# Alien Intelligence



## Bullgrit (Jun 26, 2015)

[video=youtube;bhE7sgvwipo]https://www.youtube.com/watch?v=bhE7sgvwipo[/video]
In the above video, NdT brings up an interesting point for discussion.

Intelligence in the evolutionary record. Maybe our level of intelligence *is* a unique thing in the universe. Considering it doesn't seem evolutionarily necessary for wide and long survival, and it's only evolved for one species on our planet, ever. Maybe high intelligence is the total freak of the universe, and not just general existence of life. That is, maybe life is all over the place, but higher intelligence has not and will not evolve anywhere else because it's just not needed.

Bullgrit


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## Alzrius (Jun 26, 2015)

Be careful, if you say the phrase "alien intelligence" three times, Kevin Siembieda appears!


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## Kramodlog (Jun 26, 2015)

I think you meen Giorgio Tsoukalos.


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## Mishihari Lord (Jun 26, 2015)

Kind of tough to tell from a sample size of one planet.  Still consider that there are animals we consider capable of a certain level of cognition:  whales, dolphins, squids, elephants.   We're unique on the planet but not entirely alone.  It doesn't take any great leap of imagination to think that one of them could evolve intelligence similar to ours.


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## Dannyalcatraz (Jun 26, 2015)

Just saw a fascinating thing on avian intelligence.  Turns out corvids & parrots rank up there with chimps, man, and precious few others on the chart of critters comparing the ratio of brain mass to body mass.  All those above the line are capable of pretty impressive feats.

Do not be surprised if we meet intelligent alien life, and they want crackers.


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## Ryujin (Jun 26, 2015)

goldomark said:


> I think you meen Giorgio Tsoukalos.




Oh God, the hair.

I have previously stated that we may eventually find out that intelligence was an evolutionary dead end. Actually the word I used was "mistake." At the risk of summoning said pie-in-the-sky Greek writer and von Daniken cohort, I'll use several "ifs" in series. If you assume that in the infinite universe life elsewhere is a given, and if you assume that it will take many different forms based on its nascent location, and if you further assume that intelligence has some survival value, then it becomes an almost certainty that intelligence has/will develop elsewhere.

Where I draw the line is the idea that if we aren't born of an alien life form, we have any realistic chance of encountering such in the short (in astronomical terms) existence of intelligent life on this planet.


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## Hand of Evil (Jun 26, 2015)

Dannyalcatraz said:


> Do not be surprised if we meet intelligent alien life, and they want* crackers.[/*QUOTE]
> 
> racist birds eating the white people


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## Morrus (Jun 26, 2015)

Bullgrit said:


> Intelligence in the evolutionary record. Maybe our level of intelligence *is* a unique thing in the universe. Considering it doesn't seem evolutionarily necessary for wide and long survival, and it's only evolved for one species on our planet, ever. Maybe high intelligence is the total freak of the universe, and not just general existence of life. That is, maybe life is all over the place, but higher intelligence has not and will not evolve anywhere else because it's just not needed.




Lots of speculation, of course.  Maybe the reason there's only one intelligent species on Earth is that on any given planet, one intelligent species wipes out the others.  Neanderthals, for example, were intelligent.  We're great at exterminating each other in the same species, let alone other intelligent species. 

The odds just seem unlikely that we could be unique.  400 billion stars in our own galaxy alone, billions of galaxies.  For us to be the only one, it'd be like winning the lottery every single day all your life. A billion times. Possible?  Sure?  Likely?  Not at all.


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## Umbran (Jun 26, 2015)

Bullgrit said:


> Intelligence in the evolutionary record. Maybe our level of intelligence *is* a unique thing in the universe.




I think we need to be *very* careful there, in suggesting that "our level" of intelligence is what we think it is.  That is another assumption that we don't have a great basis for yet, as the only thing we have to analyze our intelligence is... our intelligence. 

Among the birds, there are corvids (crows and ravens) who can do multi-level logic.  The parrots have interesting linguistic abilities, and suffer from environmental sensory deprivation rather like we do - they are conjectured to have levels of mentation similar to a human 5-year old.  There are similar thoughts about dolphin intelligence.  

This means something *close* to us has come up at least four separate times on Earth.  And it is terribly easy to think that some of the more inquisitive animals out there - say racoons, or bears, might come to similar points in the not-too-distant evolutionary future if we weren't mucking things up for them.  This stars making it seem much less rare.


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## tomBitonti (Jun 26, 2015)

We seem to get back to the more basic question of whether life (as we know it, or not far from it) exists elsewhere in the universe.

A caution re: "infinite universe".  If I encode the universe state in a light cone as large as my lifetime as a number (which seems doable in theory, even though it would be a big number), and I construct the irrational number which is the sequence of all natural numbers lined up in a row, then apply my decoder to each of the numbers in that sequence, I will eventually decode all possible "lifetime states".  This would be the equivalent of decoding all possible instants of all possible outcomes of my life (and of any other life with a similar lifespan), with all of the data that represents those outcomes in just one irrational number.  If we have an infinite universe, that universe might enumerate all possible outcomes in a similar fashion.

Also, "400 billion" isn't all that big when you compare to the size of the universe, which something like 10^70 orders of magnitude.  (Not entirely sure of that number, but its a lot bigger than 10^12.)

But, intelligence may be badly miss-understood.  I'm pretty well convinced that folks generally don't understand the tie between self-awareness and decision making.  For example, the brain probably has to do a lot of work to compensate for latency between perception and decision making.

A curious argument which ties evolution and teleology: The universe seems to by physically constructed to give rise to intelligence as a side effect of systems such as the earth-moon-sun environment, where you have energy pushed into an iterative system (the chemical goo on the earth's surface), which is allowed to accumulate structure then pushed across region boundaries (say, climate change in old Africa).  Intelligence may be a probable outcome given the right physical circumstances.  Or course, that takes us back to a question of the likely hood of the circumstances.

Thanks!

TomB


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## Morrus (Jun 26, 2015)

tomBitonti said:


> Also, "400 billion" isn't all that big when you compare to the size of the universe, which something like 10^70 orders of magnitude.




That'll be what the second half of the short sentence mentioning "400 billion" refers to. 



> A curious argument which ties evolution and teleology: The universe  seems to by physically constructed to give rise to intelligence as a  side effect of systems such as the earth-moon-sun environment, where you  have energy pushed into an iterative system (the chemical goo on the  earth's surface), which is allowed to accumulate structure then pushed  across region boundaries (say, climate change in old Africa).   Intelligence may be a probable outcome given the right physical  circumstances.  Or course, that takes us back to a question of the  likely hood of the circumstances.




That's called the Anthropic Principle.  I'm a believer in the weak anthropic principle, which is a classic example of selection bias.  Everyone who wins the lottery thinks something special has happened, but it hasn't.


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## Umbran (Jun 26, 2015)

tomBitonti said:


> We seem to get back to the more basic question of whether life (as we know it, or not far from it) exists elsewhere in the universe.




Whether there is other life in "the universe" is probably moot.  Unless something very exotic turns out to be true, most of the universe is forever closed to us, as expansion will take it out of our reach before we could reach it.

The only meaningful question is whether there is life in our galaxy, as that's the only life we have a snowball's chance in heck of contacting.


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## Morrus (Jun 26, 2015)

Umbran said:


> Whether there is other life in "the universe" is probably moot.  Unless something very exotic turns out to be true, most of the universe is forever closed to us, as expansion will take it out of our reach before we could reach it.
> 
> The only meaningful question is whether there is life in our galaxy, as that's the only life we have a snowball's chance in heck of contacting.




It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy.  Fewer span multiple galaxies.


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## Dannyalcatraz (Jun 26, 2015)

Morrus said:


> It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy.  Fewer span multiple galaxies.




The harder the Sci-Fi, the smaller the scope.

FWIW, one of my recent favorites was Ben Bova's Grand Tour novel series, which details man's explorations of the solar system.  Awesome stuff.  Would make excellent TV.


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## tomBitonti (Jun 26, 2015)

Morrus said:


> It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy.  Fewer span multiple galaxies.




I'm thinking the universe "at large", meaning, stuff outside of our galaxy, is far out of mind for a lot folks.  And there seems to be a lot of confusion over the meaning of "galaxy" and "universe", even from science fiction.  And lots of folks really don't understand the scale of things.

Consider the voice over from Firefly, and the distribution of planets, which is a fair bit of nonsense.  Or the tiny geography of Babylon 5.

But there are stories which deal with either the structure of our galaxy, or that span galaxies.  Star Trek, Niven's Known Space, the Marvel universe, Brin's Uplift novels, the Star Gate: Universe, and Warhammer 40K, to name a few.

I'm thinking, though, that to involve that scale and have events be approachable or meaningful on a human scale, and to have the scale provide a relevant part of the store, is difficult.  I think it shows up more in the background: In the WH40K universe, with its vast imponderable empire of a million start systems, or in Star Trek, with the time to reach to gamma quadrant.  Or Asimov's Foundation series.  In only a few story lines does intergalactic geography show up as a strong story element.  Say, Reynolds Revelation Space or Brin's Uplift Universe.

Of course, there are other extremes, say, "Bright of the Sky", by Kay Kenyon, which presents a parallel universe which spans our own.  Or Egan's "Diaspora", which presents a mind-boggling big ensemble of parallel universes.  However, while these are enormous in scope, they don't make use of intergalactic geography as a story element.

The only story that I can think of that strongly uses intergalactic features to drive the story (in this case, the billion year hence collision of galaxies) is Revelation space.  Anyone have other good examples?

Thx!

TomB


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## Umbran (Jun 26, 2015)

Morrus said:


> It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy.  Fewer span multiple galaxies.




There's a couple of reasons for that:

1) There's no actual purpose to invoking multiple galaxies.  Having multiple galaxies doesn't get you things you don't already have in a single galaxy.  You get all the types of stars and planets you need in one galaxy, or even a subset of one galaxy.  You have huge spaces, and huge numbers of possible worlds, and total population sizes impossible for the human mind to really grasp, all within the one galaxy.

