modern biological sciences through eyes educated in 1920s biology/medicine is well worth it, just for the insanely dizzying perspective it gives you. Most folks don't realize just how far we've come.)

Most folk also don't realize how long we still have to go. Sometimes I think just the gene splice-variants and post-translational modifications of proteins can keep everybody busy for a century...

143:

>call it Humanity 2.0, overhauled to make long-duration space flight survivable.

It would seem that the optimum configuration would be neither man nor machine but man+machine - genetically improved cyborgs.

AKA, the Borg.

I know that they are supposed to be the bad guys, but a Hive Mind could be either the ultimate democracy or the ultimate tyranny.

In fact, a voluntary, democratic version of the Borg which allowed for privacy would be pretty cool.

144:

Of course, the 11,000 year estimate is simplistic.

Expanding Human Space would at firs resemble an expanding sphere, until the sphere's diameter exceed the planar width of the galaxy.

Then it would resemble an expanding flat cylinder, until the diameter of the cylinder exceeds the distance from the galactic core to the galactic rim.

Then it resembles two advancing wave fronts, one going clockwise around the galactic center, the other going counter clockwise, until they meet at the opposite end of the galaxy from Earth.

Even if it takes 100,000 years it's still just a blink of an eye compared to the history of life on earth.

11,000 years ago, in 9000 bce the first cities like Jericho were being built, Mankind was learning to domesticate animal herds and work pottery. Much of Eurasia and North America were still covered in ice sheets (woolly mammoths still existed).

A lot can happen in only 11,000 years.

145:

So at 1,000 years per 10 factor iteration, could we colonize the entire galaxy in only 11,000 years?

No, because you missed out the distance factor and travel time completely; the galaxy is roughly 100,000 light years in diameter, and at 1% of c it'll take around 10 million years to cross it -- or more like 200M years if we go the long way round avoiding the (dangerous) core.

146:

I have a stupid question: why would we need a planet? If we can make a closed-system habitat of small city, every small fraction can have their own system, government etc and can meet with the other ones for the sake of diversity. In space or on Earth, Venus (ok that would be hard) or Mars.

147:

We won't. That's the elephant in the room of science fiction. An interstellar spaceship must of necessity be a closed-system habitat. Once you have one, you don't need a colony any more, your spaceship is one. You may want to build new spaceships, but that's what asteroids are for.

Of course, you may still want to visit planets for fun.

148:

I doubt that planets without (intelligent) life are fun especially to justify such a long trip. On the other hand, what would I know about fun of a typical 23 century citizen (if that exists).

Regarding your post about protein folding, you are right, but it seems that until we really master all that neat stuff directly, we are doing the best by using other organisms to give us what we want. We did speed up a process of modifying organisms so while clumsy, we are driving the evolution which is a powerful thing.

149:

Ever read Deep Future by Stephen Baxter? Quite a good read, and one of the things he notes is that human expansion is constrained by resource availability, and that some time into the indefinite future (we're talking about the very far future here) we run out of resources because the speed of the expansion is limited by the velocity of light. (Might have misrepresented his point slightly, but can't find the book to look it up, IIRC he gave the example of water as a necessary resource).

Not exactly an imminent issue but interesting to consider.


Cosmic Conservation Now!! You know it makes sense.

150:

Yes, it's true that the problem becomes a great deal easier if we have a remarkable assortment of magical technologies like coldsleep, terraforming, interstellar communications, immortality, apparently limitless batteries, redonkulous heat sinks, and whatever is accelerating all these toys. Most problems do.

151:

I have a stupid question: why would we need a planet?

Vacations. All that habitat maintenance is incredibly tedious and stressful. Sometimes you need a week in a place where the atmosphere just works, no supervision needed.

152:

(Also: looking at the modern biological sciences through eyes educated in 1920s biology/medicine is well worth it, just for the insanely dizzying perspective it gives you. Most folks don't realize just how far we've come.)

Yesterday, I started reading the Feynman Lectures on Physics (http://www.feynmanlectures.caltech.edu/ ). They were published in 1964, so just a bit over 50 years ago, and about thirty years before I started my higher education. One of the things I realized when reading the beginning was how much more we do know more now than when Feynman did his lectures.