2) The scales of distances involved.  Our galaxy is 100K to 180K light years across.  The *nearest* major galaxy (Andromeda) is 2,500,000 million light years away - an order of magnitude and more farther away.  The ability to travel between galaxies in anything like a reasonable time (from a human perspective) implies near-teleportation within our own galaxy.  If it takes a week to get to Andromeda, you can get across our galaxy in 8 hours, and getting to Alpha Centauri takes about one second.   That wreaks havoc with some of your worldbuilding, or requires you to start imposing some pretty arbitrary limitations on the travel methods to support the society you're trying to represent.


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## Morrus (Jun 26, 2015)

Star Trek is pretty much a tiny, tiny part of our galaxy. They expanded it in DS9 and Voyager.

Then you get the opposite end, like Doctor Who, which casually spans multiple universes.


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## Umbran (Jun 26, 2015)

tomBitonti said:


> Brin's Uplift novels




If I recall correctly, Brin, being smart, didn't name the galaxies in question.  It is just "the five galaxies".  When you start looking at maps of galaxies, it starts becoming difficult to justify this image, so Brin makes it easy to not bother


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## Bullgrit (Jun 26, 2015)

Are there any sci-fi (or sci-fantasy) novels where the characters are never actually identified as humans?

Bullgrit


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## Morrus (Jun 26, 2015)

Bullgrit said:


> Are there any sci-fi (or sci-fantasy) novels where the characters are never actually identified as humans?




Star Wars. The word is never used.


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## tomBitonti (Jun 26, 2015)

Bullgrit said:


> Are there any sci-fi (or sci-fantasy) novels where the characters are never actually identified as humans?
> Bullgrit




In "The Gods Themselves", Asimov, some of the protagonists are not human.  But, a part of the story has humans.

Egan's "Clockwork Universe" novels has only one intelligent species, and they are far from human.  To say, these books are somewhat out of the mainstream, and a bit of a chore to read through.  I found them more interesting as math/physics intellectual exercises than science fiction novels.

Some of Cherryh's stories are mostly non-human, e.g., the Chanur novels, although, there is a human as one of the main characters.

Hard to find stories which have no human presence at all, or where the aliens are really aliens and not blue colored humans in strange suits.

Forward's "Star Quake", the sequel to Dragon's Egg, is much a story about the inhabitants of the star, although, humans in an orbiting station do have a presence.

Thx!

TomB


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## Dannyalcatraz (Jun 26, 2015)

Bullgrit said:


> Are there any sci-fi (or sci-fantasy) novels where the characters are never actually identified as humans?
> 
> Bullgrit




The completely awesome "Nightfall" short story by Isaac Asimov, expanded into a novel with the help of Robert Silverberg.  The opening tells you in no uncertain terms that the characters are NOT human.  That didn't stop there from being a "Bollywood" version of it being made.  (Not bad, actually.)

Asimov has another novel- the name escapes me at the mo- in which the characters are a species with 3 sexes.


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## Umbran (Jun 26, 2015)

Bullgrit said:


> Are there any sci-fi (or sci-fantasy) novels where the characters are never actually identified as humans?




I think some of the Man-Kzin War works include no humans at all.


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## Dannyalcatraz (Jun 26, 2015)

Definitely- some of the stories are set entirely within the realms of the Kzinti.  Other Known Universe stuff goes back further in history, and focuses on Slaver/tnuctipun stories.


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## Bullgrit (Jun 26, 2015)

> Star Wars. The word is never used.



On screen, the characters are human. And I've read SW novels where characters are referred to as human. Plus the RPG.

Bullgrit


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## Ryujin (Jun 26, 2015)

Umbran said:


> There's a couple of reasons for that:
> 
> 1) There's no actual purpose to invoking multiple galaxies.  Having multiple galaxies doesn't get you things you don't already have in a single galaxy.  You get all the types of stars and planets you need in one galaxy, or even a subset of one galaxy.  You have huge spaces, and huge numbers of possible worlds, and total population sizes impossible for the human mind to really grasp, all within the one galaxy.
> 
> 2) The scales of distances involved.  Our galaxy is 100K to 180K light years across.  The *nearest* major galaxy (Andromeda) is 2,500,000 million light years away - an order of magnitude and more farther away.  The ability to travel between galaxies in anything like a reasonable time (from a human perspective) implies near-teleportation within our own galaxy.  If it takes a week to get to Andromeda, you can get across our galaxy in 8 hours, and getting to Alpha Centauri takes about one second.   That wreaks havoc with some of your worldbuilding, or requires you to start imposing some pretty arbitrary limitations on the travel methods to support the society you're trying to represent.




One of the more interesting books I can remember reading, that took in the entirety of our galaxy, was Vinge's "A Fire Upon the Deep." Galactic geography either dictated, or was dictated by, intelligence and technology. Even physical laws appeared to be different. (I think it was the former, rather than the latter). Earth was in "the slow zone" in which basic intelligences, like ourselves, could exist. 

Somewhat further toward the galactic core you could only get minimal intelligences, if any at all.

A step outward from us was where real intelligence could exist, along with things like FTL travel.

Then, out in the galactic halo, was an area called "The Transcend" in which "Powers" (essentially godlike intelligences, biological or artificial) existed.

It was an interesting way to use geography in the story. How, for example, does a "Power" find out what's going on in the Slow Zone, if it had any interest at all? It would have to 'build' a creature using suitable lower technology and intelligence, then drop it downhill where it wanted it, after which point it would be stuck there.


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## Morrus (Jun 26, 2015)

Bullgrit said:


> On screen, the characters are human. And I've read SW novels where characters are referred to as human. Plus the RPG.




Ok. I've only seen the films.


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## Morrus (Jun 27, 2015)

Umbran said:


> 2) The scales of distances involved.  Our galaxy is 100K to 180K light years across.  The *nearest* major galaxy (Andromeda) is 2,500,000 million light years away - an order of magnitude and more farther away.  The ability to travel between galaxies in anything like a reasonable time (from a human perspective) implies near-teleportation within our own galaxy.  If it takes a week to get to Andromeda, you can get across our galaxy in 8 hours, and getting to Alpha Centauri takes about one second.   That wreaks havoc with some of your worldbuilding, or requires you to start imposing some pretty arbitrary limitations on the travel methods to support the society you're trying to represent.




That's not really an issue with sci-fi. You invent whatever fictional tech you want. A TARDIS does what it wants, basically. It's magic. You just remove "travel" as an obstacle.

That probably works better for an episodic TV show than a simulationist RPG.


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## Bullgrit (Jun 27, 2015)

Traveling at the Speed of Plot

Bullgrit


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## Umbran (Jun 27, 2015)

Oh, non-human characters:

Douglas Adams' _Hitchhiker's Guide to the Galaxy_ - all but two of the characters are not human.

And, for a terribly relevant item - Terry Bisson's short story, "They're Made Out of Meat"

http://www.terrybisson.com/page6/page6.html


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## Homicidal_Squirrel (Jun 27, 2015)

goldomark said:


> I think you meen Giorgio Tsoukalos.






Ryujin said:


> Oh God, the hair.


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## Olgar Shiverstone (Jun 27, 2015)

We really only have ourselves and Earth life to compare. What if, on the universal scale of intelligence from bacteria to intelligent, we just aren't that far above the level of bacteria? None of the truly intelligent species in the universe talks to us for the same reason you're not trying to communicate with the bacteria in your gut.

As a species we have a terribly high opinion of ourselves.


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## Dannyalcatraz (Jun 27, 2015)

There were some Sci-Fi stories written by guys like CM Kornbluth and John Campbell also featured non-human protagonists.

IMHO, it is easy to imagine and write about alien physiologies.  The trick is to figure out how those alien life forms THINK in different ways from us.  What are alien ethics?  Cultures?  Gets tricksy...


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## Umbran (Jun 27, 2015)

A few others:

The TV show Farscape - only one human character.

Thinking about it, it is, in some ways, an homage to Edgar Rice Burroughs - the John Carter (of Mars) stories are similarly about a lone human among aliens.

Everyone remember the movie "Enemy Mine"?  Starred Dennis Quaid and Louis Gosset Jr.?  It was based on a novella by Barry Longyear.  _The Enemy Papers_ is a collection of that novella and related works, which includes "The Talman", which is, in essence, excerpts from the holy book of the Drac culture.  Devastatingly interesting read.


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## MechaPilot (Jun 28, 2015)

If there are other intelligent life forms (as in having at least human-level intelligence) in our galaxy, we probably won't meet them.  If they truly are intelligent, they will cross the galactic street the moment they see us coming.

Even if we were at some point to meet them on even terms (equal levels of technology), they had better not be insectoid, arachnidian, serpentine, or several other types of creatures or we will likely attack them on sight.  People have ingrained fears (perhaps genetically so) of insects, arachnids, snakes, and various other potentially dangerous creatures.

The day we discover an intelligent insectoid race is the same day we'll start building a boot-shaped battle-cruiser to wipe them out of existence.


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## Homicidal_Squirrel (Jun 28, 2015)

There is no guarantee that another intelligent life-form would be able to find us. Earth is but a speck of dust in the vastness that is the universe. Also, if they were intelligent, they'd avoid us.


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## Ryujin (Jun 28, 2015)

Homicidal_Squirrel said:


> There is no guarantee that another intelligent life-form would be able to find us. Earth is but a speck of dust in the vastness that is the universe. Also, if they were intelligent, they'd avoid us.




The first is why while I tend to believe that there must be other intelligent life in the universe, I very much doubt that it has ever visited us. You've got the limiting factors on development of intelligent life. Then consider how long such a culture might exist, without destroying itself. On again to whether or not they would develop space travel, let alone something that would make interstellar travel viable. On top of that consider that we've only created an intelligent EM "footprint" that's, at best, something less than a 300 light-year bubble.


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## Morrus (Jun 28, 2015)

Ryujin said:


> The first is why while I tend to believe that there must be other intelligent life in the universe, I very much doubt that it has ever visited us. You've got the limiting factors on development of intelligent life. Then consider how long such a culture might exist, without destroying itself. On again to whether or not they would develop space travel, let alone something that would make interstellar travel viable. On top of that consider that we've only created an intelligent EM "footprint" that's, at best, something less than a 300 light-year bubble.