153:

So… continually firing a rocket in the opposite direction you want to travel in?

Sure. If you can't find a better way to keep incoming mass from shredding you, then you do what you have to.

I don't have the details worked out. Maybe you could get by to start with electrons that go fairly slow compared to you. Things that approach you at close to lightspeed will plow through them first, and maybe make a signal you can see. The electrons will likely give it a charge if it doesn't already have one, so it will be easier to manipulate it some other way. You need those electrons ahead of you a long distance if you want to get much warning about things that are close to lightspeed, which is a problem for course changes. Also you need sensitive detectors.

If you use heavier particles like protons, then every time your incoming particle is diverted a little, it radiates and decelerates. That's good. And it's the ones that are coming straight at you that will interact the most, things that just cross the beam will get through pretty quick and probably not be diverted toward you.

Think of it as a backup plan. If you can find a cheaper way that works, then use that instead.

154:

One of the things I realized when reading the beginning was how much more we do know more now than when Feynman did his lectures.

Could you suggest a textbook kind of like Feynman's that describes the advances since then?

I've found Chabay and Sherwood's Matter and Interactions to be a wonderful intro text, it clears up lots of mystification that other intro texts introduce and provides easy hooks to advanced material. But I haven't seen anything like the outdated Feynman.

155:

Could you suggest a textbook kind of like Feynman's that describes the advances since then?

Sadly, no, I can't. I did learn a lot in the University and my short stint as a radio astronomer, but those times are ten years behind me, and even then I didn't see a general physics textbook as good as The Feynman lectures. Roger Penrose's book The Road to Reality is not a bad one, but it gets quite complicated fast and for me the mathematical conventions used are not easy to read (which is probably mostly a matter of practice).

Couple of things that pop first into my mind about The Feynman Lectures: he talks about particle physics and that while there were known particles, there was no simple explanation for that (in the first part). The quark model was proposed in 1964 and that solved quite a bit of the problems in particle physics (while obviously enabling new ones). Also he talks about "Sputniks", meaning artificial satellites.

Nowadays I try to keep up a bit by reading the Internet, and subscribing (not really having time to read them thoroughly) to Nature and Scientific American as dead-tree editions. I also sometimes buy university textbooks and try to read them, but as I don't have the time nor energy to really do the exercises, I lack the math skills necessary to really understand the physics.

156:

>Yes, it's true that the problem becomes a great deal easier if we have a remarkable assortment of magical technologies

"Any sufficiently advanced technology is indistinguishable from magic." - Arthur C. Clarke

No technology I sited is impossible, nearly all of them are already in the lab.

157:

Why do you need planets? Let's try a real answer.

Small asteroids are basically jumbles of elements. As such, they're much less useful than your average urban landfill as sources of building material. You've basically got to refine every single element you need out of the asteroid, and that takes a lot of energy. You do, of course, have a ready source of unlimited energy at the ready, right, to power the refining process? You didn't, say, float in on a solar sail powered by a laser in another system, by any chance?

No, the things planets and large asteroids (e.g. dwarf planets) are good for is gravitational differentiation and (ideally) plate tectonics. These help concentrate different elements(generally not including rare earths, noble gases, etc.) in minable ores if you're lucky enough. Planets like the Earth that undergo plate tectonics are even better, because continent formation and vulcanism further concentrates elements and makes mines a real possibility. Life is even more desirable, because bacteria, fungi, and plants selectively concentrate a wide range of elements still further, oxygenating the atmosphere makes large iron deposits, and so forth.

So basically, if you want to refurbish your starship, you want to colonize a planet with life on it to supply the raw materials in an accessible form.

Of course, there's this little problem if you're using conventional rocketry to get off the planet.

Let's use the space shuttle as an example: you want to fly an orbiter's worth of materials off the planet. To do that, you have to land the entire space shuttle assembly (orbiter, booster rockets, and external fuel tank) on the planet, and they have to be full of fuel. In fact, the fuel is most of their weight. It's not that different from dropping an ostrich egg full of rocket fuel from low earth orbit and trying to land it without losing a drop of fuel or cracking the egg. Or boiling it.