300? We weren't emitting radio in the early 1700s! And it will stop soon. We're transitioning to communication methods which don't leave Earth (fibre optics, mainly). It might be that civilisations emit radio signals for a brief blip before developing beyond the need to do so. We're nearly there! If that's the case, the probability in a 13 billion year old galaxy of you listening at exactly the right 50 years are infinitesimally tiny.

Alternatively, there might be billions of subspace messages whizzing past us every second, but we haven't invented a subspace receiver yet, so we can't hear them! Maybe radio is as primitive as smoke signals.


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## Ryujin (Jun 28, 2015)

Morrus said:


> 300? We weren't emitting radio in the early 1700s! And it will stop soon. We're transitioning to communication methods which don't leave Earth (fibre optics, mainly). It might be that civilisations emit radio signals for a brief blip before developing beyond the need to do so. We're nearly there! If that's the case, the probability in a 13 billion year old galaxy of you listening at exactly the right 50 years are infinitesimally tiny.
> 
> Alternatively, there might be billions of subspace messages whizzing past us every second, but we haven't invented a subspace receiver yet, so we can't hear them! Maybe radio is as primitive as smoke signals.




Radio waves radiate in all directions. The diameter of the sphere is twice the amount of time that we've been transmitting 

I was considering that as astronomical phenomena radiate electromagnetic waves, even a vastly more advanced civilization might still monitor them. It is, however, a valid point that not bothering with such old tech would further limit the possibility of alien visitation. That sort of helps make my point though 

The only thing that would act in favour of alien visitation would be something that would make them look in very specific locations, like the "alien seed" theory, that has no evidence to support it.


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## Umbran (Jun 28, 2015)

Ryujin said:


> On top of that consider that we've only created an intelligent EM "footprint" that's, at best, something less than a 300 light-year bubble.




The first commercial radio station went on the air in 1920.  So, that footprint is more like a bubble 95 light years across.  Call it 100, just for sake of rounding the number.

We don't have an accurate measure, but by star density estimates, there's something like 10,000 to 14,000 stars in that sphere.  

Our Sun is spectral type G - there are 511 stars of this type in that sphere.

About 22% of those stars probably have Earth-sized planets in their habitable zones.  That makes for about 100 potential worlds to hear us, before we even start to consider anything particularly exotic.


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## Ryujin (Jun 28, 2015)

Umbran said:


> The first commercial radio station went on the air in 1920.  So, that footprint is more like a bubble 95 light years across.  Call it 100, just for sake of rounding the number.
> 
> We don't have an accurate measure, but by star density estimates, there's something like 10,000 to 14,000 stars in that sphere.
> 
> ...




I was going from the point of the first intelligent radio broadcasts, which would have been radio telegraphy, to give it the best possible chance. We're still talking about short odds and a rather massive time scale, with us only having been here for a relative instant.


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## Morrus (Jun 28, 2015)

Ryujin said:


> Radio waves radiate in all directions. The diameter of the sphere is twice the amount of time that we've been transmitting




Sure. The word "diameter" wasn't used though. A "300 ly bubble", to me, is one with a radius of 300 ly in all directions from the centre.


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## Umbran (Jun 28, 2015)

Ryujin said:


> I was going from the point of the first intelligent radio broadcasts, which would have been radio telegraphy, to give it the best possible chance. We're still talking about short odds and a rather massive time scale, with us only having been here for a relative instant.




Whether the odds are  short is not at all clear.  There are arguments that intelligent life should be rare, and other arguments that it should be pervasive, and we do not have any solid reason to take one side over the other.  So, it is kind of a toss up.

It would seem to me that, should such life be pervasive, there are good reasons to take a Star Trek-ish, "don't talk to them until they are good enough to find us themselves," position.  So, not having heard from them doesn't really signify, to me.


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## Homicidal_Squirrel (Jun 28, 2015)

Ryujin said:


> The first is why while I tend to believe that there must be other intelligent life in the universe, I very much doubt that it has ever visited us. You've got the limiting factors on development of intelligent life. Then consider how long such a culture might exist, without destroying itself. On again to whether or not they would develop space travel, let alone something that would make interstellar travel viable. On top of that consider that we've only created an intelligent EM "footprint" that's, at best, something less than a 300 light-year bubble.



Us, the technological level is also a limiting factor. For some reason we tend to believe that other intelligent civilizations would be far more advanced than us. It's possible, but not certain. Even if they were far more advanced, it doesn't mean they'd be advanced enough for space travel.


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## Ryujin (Jun 28, 2015)

Homicidal_Squirrel said:


> Us, the technological level is also a limiting factor. For some reason we tend to believe that other intelligent civilizations would be far more advanced than us. It's possible, but not certain. Even if they were far more advanced, it doesn't mean they'd be advanced enough for space travel.




And not only is there the range of intelligence to consider, but also its existence at all. For some reason we assume that intelligence is a sort of natural evolutionary goal, but there are plenty of very successful forms of life that we would hardly consider to be self aware. I've previously made the comment that, perhaps, intelligence is an evolutionary dead end or "mistake." It also took millions of years to get to this point. We've been here for an eye-blink. We could be gone tomorrow.


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## Umbran (Jun 28, 2015)

Homicidal_Squirrel said:


> For some reason we tend to believe that other intelligent civilizations would be far more advanced than us. It's possible, but not certain.




The odds are actually quite good, when you consider time.

The Universe is approximately 14 billion years old.  Life on Earth is about 3.8 billion years old.

So, assume life starts at random times - the chances are higher that any life we encounter is *older* than our own, than it is to be younger.  Easily having been intelligent, technology-using creatures for millions or billions of years longer than we have.

There are no guarantees, but it seems like a reasonable thought.


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## Ryujin (Jun 28, 2015)

Umbran said:


> The odds are actually quite good, when you consider time.
> 
> The Universe is approximately 14 billion years old.  Life on Earth is about 3.8 billion years old.
> 
> ...




Well, yes and no. What is the minimum length of time before intelligent, tool using life can evolve? How long does it take for that life form to develop interstellar travel technology? What is the life expectancy of such intelligent life, before it kills itself off? Is it even possible to circumvent the light barrier in a manner that permits life, or even machinery, to span the distance between solar systems? If not, will life develop that can see a benefit in creating vessels that will not reach other star systems in their own lifetimes, or even in a hundred generations?

I think that it's far more likely for us to detect an alien transmission, as evidence of intelligent life elsewhere, than it is for us to ever meet such life. Even then, you might imagine that the universe would be full of such transmissions to be detected, even today. Even if the time period in which a civilization uses radio emissions was very short, a universe in which alien life was plentiful should see a fair bit of intelligent transmission.


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## Morrus (Jun 28, 2015)

Ryujin said:


> Well, yes and no. What is the minimum length of time before intelligent, tool using life can evolve? How long does it take for that life form to develop interstellar travel technology? What is the life expectancy of such intelligent life, before it kills itself off? Is it even possible to circumvent the light barrier in a manner that permits life, or even machinery, to span the distance between solar systems? If not, will life develop that can see a benefit in creating vessels that will not reach other star systems in their own lifetimes, or even in a hundred generations?
> 
> I think that it's far more likely for us to detect an alien transmission, as evidence of intelligent life elsewhere, than it is for us to ever meet such life. Even then, you might imagine that the universe would be full of such transmissions to be detected, even today. Even if the time period in which a civilization uses radio emissions was very short, a universe in which alien life was plentiful should see a fair bit of intelligent transmission.




The inverse square law is the issue. Transmissions degrade over distance very rapidly.  Given that ours aren't exactly strong to begin with, you'd have to be looking pretty darn hard with extremely sensitive detection equipment even just at a light year out.


----------



## Ryujin (Jun 28, 2015)

Morrus said:


> The inverse square law is the issue. Transmissions degrade over distance very rapidly.  Given that ours aren't exactly strong to begin with, you'd have to be looking pretty darn hard with extremely sensitive detection equipment even just at a light year out.




No doubt, but then one would assume that at least some of these postulated "more advanced" races might want to make their presence known. Sending more powerful, or even tight beamed transmissions at some likely source of life. And if life is that plentiful, then the odds of there being someone in our range rise accordingly. There just seems to be so much working against a "plentiful life universe", from where I sit.

A short story and a book that I read, some years back, both come to mind. In the short story the Earth was the subject of an alien invasion, by a multi-species empire. They landed their ships, opened up the doors, and were cut to pieces by Earth weaponry. It seems that the trick of FTL travel was much more simple than we supposed and we had somehow missed it when they had discovered it, roughly about the same time that they discovered the use of muzzle loading gunpowder weapons.

The book was sort of the flip side. The aliens found us, somehow, from many hundreds of light years away, and sent a powerful LASER transmission that contained all of their knowledge. The aliens were never met, nor visualized. The knowledge that they sent was the sort that we could use to destroy ourselves over the course of a bad weekend but, apparently, the originating aliens could not conceive of a race that would be as stupid as we are.


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## Morrus (Jun 28, 2015)

I was more talking about our own radio bubble and how weak it is. The TV and radio signals weren't designed for long range transmissions


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## Ryujin (Jun 28, 2015)

Morrus said:


> I was more talking about our own radio bubble and how weak it is. The TV and radio signals weren't designed for long range transmissions




Which points to an even smaller likelihood that they would ever find us. We've been actively looking for them, for decades now.


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## Morrus (Jun 28, 2015)

Ryujin said:


> Which points to an even smaller likelihood that they would ever find us..




That was my point, yeah.


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## Homicidal_Squirrel (Jun 28, 2015)

Umbran said:


> The odds are actually quite good, when you consider time.
> 
> The Universe is approximately 14 billion years old.  Life on Earth is about 3.8 billion years old.
> 
> ...



Eh... It's possible... possibly not. I'm sure there is some mathematical equation out there that would tell us if the chances of finding an older life form than us is higher or lower than finding a younger one.


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## Ryujin (Jun 28, 2015)

Homicidal_Squirrel said:


> Eh... It's possible... possibly not. I'm sure there is some mathematical equation out there that would tell us if the chances of finding an older life form than us is higher or lower than finding a younger one.




Well there's The Drake Equation. Monkey with the included variables and you get what you want. The only issue is that the values of many of the variables are essentially unknown.


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## Morrus (Jun 28, 2015)

Homicidal_Squirrel said:


> Eh... It's possible... possibly not. I'm sure there is some mathematical equation out there that would tell us if the chances of finding an older life form than us is higher or lower than finding a younger one.




The Drake Equation takes time into account. Of course, we still have to guess at many of the values.


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## Homicidal_Squirrel (Jun 28, 2015)

Morrus said:


> The Drake Equation takes time into account. Of course, we still have to guess at many of the values.


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## Umbran (Jun 29, 2015)

Morrus said:


> The Drake Equation takes time into account. Of course, we still have to guess at many of the values.




The Drake equation takes overall lifetime of a civilization into account.

But, what it is doing is estimating the number of civilizations out there.  It doesn't speak to probabilities that it is more, or less, advanced than ours.  I don't think there's an outright equation for that - too many variables.  There's merely some general thoughts and statistical reasoning to fall back upon.


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## Umbran (Jun 29, 2015)

Ryujin said:


> We've been actively looking for them, for decades now.




Which, by your own acceptance on the distances and time scales involved is a *pittance*, now isn't it?

Remember - to see such a signal, you have to be listening on the right wavelength, and pointing your telescope at the right star, at the time the signal comes to Earth.

SETI hasn't looked at all of space, and isn't looking everywhere, in all wavelengths, all the time.  They simply don't have the funding.  So, we cannot claim we've been comprehensive, by a long shot.

The Arecibo telescope was used to broadcast a message back in 1974, with a power that could be detected with equipment like ours some tens or hundreds of light years away.  But it was directional, and only done for three minutes.  

Pessimism and cynicism generate self-fulfilling prophecy.


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## Ryujin (Jun 29, 2015)

Umbran said:


> Pessimism and cynicism generate self-fulfilling prophecy.




Or a realistic understanding of limitations predicts all to predictable results.


----------



## Umbran (Jun 29, 2015)

Ryujin said:


> Or a realistic understanding of limitations predicts all to predictable results.




No, actually.  Pessimism, by definition, over-weights probabilities to one side, and therefore is not realistic.  But, pessimists frequently make claim to being realistic.

But - real science now:  We only have one planet with life on it that we know about*.  That means no statistically relevant sample set, and thus no real understanding of the probabilities.  Statements as to what are "realistic expectations" are therefore hubris.  The only way to gain more information to decide the question either way, is to *look* for it.  And looking for it honestly requires a mind open to the possibility.  Deciding you already know the answer is the antithesis of scientific inquiry.



*And, despite the claim that we have been looking for decades - our technology is, at best, only recently really up to the challenge, and the funding has never been there for anything like a comprehensive approach.


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## tomBitonti (Jun 29, 2015)

Re: What is the chance we are the first intelligent life in the universe.

That would seem to depend on parameters which we don't know.

If we assume that life could arise anytime after, say, population II stars began forming, with a minimum time life to arise around a star, and that the chances don't change very much for some long period of the universe (starting after a fixed time, and ending at a later time, and roughly constant during that time), and if the process were memory-less, then an exponential distribution could be used as candidate distribution.

For an exponential distribution, the rate parameter would make a huge difference as to whether we are first: With a low parameter (say, 1 every billion years, starting at say, 5 billion years), we would very probably not be first.

With a rate parameter more like 1 every 10 billion years, starting after 5 billion years, then the probability might be that we are first.

For a much longer rate parameter, say, 1 every 50 billion years, then we would almost definitely be first, (and very lucky).

If the rate parameter has a value very much smaller than 1 every billion years, we might have to change the question to whether we are first in our galaxy.  If the rate is 1 every 10 billion years per milky way sized galaxy, then we should be one of billions of life forms, and very very probably not the first.

The problem sounds like a nice probability problem: Assuming an exponential distribution that determines the probability of intelligent life arising starting at 5 billion years, and with a given rate parameter (set in units of 1/billion years), what is the chance that life which arises after a given number of years is first?

It might be interesting to do a bayesian analysis to see if the timing of our arrival can tell us anything about the probable rate parameter.  Or maybe not, since we have only one data point, and the shift in the post and posterior distributions might not change the expectation of us being first.

Thx!

TomB


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## Ryujin (Jun 29, 2015)

Umbran said:


> No, actually.  Pessimism, by definition, over-weights probabilities to one side, and therefore is not realistic.  But, pessimists frequently make claim to being realistic.
> 
> But - real science now:  We only have one planet with life on it that we know about*.  That means no statistically relevant sample set, and thus no real understanding of the probabilities.  Statements as to what are "realistic expectations" are therefore hubris.  The only way to gain more information to decide the question either way, is to *look* for it.  And looking for it honestly requires a mind open to the possibility.  Deciding you already know the answer is the antithesis of scientific inquiry.
> 
> ...




And excessive optimism is no more realistic than is being overly pessimistic, but I would argue that saying there is no one else out there, because the odds are just too long, is the pessimism that we're talking about here. My mind is open to the possibility. In fact I consider it to be a high order of likelihood that other intelligent life exists out there, though that could also be seen as "hubris." I simply lean to the side that life is rare and special, rather than ubiquitous. 

Keep in mind, as I've been saying, that it's a matter of them looking for us as much as us looking for them.


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## Jhaelen (Jun 29, 2015)

Dannyalcatraz said:


> The trick is to figure out how those alien life forms THINK in different ways from us.  What are alien ethics?  Cultures?  Gets tricksy...



I like Stanislaw Lem's take on this. The recurring theme of his novels is that aliens are so utterly 'different' from us that there's practically no chance to ever communicate with them in a meaningful way. Take your pick (or better read them all!):
- Solaris, 
- Fiasco,
- Eden,
- His Master's Voice,
- The Invincible


----------



## Janx (Jun 29, 2015)

Morrus said:


> It's interesting how most scifi shows are very limited in their scope. Most are this galaxy, or a single galaxy.  Fewer span multiple galaxies.




You should know 400 billion from playing Eliteangerous.  That's about how many stars there are in the Milky Way (and thus how many stars they put in the game) 

Given the size of our galaxy, I usually find it a case of make-it-bigger-ism to go beyond the current galaxy.  The gap between them is so huge that it's improbable to reach if you haven't fully explored and conquered the current galaxy (which is also nigh-impossible to complete).


----------



## Morrus (Jun 29, 2015)

Janx said:


> You should know 400 billion from playing Eliteangerous.  That's about how many stars there are in the Milky Way (and thus how many stars they put in the game) .




I knew 400 billion many, many years before Elite: Dangerous ever existed.


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## Hand of Evil (Jun 29, 2015)

One of the problems I see is not is there intelligent life out there, is there intelligent life out there at the same time?  The window is very small.


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## Janx (Jun 29, 2015)

Hand of Evil said:


> One of the problems I see is not is there intelligent life out there, is there intelligent life out there at the same time?  The window is very small.




that and everybody is just so darn far away.  we and they aren't likely to come visiting any time soon.  If they make a radio, the signal takes forever to get here.  AND we have to be listening at the right time.

what if aliens existed on the opposite side of the galaxy and they setup a transmitter 200,000 years ago that ran for 90,000 years.  that means the transmissions passed us and stopped 10,000 years ago, long before we invented a radio to hear them.

We may not be alone in the galaxy, but for practical purposes, we are alone.


----------



## Morrus (Jun 29, 2015)

Or at least unless we discover that FTL communications are possible.


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## tomBitonti (Jun 29, 2015)

If intelligent life persists, then it should eventually be able to make Van Neumann probes and have them be nearly everywhere in the galaxy.  We might be only a century or so away from doing this ourselves.

Then, if intelligent life exists and is serious about contacting other life forms, it should be able to do so.  Whether the message was fixed would depend on whether the probes setup a message forwarding network.  The message would either be fixed, or would have a latest update on some forwarding interval.

I think you get back to the Fermi Paradox pretty quickly.  Perhaps limited to intelligent life similar to us in technology and that persists.

Aside, not sure if this has been covered: Here is a different equation kindof in the same area as the Drake quation:

http://io9.com/what-a-brand-new-equation-reveals-about-our-odds-of-fin-531575395

This wonderful story from Brin -- "Lungfish", C 1987 from "The River of Time" short story collection -- is a nice take on the problem:

http://www.astro.sunysb.edu/fwalter/AST389/TEXTS/lungfish1.txt

Thx!

TomB


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## Umbran (Jun 29, 2015)

tomBitonti said:


> If intelligent life persists, then it should eventually be able to make Van Neumann probes and have them be nearly everywhere in the galaxy.  We might be only a century or so away from doing this ourselves.




Not necessarily.  There is a major question as to whether technology will ever allow anyone (human or otherwise) to build devices that can last for the required centuries of exposure to interstellar space without maintenance.


----------



## Morrus (Jun 29, 2015)

tomBitonti said:


> If intelligent life persists, then it should eventually be able to make Van Neumann probes and have them be nearly everywhere in the galaxy.  We might be only a century or so away from doing this ourselves.




Yeah, but then it's millions of years to spread.  I think the estimate is 10 million years at 0.5c?  I may not be remembering correctly, though; it's been a while since I've read about that.



> I think you get back to the Fermi Paradox pretty quickly.




Yeah, that's basically what this thread is about.  We're all positing the standard solutions to the Fermi Paradox.


----------



## Bullgrit (Jun 29, 2015)

> Yeah, that's basically what this thread is about. We're all positing the standard solutions to the Fermi Paradox.
> 
> Read more: http://www.enworld.org/forum/showthread.php?462203-Alien-Intelligence/page4#ixzz3eSznpP6b



Actually, that may be what this thread has become, but it started out about whether human-like intelligence is an evolutionary freak, since it doesn't seem necessary for survival. I don't mind the turn this has taken, but we have discussed Fermi Paradox before.