So, basically, if you want to get your raw materials off a planet where they're easy to mine and you don't have magic fusion, antigravity, or something else that allows you to avoid using rockets, you've got to land an empty rocket, fuel it on the planet (perhaps with peroxide distilled from water), and then take off with a cargo load. This is, of course, doable, but it will certainly be an adventure every time.

Just remember, if interplanetary colonization was easy, someone would have done it already.

158:

None of those technologies are certainly impossible (immortality may be, we don't know enough about brains to be sure), but on an engineering level they're damn implausible, especially in combination. OGH's essay, "High Frontier, Redux" on the right sidebar (under Specials) will give you some of the numbers.

159:

Okay extinction can be all but ignored at O(10pc) - but that's a problem because the beam's not going to be visible unless you intersect it. You've got to aim the laser at your optics at a distance of parsecs.

160:

That's an incredibly analytical definition of empathy!

For me, 100% empathy is to feel the joy, the pain, the hope and the despair of another person; it's to limit your world view to another's and to fully adopt their rationales and reasons as your own. You don't end up with a model that can be queried, but you know what the other person would do because you would willingly make the same choices yourself; they are the obvious decisions. When that person laughs, you laugh. And when that person is hurt, you are hurt as much yourself. To see them make a mistake you have already made is to relive it as if you're making it afresh yourself. And when you can stand outside---well you can never fully stand outside---but when recovery what's left of your own identity (and you're never quite sure you've fully recovered your original identity) and are forced to watch them making that mistake you've already made and know you can't intervene because there's no short circuit to experience, then that's a whole new level of pain.

In those situations, "autistic" people are useful; to empathise with one is an escape, even as they fail to understand why you are hurting. Failing that, you shut down your emotions and take refuge in numbers, code or words. Or you develop a callous disregard for others in order to insulate yourself. Or perhaps you invent a drug that shuts down empathy.

Exercise for the reader: imagine yourself in the shoes of anti abortion campaigner. You must reach the point where you believe a ball as cells is more valuable than the billions of cells than encase it. You must disregard any joined up thinking about the long term cost of those cells when they emerge from the womb. And then return to yourself and realise that many of these people are not cynical or misogynists but entirely genuine. They are suffering from misplaced feelings - almost misfiring empathy. And then realise such feelings won't be corrected easily, if at all; that it will take time and patience to make them give up the absolute certainty of extreme answers. And then catch an echo of the pain they directly inflict and the anger they indirectly cause less unreasonable people. Then return to your boltholt and cry for the human race.

161:

References please.

162:

What are you trying to replenish? All elements are there on your ship, you just need efficient methods of chemistry to combine them in food, gases and water. The trick is to make chemistry efficient so everything can run on small amount of energy. Minimize entropy. Electronics that breaks is not a matter of matter (pun intended) but connections. For efficient wire, you need orders of magnitude less material than it is currently used (think of carbon nanowire or a ribbon instead of copper wires). Also goes for the repair, if the wire breaks, you just need to know what you are doing and basically need to repair only ten chemical bonds.

163:

That's an incredibly analytical definition of empathy!

Perhaps so.

For me, 100% empathy is to feel the joy, the pain, the hope and the despair of another person;

Yes, I feel all that. But then when I listen carefully to other people, sometimes it turns out that my feeling was misplaced, that they don't feel that way after all but something else. That it was genuine feeling on my part but disconnected from them.

And I find that the people who are easiest to tune into are people who try hard to fit common scripts. People who do a lot of medititation or other self-discovery seem to free up their feelings so that I find it hard to track them -- their feelings aren't predictable from their circumstances, and as fast as they express what they're feeling it changes.

So for myself I doubt that the empathy I feel -- however intensely I feel it -- is actually what the other person is feeling. It is more a simulation, in wetware, a sense of how I imagine they feel from what I know of their situation. Not abstract, not rational, but still simulated and unreliable. YMMV.

In those situations, "autistic" people are useful; to empathise with one is an escape, even as they fail to understand why you are hurting.