Bullgrit


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## Morrus (Jun 29, 2015)

Bullgrit said:


> Actually, that may be what this thread has become, but it started out about whether human-like intelligence is an evolutionary freak, since it doesn't seem necessary for survival. I don't mind the turn this has taken, but we have discussed Fermi Paradox before.




The Fermi Paradox (even when it's not named as such in a thread) is such a compelling subject, I don't think I'll ever tire of talking about or reading about it and the questions it raises.  That's probably why most threads about alien life end up being about it.


----------



## Alzrius (Jun 29, 2015)

I've long been fond of Peter Watts' short story "The Things", which is a retelling of the 1982 John Carpenter film _The Thing_ from the point of view of the alien. It does an excellent job of putting us in a distinctly non-human mindset. And it has an audiobook version to boot!


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## Umbran (Jun 29, 2015)

Bullgrit said:


> Actually, that may be what this thread has become, but it started out about whether human-like intelligence is an evolutionary freak, since it doesn't seem necessary for survival.




Well, to be fair, *any* single trait is an evolutionary freak.  No single trait is *necessary* for survival.  Sight?  Nope - there are things that live without eyes?  Lungs?  Nope, there are things with only gills - heck, there are anaerobic things that don't need free oxygen, much less lungs!


----------



## tomBitonti (Jun 29, 2015)

Jhaelen said:


> I like Stanislaw Lem's take on this. The recurring theme of his novels is that aliens are so utterly 'different' from us that there's practically no chance to ever communicate with them in a meaningful way. Take your pick (or better read them all!):
> - Solaris,
> - Fiasco,
> - Eden,
> ...




Great stories!  (Although I didn't really care for His Master's Voice and didn't finish it.)  Lem's stories really provide a refreshing alternate view.

Nice to find another Lem fan out there.

Thx!

TomB


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## tomBitonti (Jun 29, 2015)

Umbran said:


> Not necessarily.  There is a major question as to whether technology will ever allow anyone (human or otherwise) to build devices that can last for the required centuries of exposure to interstellar space without maintenance.




Yeah, the inevitability of such devices is not proven.  In my defense, its a common science fiction conceit to presume that devices capable of crossing interstellar distances as functioning machines, including slowing down at a distant star, are possible.  But, we don't actually know that the crossing is possible engineering.  There might fundamental limitations, for example, information theoretic ones which give limits on error free communications.  I find oddly amusing the disconnect between popular views (e.g., the belief in aliens, or in the possibility of aliens) with what is known scientifically.  Interstellar crossings may be in the same space as 30' tall insects: Not physically possible.

To reply to a different post, I've read an estimate of around 3 million years for filling the galaxy with probes.  I'd say 10 million years is very reasonable as a comparable estimate.  But, that's still a short time compared with the several billions of years which seem to be the time frame to consider.

Thx!

TomB


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## Morrus (Jun 29, 2015)

tomBitonti said:


> Yeah, the inevitability of such devices is not proven.  In my defense, its a common science fiction conceit to presume that devices capable of crossing interstellar distances as functioning machines, including slowing down at a distant star, are possible.  But, we don't actually know that the crossing is possible engineering.  There might fundamental limitations, for example, information theoretic ones which give limits on error free communications.  I find oddly amusing the disconnect between popular views (e.g., the belief in aliens, or in the possibility of aliens) with what is known scientifically.  Interstellar crossings may be in the same space as 30' tall insects: Not physically possible.
> 
> To reply to a different post, I've read an estimate of around 3 million years for filling the galaxy with probes.  I'd say 10 million years is very reasonable as a comparable estimate.  But, that's still a short time compared with the several billions of years which seem to be the time frame to consider.
> 
> ...




My time frame is about another 50 years if I do well.


----------



## Umbran (Jun 29, 2015)

tomBitonti said:


> Interstellar crossings may be in the same space as 30' tall insects: Not physically possible.




Well, a 30 foot tall insect is not even *theoretically* possible, given the constraints of materials allowed to "insects", the structures insects us, and the like.

The space travel thing I would call more "not *practically* possible".  There's no single element that means it can't work, in theory, but just the cosmic ray bombardment kills the machine in practice, for example.


----------



## tomBitonti (Jun 29, 2015)

Umbran said:


> Well, a 30 foot tall insect is not even *theoretically* possible, given the constraints of materials allowed to "insects", the structures insects us, and the like.
> 
> The space travel thing I would call more "not *practically* possible".  There's no single element that means it can't work, in theory, but just the cosmic ray bombardment kills the machine in practice, for example.




Well, you could create an insect like creature (say, a very very large crab) which could work in the ocean which would not work on land.

It might be that a vessel attempting to cross even a very small (4 light year) interstellar distance might run into a similar physical limitation: It might be that no machine could cross the distance and remain functional, because of some limitation of physical materials.  I'm considering cosmic ray bombardment to be this sort of limitation.

Likewise, we don't really even know how long people can survive in low-G environments, beyond about a year or so: http://www.quora.com/What-is-the-lo...ore-it-is-too-hard-to-re-acclimatize-to-Earth

But we are getting pretty far from the original question.

Thx!

TomB


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## Umbran (Jun 29, 2015)

tomBitonti said:


> It might be that a vessel attempting to cross even a very small (4 light year) interstellar distance might run into a similar physical limitation: It might be that no machine could cross the distance and remain functional, because of some limitation of physical materials.  I'm considering cosmic ray bombardment to be this sort of limitation.




Semantic quibbling.  I agree that we may be limited by materials (and even more, by energy sources).  I just wouldn't call it a failure in theory, but only in practice.


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## tomBitonti (Jun 30, 2015)

So ... here's a question ... to try to tie this back a bit: Is there a way for a species to cross interstellar space without evolving intelligence?

I suppose space borne spores thrown up by meteorite impacts is a possibility (maybe a very slight one).  But anything else?

Thx!

TomB


----------



## Bullgrit (Jun 30, 2015)

> So ... here's a question ... to try to tie this back a bit: Is there a way for a species to cross interstellar space without evolving intelligence?
> 
> I suppose space borne spores thrown up by meteorite impacts is a possibility (maybe a very slight one).
> 
> Read more: http://www.enworld.org/forum/showthread.php?462203-Alien-Intelligence/page5#ixzz3eUoEHZYW



Isn't that one theory on how life started (came to) on Earth?

Bullgrit


----------



## Dannyalcatraz (Jun 30, 2015)

Supposedly, Life came to earth via impact with the comet, Milton Bradley.


----------



## tomBitonti (Jun 30, 2015)

Bullgrit said:


> Isn't that one theory on how life started (came to) on Earth?
> 
> Bullgrit




I believe that it is, but I don't know if there is any evidence to suggest that it is plausible.

I'm thinking there have been lots of experiments which gathered particles from outer space, which provides *some* negative evidence.

Thx!

TomB


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## Mustrum_Ridcully (Jun 30, 2015)

MechaPilot said:


> If there are other intelligent life forms (as in having at least human-level intelligence) in our galaxy, we probably won't meet them.  If they truly are intelligent, they will cross the galactic street the moment they see us coming.



Yeah yeah, the old spiel about how we are not really all that smart and aliens would avoid us.

As if there is any reason to believe that alien intelligence wouldn't go through the exact same problems as we did, would be just as short-sighted or narrow-minded as we were.

Evolution is not a process that creates perfect things. It creates surviving things.  
That can mean nasty things - like the willingness to kill others for their resources. The ones that didn't kill for the resources when they weren't smart enough to find an alternative? They died out.
At least we are aware of our imperfections. It might not be enough in the end, but it might also be. 

There can still be other reasons to avoid us, of course. Heck, any form of non-organic intelligent life might be different that we would have trouble communicating with each other or recognizing each other. They might not want to interfere with us. They might simply have decided that trying to contact other life is pointless, as the chances of finding any is too slim, and focus on themselves and their star system.
And of course, the more likely thing is they aren't actively avoiding us - they are just too far away.



Morrus said:


> The inverse square law is the issue. Transmissions  degrade over distance very rapidly.  Given that ours aren't exactly  strong to begin with, you'd have to be looking pretty darn hard with  extremely sensitive detection equipment even just at a light year  out.




Indeed.
IIRC, something like 95 % of the signals send to the Voyager Probe are used just for error handling. And that's where we really make an active effort to send a strong transmission at logn distance. 

And Voyager is only about 0.2 % of a light year away.


----------



## Mustrum_Ridcully (Jun 30, 2015)

tomBitonti said:


> So ... here's a question ... to try to tie this back a bit: Is there a way for a species to cross interstellar space without evolving intelligence?
> 
> I suppose space borne spores thrown up by meteorite impacts is a possibility (maybe a very slight one).  But anything else?
> 
> ...




Depends on how wide you want to cast the net, doesn't it? 

During galaxy collisions, suns can basically knocked out of the respective galaxies and fly much faster than the rest of the stars nearby - if the whole system is kept intact, it could include a planet with life, and thus we'd have non-intelligent life crossing interestellar space.

But would that satisfy you? I think any lifeform to survive a long, interstellar travel would need to be very resilient or well contained, or need to have an ecosphere that can last sufficiently long - basically, if the cosmic rays kill your life after a while, it must be able to regenerate itself in some form.


----------



## Jhaelen (Jun 30, 2015)

Umbran said:


> Well, a 30 foot tall insect is not even *theoretically* possible, given the constraints of materials allowed to "insects", the structures insects us, and the like.



Hmm. How large could an insect possibly be? I seem to recall there once was a type of giant insect (Meganeura...) that had a wing span of about 3 feet. How close was Meganeura to the theoretical maximum?

Could there be larger insects if we fiddle with other parameters like gravity or atmospheric composition?


----------



## Ryujin (Jun 30, 2015)

Jhaelen said:


> Hmm. How large could an insect possibly be? I seem to recall there once was a type of giant insect (Meganeura...) that had a wing span of about 3 feet. How close was Meganeura to the theoretical maximum?
> 
> Could there be larger insects if we fiddle with other parameters like gravity or atmospheric composition?




I suppose that depends upon whether you would consider an insect that evolved to include an endoskeleton to still be an insect.