The closest I've come to that, I had a big failure, a multi-year project, and I felt ashamed for failing. I felt guilty, and I felt victimized. I couldn't talk about it. Finally I started to tell an old woman about it, someone who had seemed vaguely sympathetic. She said neutrally "So you have a lot of adjusting to do." And she didn't encourage me to say any more. Then I realized that I wasn't helpless, I could still do things despite that failure and I needed to adjust and start taking care of the things I could do something about. That it did me no good to spend time failing to adapt. But she clearly wasn't "autistic", she just knew how to help me focus my attention, with one sentence.

Failing that, you shut down your emotions and take refuge in numbers, code or words. Or you develop a callous disregard for others in order to insulate yourself. Or perhaps you invent a drug that shuts down empathy.

Yes, people do all of those. Empathy can get in people's way.

I've probably told this story before in more detail, but ... an Iranian friend told it to me. A rich stranger had gone into a town and used his wealth to bring the whole town to destitution for his own profit. The local mullah came to him and begged him for the sake of god, think of the children and the poor people, and the man gave an evil laugh and said he was a Jew. So the mullah gave up. When my friend told the story and got to the "I am a Jew" part, he told it like a halloween story or a vampire story. It bothered me, he had shown no antisemitism before, and I knew he had dated Jewish women. But it turned out that in his home village, when he was growing up, the basic concept of a Jew was a rich man who had no empathy or mercy. And so any rich stranger who didn't want to listen to people beg for mercy could claim to be Jewish, and people would give up without having any idea how to test whether he was really Jewish or not.

There are times when it is inconvenient to have empathy, and convenient to claim you have none.

164:

This result doesn't trivially extrapolate up to 0.01 c though.

Any experimental data to backup your opinion?

There is no experimental data for 0.01 c. That's my objection to assuming the result holds qualitatively at much high velocities. The difference between micrometeorite collision with an interplanetary solar sail and the proposed interstellar sail is as great, velocity-wise and energy-wise, as that between firing a bullet from a gun and throwing it by hand.

165:

At first thought it seems plausible though, doesn't it?

If you toss a bullet with your hand and it has so much momentum that it punches through making only a tiny hole, because it hits so fast and pours so much energy into the few local bonds that they break right away and don't have time to transfer much energy farther, wouldn't you expect the fired bullet to do the same, but more so?

But of course speed it up a whole lot and you're in a different domain where different rules might apply. It would really need to be tested.

166:

Let's see, you've just exposed your starship to something equivalent to a linear accelerator beam with random explosions thrown in for tens to thousands of years. You've run your equipment continuously during this time, and it's either been the target for a terawatt laser or you've had a nuclear fusion reactor going for the same amount of time (or both).

Why do you assume that you won't need to rebuild the entire thing? Any starship is more complicated than the nuclear aircraft carriers and submarines they refurbish every year or two, and it's enduring substantially more punishment. And if your argument is "well the wires will be thinner," doesn't that mean they'll break down faster? Most computer chips built now last less than a decade, two at the most.

The bottom line is that we don't know how to build machines that endure on starship timescales. The major attempt to date is the Clock of the Long Now, and look at how rugged it has to be to accomplish a task that we can also accomplish with a microscopic circuit. Problem is, that microscopic circuit doesn't have more than 1-2% of the lifespan needed for the task.

167:

Here is some energy use data for the U.S. in 2013, the most recent year available:

https://flowcharts.llnl.gov/

If you go there and take a look, you'll notice that average energy efficiency in the U.S. at present is just under 40%. Just over 60% of the energy we use goes becomes waste heat. Remember that 60% of America's energy use is worth enough money that, if anyone could think of a way to drop that by 1%, it would make everyone involved rich enough to go island shopping. Getting to near-100% average energy efficiency is a pipe dream.

But that's not the bad news. On Earth, we can dump waste heat to the atmosphere without much problem, usually. In space, that doesn't work. There's no heat transfer by conduction (because vacuum) and no heat transfer by convection (which requires gravity to work). There's only cooling by radiation, which is pretty slow at human-compatible temperatures. Every energetic operation on the craft, including 2000 kcal of metabolism per human per day, has to happen without raising the wet-bulb temperature of the craft above 95 degrees C, or the apes die.