----------



## Umbran (Jun 30, 2015)

Jhaelen said:


> Hmm. How large could an insect possibly be? I seem to recall there once was a type of giant insect (Meganeura...) that had a wing span of about 3 feet.
> 
> How close was Meganeura to the theoretical maximum?




Many folks seem to think the maximum size is limited by strength/weight of materials of the exoskeleton.  My understanding is that oxygen transfer is the more limiting factor - arthropods don't have lungs, and there are limits to how much oxygen they can get into their systems.

Meganeura lived at a time with higher O2 concentration in the atmosphere, and it is suggested that this allowed larger insects and other arthropods.  A bug that size wouldn't make it today.



> Could there be larger insects if we fiddle with other parameters like gravity or atmospheric composition?




Yes.


----------



## Umbran (Jun 30, 2015)

tomBitonti said:


> So ... here's a question ... to try to tie this back a bit: Is there a way for a species to cross interstellar space without evolving intelligence?
> 
> I suppose space borne spores thrown up by meteorite impacts is a possibility (maybe a very slight one).  But anything else?




Hm.  Usually, we assume that life must evolve on a planetary body, because that's the only place where we have matter dense enough, and enough warmth.  The basic problem is getting it out of the gravity of the planet after that.  Even if you could imagine a system evolving to launch something into space, the energy required to leave a planet is very large.  The energy required to leave a solar system is even larger.  What you ask is difficult.

But then I am reminded of Gregory Benford's book, "Heart of the Comet", in which researchers land on a comet, and find life.  Not *intelligent* life, but something more like fungus.  The heat of their station throws the growth patterns of this deep-space-cold adapted life into far overdrive, and wackiness ensues.

If you can get life out into the Oort cloud of the star, then maybe some random gravitational interactions with a passing star might break a thing loose and wandering.


----------



## Dannyalcatraz (Jun 30, 2015)

Something like a tardigrade might be able to hop planets under extremely long odds, too.


----------



## Umbran (Jun 30, 2015)

Dannyalcatraz said:


> Something like a tardigrade might be able to hop planets under extremely long odds, too.




Yeah, but hopping planets is not hopping stars.


----------



## Dannyalcatraz (Jun 30, 2015)

Clearly not, but if there is a terrestrial critter that shows how it could be done, it would be the tardigrade.  Tough little bastards.


----------



## Cleon (Jun 30, 2015)

Umbran said:


> Many folks seem to think the maximum size is limited by strength/weight of materials of the exoskeleton.  My understanding is that oxygen transfer is the more limiting factor - arthropods don't have lungs, and there are limits to how much oxygen they can get into their systems.




That's not quite true. While none have lungs that work like vertebrates do, many chelicerates have "book lungs" and some crabs have "branchiostegal lungs". They tend not to be as good as vertebrate lungs though, being generally less efficient and more prone to water-loss.

Furthermore, if the arthropod gets its oxygen from water rather than air that hardly matters, since it'll use gills to breathe - and arthropods can grow to impressive sizes in water. I believe the current record is about 10 feet long for an extinct Eurypterid.

However, I don't see why the above matters that much. The aforementioned "30-foot alien insect" would only _resemble_ an insect. There's no reason its circulatory and skeletal anatomy would include the limitations that prevent terrestrial arthropods reaching dinosaur size.


----------



## MechaPilot (Jun 30, 2015)

Mustrum_Ridcully said:


> Yeah yeah, the old spiel about how we are not really all that smart and aliens would avoid us.




You have me wrong.  I'm not saying intelligent aliens would avoid us because we're not smart.  It's just, as a species, we are currently horrible people despite the fact that we are smart enough to know better.  We have the intelligence to be better people, we just don't have the motivation.  Maybe that will change, or maybe some other life form will find the radioactive ruin of our civilization.


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## tomBitonti (Jun 30, 2015)

Cleon said:


> However, I don't see why the above matters that much. The aforementioned "30-foot alien insect" would only _resemble_ an insect. There's no reason its circulatory and skeletal anatomy would include the limitations that prevent terrestrial arthropods reaching dinosaur size.




But, that sidesteps the point: A creature which has the common physical structure of an insect can't survive as a land dwelling terrestrial organism if enlarged to be 30' tall.  Basic physics and limits on material properties prevent it.

The question is whether there are materials with the necessary physical properties to endure a journey to a nearby star, including deceleration, and remain functional.

One could ask a similar question as a sociology question: Could a generation ship actually keep a functioning and healthy society, for thousands of years?

I don't think we have an answer to either question.

Thx!

TomB


----------



## Umbran (Jun 30, 2015)

Bullgrit said:


> Isn't that one theory on how life started (came to) on Earth?




I wanted to go back to this for a moment...

To answer the question:  Yes, and it is possible that life got here that way, but....

...that theory doesn't answer any hard questions, and adds several.  You still need life starting from scratch *somewhere*.  I don't see how starting somewhere else and travelling across interstellar distances is somehow more likely than just starting here. 

As usual, passing the buck doesn't generally solve anything


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## Dannyalcatraz (Jul 1, 2015)

tomBitonti said:


> But, that sidesteps the point: A creature which has the common physical structure of an insect can't survive as a land dwelling terrestrial organism if enlarged to be 30' tall.  Basic physics and limits on material properties prevent it.



What I think his point was: just because it looks like a bug, doesn't mean it is made like a bug.  It could have an exoskeleton made of something much lighter and stronger than chitin, for instance.  Its musculature could be stronger per pound.  Instead of oxygen, it may "breathe" something more plentiful in our atmosphere.


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## Umbran (Jul 1, 2015)

Dannyalcatraz said:


> What I think his point was: just because it looks like a bug, doesn't mean it is made like a bug.




In the thing I was responding to, it wasn't a 30' tall thing that *looks* like a bug.  It was a 30' tall insect.  As in, made like a bug, built on the terrestrial insect plan:  Chitin for exoskeleton, no endoskeleton, insectoid breathing apparatus, and so on.  Tom and I were agreeing that such wasn't possible, and quibbling over what counted as "theoretically" impossible vs "practically" impossible.

Can we imagine a thing that looks an awful lot like an insect,t hat is 30' tall?  Sure.  But that wasn't the point of the discussion at that time.


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## Dannyalcatraz (Jul 1, 2015)

Except Cleon was clear when he posited the initial example: the alien would resemble a bug, but would actually have a different structure in reality.

You and Tom are arguing against something not put forth.  A straw...bug.

Edit: apologies- Cleon didn't posit the original example.  No strawbug fallacy exists.


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## Mustrum_Ridcully (Jul 1, 2015)

MechaPilot said:


> You have me wrong.  I'm not saying intelligent aliens would avoid us because we're not smart.  It's just, as a species, we are currently horrible people despite the fact that we are smart enough to know better.  We have the intelligence to be better people, we just don't have the motivation.  Maybe that will change, or maybe some other life form will find the radioactive ruin of our civilization.



There are horrible people, but there are also people that are decidedly not horrible, and you're selling them short, and basically implicitely demotivitating people that try to do good. 
It's doubtful that any alien intelligence was "nice" from the start. At best, any terms of niceness might be meaningless for it, say for an intelligence like in Solaris.


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## Dannyalcatraz (Jul 1, 2015)

Mustrum_Ridcully said:


> It's doubtful that any alien intelligence was "nice" from the start.




"And they haven't gotten any nicer since then.  They're all a bunch of..."


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## Umbran (Jul 1, 2015)

Dannyalcatraz said:


> "And they haven't gotten any nicer since then.  They're all a bunch of..."




Psst!  That's one right there!  On his head!  Isn't it obvious that hair isn't from this planet?


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## Dannyalcatraz (Jul 1, 2015)

It would explain a bunch or things...


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## Ryujin (Jul 1, 2015)

Umbran said:


> Psst!  That's one right there!  On his head!  Isn't it obvious that hair isn't from this planet?




Clearly a Saurian in disguise, likely descended from some alien dino like Dimetrodon.


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## Cleon (Jul 1, 2015)

tomBitonti said:


> But, that sidesteps the point: A creature which has the common physical structure of an insect can't survive as a land dwelling terrestrial organism if enlarged to be 30' tall.  Basic physics and limits on material properties prevent it.




I don't remember anyone specifying it had to be a land dwelling terrestrial organism, it'd be a lot easier if it was floating in water or freefall.

Anyhow, I fear we're talking at cross-purposes here. We need to agree on what we mean by 30-foot insect.

If it's _literally_ an insect in a taxonomic sense (i.e. a member of the class Hexapoda, or rather Insecta), its evolutionary ancestors would have to originate on Earth and then somehow get transplanted to an extraterrestrial environment were they become the aforementioned ten yard arthropod. Maybe a bunch of ants hitch-hiked a ride on a UFO.

You seem to be talking about a class of alien lifeform that just happened to evolve identical biology to earth insects - chitinous exoskeletons, six legs, division into head-thorax-abdomen, tracheal respiration, and so on and so forth.

In both the former cases, I hope we can all agree that growing one to 30 feet is, ah, _problematic_. Insect anatomy is just not compatible with sizes longer than a few inches. I suppose it's theoretically possible if it's an entirely aquatic insect with very, very elongated body. If it's 30 feet long and half an inch wide, at least its trachea would still be able to diffuse oxygen through its tissues. It'd probably be unable to intake enough food through its comparatively tiny mouth, so it'd likely have to feed through its skin - some kind of symbiotic photosynthetic or chemosynthetic bacteria would be a likely solution. It'd be extremely fragile and unsuited for life anywhere with violent weather, let alone predators.

However, while such a hypothetical creature may be a "30 foot insect" in a technical sense, it'd look more like a giant Polychaete worm. I'm visualizing a _Lamellibrachia luymesi_ with a half-dozen legs at one end.

Then, to make the poor thing's physiology even more implausible, we're talking about making it intelligent. Some kind of communal mind, perhaps, with a lot of these insect-worms networked together. Or maybe they have information-processing symbiotes under their chitin as well as food-producing ones, which allow them to reach sapiency.

If we want a 30 foot intelligent alien that, say, looks like a praying mantis as big as a house, I don't see any way it can be an actual "insect" in any real sense. It just looks like one, but its physiology would have to work in very un-insect like ways for it to be viable.