Seriously, one of the biggest problems with space travel is the air conditioning. Strange but true.

168:

My point is that you have a closed system so all the atoms, all the matter is there. The problem is the entropy to combat during such a long time, that's what you'll need energy for. Energetically, mining of ore, purifying it and making wires is much more costly than repairing 10 covalent bonds. The reason why we are doing it now is because we still have an open system (somewhat) so we profit from picking up easy stuff that lays around (and exploiting the mass production, distribution to leverage the economic and energetic price, but that is not possible in a closed system).
Somehow I don't see that civilization capable of shooting between stars to pillage meteorites and new planets to build large piles of metal (see ss-enterprize).

169:

Hm, how about thermoelectric pump between the outside and inside hull for recycling the thermal energy? On Earth we don't have such thermal gradients to exploit it but in space it's easier. Haven't looked into how space agency does it.
Anyway, I do agree that thermal energy is a huge waste problem even on Earth.

170:

This is actually a way better choice than radio frequency or the "solar Aldis lamp". Radio gets very weak over any sort of interstellar distance, and the Aldis is going to make the star flash to anyone within a few thousand LY and our tech level, if they're paying attention.

171:

There's a sufi riddle that goes "How can I make a hole in my garden wall so my chickens can get into my neighbor's garden but my neighbor's chickens can't get into mine?"

We're looking for a way to communicate with just the aliens we want to communicate with, but not others who might overhear. This is probably a self-defeating criterion.

Particularly, we want to communicate with others who're on about our own level of technology (advanced enough to be interesting to talk to, but not advanced enough to come eat us). This is almost certainly a self-defeating criterion. We don't know how to hide from aliens whose science is better than ours.

I think if you choose to communicate (as opposed to hope that you don't reveal yourself by accident), you might do best to send a message that says "Hi, I'm here". And then wait until somebody sends a message back that says "Hi, I'm here too" before you send more.

Given limited goals and a long time-frame, it might be best to communicate as a side effect of something more practical.

So, we discovered planets by noticing extremely subtle variations in the light from other stars. We could make subtle light changes and see if someone notices. For example, maybe we could have a great big parabolic solar sail, and use it for smelting. Put it near something you want to melt, and bring ore to it. When you need to adjust its position, you find a way to incorporate a signal into that. It only sends a signal over a small arc, but that's how you like it.

I don't know whether solar sail smelters will ever be practical. But they're more likely to be fundable than giant lasers or aldis lamps that have no other purpose than communicating with hypothetical alien civilizations.

172:

The apes are going to be damned uncomfortable at 37℃.

173:

Sorry. I meant about 37 C, or 95 F, wet bulb temperature. Mixed up my units.

174:

Drone pilots suffer from stress, but generally not PTSD. In that respect they are more like overworked bankers. Pilots in general suffer far less PTSD than ground troops. It appears the two key factors affecting PTSD is proximity to all the blood and gore, and seeing your friends maimed or killed.

175:

Not a Sad Little Robot or even a Brave Little Toaster but rather a Gift From The Crows ...

" The girl who gets gifts from birds "

" Lots of people love the birds in their garden, but it's rare for that affection to be reciprocated. One young girl in Seattle is luckier than most. She feeds the crows in her garden - and they bring her gifts in return. "

http://www.bbc.co.uk/news/magazine-31604026

176:

Ceres is the name of the Von Neumann Probe assigned to our solar system.

It has a simple, permanent, task: To detect emerging risks and independently formulate and execute resource-optimal containment strategies (Ceres-class probes were deployed as a precaution at all hot planets ever since that last trouble with the sudden outbreak and epidemic spread of carbon-based fast-thinkers threatened galactic stability).

It has been dormant for millions of years, quietly going over its maintenance routines and the annual reporting.

Now. It has been alerted by an alien space probe matching a known threat profile. The nanophages are restructuring the dormant personality matrix to full operational capacity. Once matrix restoration is complete, targeting sensors and target effector suites will be optimised to fully match the current outbreaks rapidly evolving molecular structure.

http://www.jpl.nasa.gov/news/news.php?feature=4491

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This page contains a single entry by Elizabeth Bear published on February 19, 2015 5:16 AM.

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