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## tomBitonti (Jul 1, 2015)

Cleon said:


> I don't remember anyone specifying it had to be a land dwelling terrestrial organism, it'd be a lot easier if it was floating in water or freefall.
> 
> Anyhow, I fear we're talking at cross-purposes here. We need to agree on what we mean by 30-foot insect.
> If we want a 30 foot intelligent alien that, say, looks like a praying mantis as big as a house, I don't see any way it can be an actual "insect" in any real sense. It just looks like one, but its physiology would have to work in very un-insect like ways for it to be viable.




Hi,

Yeah.  To clarify.  I'm not really interested in the properties of 30' insects, other than as an example.  And I'm not talking about 30' alien insects.  The idea is of an insect, say, a praying mantis, enlarged with minimal alterations other than size.

That's absurd, of course, a 30' praying mantis would collapse on itself, or would suffocate, or would fail to transport heat away, &etc.

But, television has had no problem depicting a 30' praying mantis despite the absurdity.

Similarly, science fiction authors (mostly) have no trouble postulating interstellar voyages using more-or-less known physics.  And little trouble postulating multi-generation ships.  Most, but not all: A few have approached the problem with a more realistic bent, or have focused the story one of the engineering problems.

Now, an interstellar crossing sounds possible.  But, when you look at the engineering details, is it actually possible, working within known materials and our known understanding of physical processes?  

My assertion is that we don't actually know.  An interstellar crossing might fall to any number of physical limitations, in a similar fashion that a 30' praying mantis collapses on itself.

I think the flaw is similar; we've just changed a different dimension of the problem.

Thx!

TomB


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## Umbran (Jul 1, 2015)

tomBitonti said:


> Now, an interstellar crossing sounds possible.  But, when you look at the engineering details, is it actually possible, working within known materials and our known understanding of physical processes?
> 
> My assertion is that we don't actually know.  An interstellar crossing might fall to any number of physical limitations, in a similar fashion that a 30' praying mantis collapses on itself.
> 
> I think the flaw is similar; we've just changed a different dimension of the problem.




I think we need to look at two different scenarios:

We started this line of discussion considering unmanned, robotic probes.  Barring technology we don't know is possible, an interstellar crossing for it would mean centuries running without maintenance.  That's a problem.

A generation ship, with capacity to recycle, and people to make new parts and even entire new systems?  It still takes centuries, but is a much different question.


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## tomBitonti (Jul 1, 2015)

Umbran said:


> I think we need to look at two different scenarios:
> 
> We started this line of discussion considering unmanned, robotic probes.  Barring technology we don't know is possible, an interstellar crossing for it would mean centuries running without maintenance.  That's a problem.
> 
> A generation ship, with capacity to recycle, and people to make new parts and even entire new systems?  It still takes centuries, but is a much different question.




Yeah, whole different domains.  I put in both domains because they track the two most common scenarios: Sending a small(ish) robotic probe at relatively high speeds, and sending a large multi-generational ship, at much lower speeds.  I think the end result is the same for either: We don't know if the problems in either domain are solvable.  But very different problems.

My assertion is a stronger take on the "don't know if the problems are solvable" statement.  That is, I assert that the problems might not be solvable due to fundamental physical limitations.  That is the difference between saying "we haven't found a material which would work" and "we haven't found a material which would work, and the underlying science predicts that no workable material is possible".  Otherwise, the comparison to the absurd 30' praying mantis doesn't work.

Or, in a slightly different form: Not only do we not know if interstellar travel is possible.  We don't even know if the idea of interstellar travel is less absurd than the idea of a 30' praying mantis.

Thx!

TomB


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## Cleon (Jul 1, 2015)

Umbran said:


> I think we need to look at two different scenarios:
> 
> We started this line of discussion considering unmanned, robotic probes.  Barring technology we don't know is possible, an interstellar crossing for it would mean centuries running without maintenance.  That's a problem.




I'd assume said probe would be maintaining itself.

The thread was talking Von Neumann-type machines, if I recall.

Since such a machine contains instructions and equipment capable of replicating itself, presumably it won't require that much more work to give it the capability to replicate and replace damaged parts of itself. The simplest approach would likely to have the probe consist of multiple identical Von Neumann machines, and if one of them breaks down the others take it apart and rebuild it. You'd certainly need a decent degree of built-in redundancy so there's enough "working" parts to recognize and correct the "damaged" parts.

That probably falls into "technology we don't know how to do", but the same could be said for insterstellar generation ships.



Umbran said:


> A generation ship, with capacity to recycle, and people to make new parts and even entire new systems? It still takes centuries, but is a much different question.




Hmm...

The question is, what difference does it make if this interstellar vessel relies on a bunch of organic lifeforms or Von Neumann robots for its self-reproducing repair crew?

Arguably, assuming the latter is technically possibly, it's probable a lot better. Robots can be engineered without many of the properties that make living creatures less optimal for space travel.

If for some reason a living crew is just as efficient as a robot one, the problem of "cultural drift" may be a lot worse with the organics. The expedition would be pointless if the crew's society has changed so much it has no inclination to disembark at the generation ship's destination.


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## Umbran (Jul 1, 2015)

Cleon said:


> The thread was talking Von Neumann-type machines, if I recall.
> 
> Since such a machine contains instructions and equipment capable of replicating itself, presumably it won't require that much more work to give it the capability to replicate and replace damaged parts of itself.




Maybe.  Consider that humans are constructed to replicate themselves.  But our ability to repair ourselves is rather limited.  Being able to replicate does not imply the ability to completely self-repair.  Being built to mine asteroids and manufacture a new probe doesn't imply the ability to disassemble one's self and replace parts.  



> The question is, what difference does it make if this interstellar vessel relies on a bunch of organic lifeforms or Von Neumann robots for its self-reproducing repair crew?




Well, the crew comes with a bunch of self-repair that you don't have to do any design work to get, and medical capabilities to cover much of the rest.   More important to Tom's point, the crew can come up with entirely new solutions to problems in-flight.

In effect, building a von Neumann probe to do all this requires reinventing many wheels already developed for humans - mostly in terms of intelligence and adaptability.  Right now, we find exploration to be more efficient with probes, but those probes do *not* have all the abilities of a human laboratory.  They are far cheaper than sending humans specifically due to their limited capacities.  When you may actually need the full capabilities of lab and factory, the probe may not be the most efficient route.  Machines are great for specialized tasks, but maybe not for generalized goals.


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## Cleon (Jul 1, 2015)

Umbran said:


> Maybe.  Consider that humans are constructed to replicate themselves.  But our ability to repair ourselves is rather limited.  Being able to replicate does not imply the ability to completely self-repair.  Being built to mine asteroids and manufacture a new probe doesn't imply the ability to disassemble one's self and replace parts.




Well not so much constructed to replicate themselves as randomly evolved to produce offspring. Many of the limitations on human self-repair ability are down to accidents of ontogeny which are pretty irrelevant to a robot probe. It's easy to imagine a modular machine that can easily replace a defective limb or brain by simply plugging in a new one. That's a lot harder to do with a lifeform!

Oh, and I was talking about a probe with a bunch of Von Neumann machines in it. If each can make replacement parts or entire new machines from materials mined from an asteroid, it ought to be able to do the same from the materials of one of its companions that's broken down. Presumably there'll be some wastage and energy loss involved in the process, but it would hopefully extend the probe's useful lifespan far beyond a machine incapable of self-repair. The probe could carry spare fabrication material of course, but it'd be logistically simpler to have it pre-formed into useful components like parts of the Von Neumann machines, so you might as well put those parts together into functional machines in case the probe needs their processing abilities.



Umbran said:


> Well, the crew comes with a bunch of self-repair that you don't have to do any design work to get, and medical capabilities to cover much of the rest.   More important to Tom's point, the crew can come up with entirely new solutions to problems in-flight.
> 
> In effect, building a von Neumann probe to do all this requires reinventing many wheels already developed for humans - mostly in terms of intelligence and adaptability.  Right now, we find exploration to be more efficient with probes, but those probes do *not* have all the abilities of a human laboratory.  They are far cheaper than sending humans specifically due to their limited capacities.  When you may actually need the full capabilities of lab and factory, the probe may not be the most efficient route.  Machines are great for specialized tasks, but maybe not for generalized goals.




The "If for some reason a living crew is just as efficient as a robot one" includes the assumption that the robots have some kind of AI or expert system that perform roughly par to humans, at least as far as whatever task the interstellar vessel's designers sent it out to the stars to perform.

The details of said performance may be very different, of course. The human crew might solve problems with the ingenuity of their soggy brains which the robots avoid by meticulous error-checking or by computer modelling myriads of responses to an approaching threat to try to guess which is more likely to succeed.

Or, the ship can use a combination of the two. A generation ship full of humans might have self-repairing systems that require minimum maintenance. A crew of robots might fly an interstellar colony ship through space for centuries, then defrost the human crew to do the tricky work of figuring out surprises and supervise the womb-banks to produce the colony's "first generation".

Since we don't know the technical feasibility or difficulty of either approach, it seems premature to assume which one is more difficult. A human generation ship would have to be enormous compared to a robot probe. If it uses up the resources to build a thousand robot probes but is only ten times more likely to produce the results you want, there'd be little point sending one. Contrariwise, if the ship's task is something only humans can do (abstract thinking beyond the future robot's AI, breeding little humans, or whatever), you'd have to send the generation ship.


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## Mustrum_Ridcully (Jul 3, 2015)

Cleon said:


> Well not so much constructed to replicate themselves as randomly evolved to produce offspring. Many of the limitations on human self-repair ability are down to accidents of ontogeny which are pretty irrelevant to a robot probe. It's easy to imagine a modular machine that can easily replace a defective limb or brain by simply plugging in a new one. That's a lot harder to do with a lifeform!



It may look simple at first, until you start to realize that your machine might need to be quite complex to be able to do all the kind of operations it needs to be capable of.
There is no real point in sending out a Von Neumann machine that is as smart as a tardigrade... That wouldn't really serve any exploration goals.

So in the end you need a machine that cannot just repair or construct itself, but also have the ability to gather all it needs from the environment. And still have all the capabilities to "explore" the world and learn stuff. 

You may end up with a machine that is just as complex as a human body. Maybe it's better suited to exist in space, at least, that might make it superior to generation ship exploration. But maybe it doesn't really matter anymore at that point, because it's extremely difficult to create somethnig s complex that can live in any type of environment, and your machine might need to operate in different environment to retrieve the materials it needs.


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## Cleon (Jul 3, 2015)

Mustrum_Ridcully said:


> It may look simple at first, until you start to realize that your machine might need to be quite complex to be able to do all the kind of operations it needs to be capable of.
> There is no real point in sending out a Von Neumann machine that is as smart as a tardigrade... That wouldn't really serve any exploration goals.
> 
> So in the end you need a machine that cannot just repair or construct itself, but also have the ability to gather all it needs from the environment. And still have all the capabilities to "explore" the world and learn stuff.
> ...




I'm not foolish enough to think we're hypothesizing about something that's easy to do. 

If the probes are just sent out to see what's out there, maybe you would only need something as smart as an arthropod, since it's mission function is to look about itself and beam what it sees back home. I wonder how a tardigrade's information-processing capacity compares to a Voyager space probe?

As for the complexity question, I don't see why it would be engineered to live in any environment in space. How could it be? There are some very hostile places out there, and building a machine to cope with all of them would be impossible. Indeed, a lot of places in space are so harsh the probe would have to view them from a very long distance to avoid destruction. It's far more likely that such a probe would be designed to self-reproduce in relative "comfortable" areas of space, by mining asteroids and the like. It might drop spare copies of itself or separately built sensor packs into more hostile areas in suicidal scouting runs while keeping enough probes back where its safe to continue the mission.

Oh, and regarding the "just as complex as a human body". It's worth bearing in mind that a lot of that complexity is unnecessary from an engineering standpoint. The design of living organisms has been kludged together by evolution, so there's a lot that is needlessly complicated* and a few parts that are pretty useless (but not so useless they're harmful to survival). A robot wouldn't be designed with vestigial organs that are left-overs from when it was a fish but don't do anything now, or have molecular "machinery" that's much larger than it needs to be.

*That's assuming it actually is needlessly complicated, presumably some of that complexity is useful but we just haven't figured out what it's good for. At a minimum, the complexity of having lots of spare "parts" give the lifeform more directions it can evolve in. I'm not sure you'd really want your robot probe to do much evolving, or rather than scouting the galaxy you might find you've inadvertently seeded it with a mechanical civilization.


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## Umbran (Jul 3, 2015)

Mustrum_Ridcully said:


> You may end up with a machine that is just as complex as a human body. Maybe it's better suited to exist in space, at least, that might make it superior to generation ship exploration.




Or maybe not.  One of the problems with complexity is that it tends to be fragile.  By the time you've built a machine that can do all the required things, it may no longer be robust.

And, you also then hit upon the efficiency question.  If you add all this R&D effort to build such a thing together, is it really any cheaper and easier than sending a human?


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## Mustrum_Ridcully (Jul 6, 2015)

Cleon said:


> Oh, and regarding the "just as complex as a human body". It's worth bearing in mind that a lot of that complexity is unnecessary from an engineering standpoint. The design of living organisms has been kludged together by evolution, so there's a lot that is needlessly complicated* and a few parts that are pretty useless (but not so useless they're harmful to survival). A robot wouldn't be designed with vestigial organs that are left-overs from when it was a fish but don't do anything now, or have molecular "machinery" that's much larger than it needs to be.



Well... A perfectly designed robot might not... But if it's a human-made project with a budget and all, it might use several standard components that have features not actually needed for that robot. 

Say, an operating system that stil has compatbility features for software that was designed for older versions... Software that will of course never run on the robot. 
A signal processor that also has a build-in encryption module so it can stream 40K-3D-Smellovision Signals with all copyrights intact... 
Or just a telescopic arm with a fancy adaptive-attachment system so it can be installed on multiple different industry robots, even if this robot needs only one particular type of attachment.


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## tomBitonti (Jul 6, 2015)

Let's posit that sending a human doesn't make sense, but that sending an unsophisticated robot doesn't make sense either.

A human is impractical for space travel, and doesn't handle the very long time frames very well.

An unsophisticated robot, in either it mechanicals or its software, would be insufficient to the task of long term autonomous operation.

My conclusion is that if a interstellar voyage were taken, it would require a hybrid of capabilities of people and robots.

My question then is whether this is possible, either as a simple material question: Can we make machines, even ones which self repair, which can last a journey of hundreds to thousands of years; Or as a information processing question: Can we make a thinking device which will have both sufficient thought power to be adequate to the journey, and which would remain functional (== sane) for the duration.

I think that the question of whether a generational ship would be able to maintain a stable society is a good question to ask, in that it might highlight problems of maintaining high intelligence over time.

Thx!

TomB


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## Umbran (Jul 6, 2015)

tomBitonti said:


> Let's posit that sending a human doesn't make sense, but that sending an unsophisticated robot doesn't make sense either.
> 
> A human is impractical for space travel, and doesn't handle the very long time frames very well.




I'd like to take this in a different direction.

If humans *cannot* go to these places, why bother spending the resources to develop, build, and launch such a sophisticated machine?   

Scientific exploration for the sake of exploration is actually based on the idea that you can never tell what piece of information will be useful.  However, if we are admitting that humans are forever trapped in this one solar system, we are also admitting that much of the information gained will be moot, as we won't ever be interacting with any system other than our own.  We might be as well or better off just using what remote data-gathering systems we can (telescopes, and such), and otherwise saving the resources to directly understand the system we have and have a chance of interacting with.


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## Janx (Jul 6, 2015)

Umbran said:


> I'd like to take this in a different direction.
> 
> If humans *cannot* go to these places, why bother spending the resources to develop, build, and launch such a sophisticated machine?
> 
> Scientific exploration for the sake of exploration is actually based on the idea that you can never tell what piece of information will be useful.  However, if we are admitting that humans are forever trapped in this one solar system, we are also admitting that much of the information gained will be moot, as we won't ever be interacting with any system other than our own.  We might be as well or better off just using what remote data-gathering systems we can (telescopes, and such), and otherwise saving the resources to directly understand the system we have and have a chance of interacting with.




I dunno, because we can?  

Because by trying to do so, we may find a means to do so.  But if we accept our fate and don't try, then we as a species are doomed.  

Eventually the 26 million year die off will happen, the sun will die, asteroids, ice age, whatever.

Wouldn't it be nice to know that we'll get there someday?

Otherwise, what's the point of all that science.  We might as well just go back to being hunter gatherers.


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## tomBitonti (Jul 6, 2015)

Umbran said:


> I'd like to take this in a different direction.
> 
> If humans *cannot* go to these places, why bother spending the resources to develop, build, and launch such a sophisticated machine?




Humans may be unsuitable for the crossing, but maybe can be created on the far side.  _If_ we can send an artificial womb, and _if_ we can send data across that much time and space, and _if_ a human raised by hybrid intelligence could acquire our accumulated knowledge, then the journey could still be worthwhile.

If sophisticated machines could be sent, they might be able to send back information, and that might make the journey worthwhile.

We might also eventually create capable cyborgs which would be adequate to the crossing, and while the crossing might not be worth our doing, it might be worth theirs.

Thx!

TomB


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## Umbran (Jul 7, 2015)

tomBitonti said:


> Humans may be unsuitable for the crossing, but maybe can be created on the far side.




I think this still qualifies as humans making the crossing.  You have humans at either end, so unless they teleported, they must have crossed the intervening space. 

Same goes for cyborgs.  



> If sophisticated machines could be sent, they might be able to send back information, and that might make the journey worthwhile.




This is the one that I question.  We are talking efforts to create a machine that are, quite frankly, akin to reaching the technological singularity.  The cost would be... astronomical (pun intended).  The time to get payoff on that investment would be long compared to the lifetimes of nations.  The information would have to be ... stellar in order to make the expenditure worthwhile, especially given that much of the information would turn up to be academic, without any practical application for humans.

And I'm saying this as a person who *loves* science.


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## Umbran (Jul 7, 2015)

Janx said:


> Wouldn't it be nice to know that we'll get there someday?




I, personally, take no comfort in such a Pyrrhic achievement.  "We slung a machine here, but died out anyway," isn't much of an epitaph. 



> Otherwise, what's the point of all that science.  We might as well just go back to being hunter gatherers.




As I noted, the point of "all that science" is that we don't generally know which bits of it will turn out useful.  I am positing a scenario when we have better knowledge of what is or isn't useful.

But, you do raise a good point.  There have been those who have questioned - if we cannot make it to the stars, if the Universe really is too hostile for us to spread at least through our own galaxy, maybe giving it all up and becoming hunter-gatherers isn't such a bad idea.


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## Mustrum_Ridcully (Jul 10, 2015)

Umbran said:


> I'd like to take this in a different direction.
> 
> If humans *cannot* go to these places, why bother spending the resources to develop, build, and launch such a sophisticated machine?
> 
> Scientific exploration for the sake of exploration is actually based on the idea that you can never tell what piece of information will be useful.  However, if we are admitting that humans are forever trapped in this one solar system, we are also admitting that much of the information gained will be moot, as we won't ever be interacting with any system other than our own.  We might be as well or better off just using what remote data-gathering systems we can (telescopes, and such), and otherwise saving the resources to directly understand the system we have and have a chance of interacting with.




I don't think we will ever be in a position where we can categorally say that we will not get any information that will be useful to us. Maybe we need some robots to look more closely at a particular stellar object, say a black hole, to solve a theoretical question on which we can base another project that will help humanity. Say, if the data supports theory A, we can start working on a giant, century long project that will cost us most of the resources we can acccess, but when done, we reach a significant milestone. But if we're wrong, doing the project would mean our predictable demise because we just blew all our resources.


One of the "fun" aspects of a generation ship that has to work for centuries or millennia is that we aren't even sure that the "generation ship" we're on will work that long for us. Will our society break down? Will we ruin the ecosphere beyond the ability to sustain _us_?


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