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When Are the Intelligent Aliens?

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Re: When Are the Intelligent Aliens?

#31

Post by ChuckMcM »

exratione wrote: post #11

Obligatory talking points associated with the Fermi Paradox: - It takes a very short time in comparison to the age of the galaxy for a single self-replicating probe to result in a descendant probe visit to every star. A few million years. This means that you cannot really argue plausibly that all civilizations fail to do this - it would take trivial effort for just one faction within just one advanced civilization to…

This is a good summary. One of the missing pieces is we don't know what the minimum set of combinational factors are to create "advanced" civilization.

The scare quotes for advanced here are that two incompatible definitions for civilization quality compete for the nominative "advanced." In the current context advanced means we've developed machines that carry us into space, we can create habitats to survive in even when our surrounding habitat is inhospitable and we leverage natural resources to create excess food. An alternative context for "advanced" is that your civilization exists in balance with the other processes on the planet, you don't create anything that that wouldn't be created by natural processes inherent in the system, and your resource utilization is at a rate that does not exceed its replenishment rate. Further you explicitly do not use any resource that is not naturally replenished.

In the context of that dichotomy, the question might be "Why didn't the Dinosaurs develop space flight?" They lived on the planet for millions of years before we got here, there is evidence that their cognitive capacity was at least as large as ours, and some species had the ability to manipulate matter at least as well as our paleolithic ancestors did. So why didn't they build giant Dinosaur cities, grow Dinosaur food, and build institutions of higher learning? Depending on your timeline we went from struggling ape to SpaceX in 3 - 5 million years. They had 165 million years to figure it out. Why were they even on the planet when the asteroid hit, and/or why didn't they do something about it before it hit? Using Dinosaur lasers or something.

Depending on how you count we've gone through 5 to 7 nearly total extinctions on this planet. What made this last one special? What is the key set of things that have to be true in order for life to go from being intelligent to manipulating everything around it in its environment to serve the will of that intelligence?

They are complex questions. Great fun to contemplate on camping trips, while under the influence, and when you've run out of other 'safe' conversational starters.

Re: When Are the Intelligent Aliens?

#32

Post by joe_the_user »

sampo wrote: post #19
Udo wrote: post #17

Earlier quoted context omitted.

Considering the vast time scales and the vastness of the galaxy, the most plausible explanation for me is still that we happen to live in a historical dark zone. But it's fun to speculate since any number or combination of events might be responsible for the absence of fellow civilizations. There is a Great Filter argument that tries to say that we're really, really, really special or that our civilization-ending eve…

> the most plausible explanation for me is still that we happen to live in a historical dark zone. I am no expert, but I remember reading somewhere that our Sun is among the first generation of solar systems that were born with enough heavy elements to make life based on carbon, oxygen, nitrogen, occasional iron etc. possible. That there first needs to be some generations of starts going nova so that the stars have g…

Another argument I heard, compatible with life being a fairly easy reaction;

A loglinear graph tracing the genetic complexity of life reaches zero about seven billion years. Obviously this implies an extraterrestrial origin of life theory. But it would also say life came into existence half-way into the big bang expansion and has been gaining complexity ever since. We are the result of this. But there's no reason to think there are other lifes that have that much of a head start. Thus it is not surprising that the manifestations of other intelligences haven't appeared.

http://pacojariego.me/2013/04/21/life-before-earth/

Re: When Are the Intelligent Aliens?

#33

Post by VLM »

ChuckMcM wrote: post #31
exratione wrote: post #11

Obligatory talking points associated with the Fermi Paradox: - It takes a very short time in comparison to the age of the galaxy for a single self-replicating probe to result in a descendant probe visit to every star. A few million years. This means that you cannot really argue plausibly that all civilizations fail to do this - it would take trivial effort for just one faction within just one advanced civilization to…

This is a good summary. One of the missing pieces is we don't know what the minimum set of combinational factors are to create "advanced" civilization. The scare quotes for advanced here are that two incompatible definitions for civilization quality compete for the nominative "advanced." In the current context advanced means we've developed machines that carry us into space, we can create habitats to survive in even…

One of the semi serious answers is you need a peculiar and somewhat unusual arrangement of land and sea to create a long series of oscillating ice ages every ten thousand years or so (to one sig fig), which is just the right wavelength to very strongly evolve intelligence and civilization. Without that intense adaptation pressure you don't get growth. With enough of it, you get us.

Re: When Are the Intelligent Aliens?

#34

Post by showerst »

Maybe I'm projecting too much human behavior on unknowns, but we've pretty much come to the conclusion that we when run into an uncontacted tribe of humans, we try to stay completely hands off.

Perhaps we shouldn't discount the possibility that's a universal evolutionary stage, and that there's just some sort of 'prime directive' type thing keeping any life from contacting us yet?

Re: When Are the Intelligent Aliens?

#35

Post by kabdib »

My favorite is: We're first. Assuming we make it out of the solar system and so on, then just imagine the practical jokes we get to play on future civilizations: Whoopee cushions crafted out of gas giants, mysterious "ruins" that have no bloody purpose at all, ancient stone tablets that end with "Assuming a spherical cow in a vacuum..."

Some archeologist, 20 millions years hence: "Oh god, not /these/ forerunners again."

It wouldn't be all bad, being first.

Re: When Are the Intelligent Aliens?

#36

Post by sage_joch »

exratione wrote: post #11

Obligatory talking points associated with the Fermi Paradox: - It takes a very short time in comparison to the age of the galaxy for a single self-replicating probe to result in a descendant probe visit to every star. A few million years. This means that you cannot really argue plausibly that all civilizations fail to do this - it would take trivial effort for just one faction within just one advanced civilization to…

Where are the macrostructures? We don't see Dyson spheres or other evident macroscale engineering.

This might be a stupid question, but could the Red Square Nebula be considered a candidate? http://en.wikipedia.org/wiki/Red_Square_Nebula

Re: When Are the Intelligent Aliens?

#37

Post by skreech »

bionerd wrote: post #20
skreech wrote: post #2

Considering how many life forms are on this planet, and how few of them who provide decent conversation, what are the chances of discovering Vulcans or Wookies? Most life we eventually discover might be more exciting to entomologists.

> Most life we eventually discover might be more exciting to entomologists. You say it like it wouldn't be fascinating just by itself. About 70% of Earth's surface is covered by water and more than 90% of the ocean still remains unseen by human eyes. We don't even know what incredible creatures could be living deep in the ocean let alone on another planet! Oh and by the way, even the fact that we can't have a "decent…

Didn't mean to sound condescending - it would be very fascinating, especially if we would find evidence of common ancestry and other similarities. Wouldn't exactly be the cantina in Mos Eisley, though.

However, as you point out, we live in the middle of an enormously rich biota need not stare at the stars to find new life forms. That's quite amazing.

Re: When Are the Intelligent Aliens?

#38

Post by exratione »

Tloewald wrote: post #28
exratione wrote: post #11

Obligatory talking points associated with the Fermi Paradox: - It takes a very short time in comparison to the age of the galaxy for a single self-replicating probe to result in a descendant probe visit to every star. A few million years. This means that you cannot really argue plausibly that all civilizations fail to do this - it would take trivial effort for just one faction within just one advanced civilization to…

The ground assumption in all of this is that we have some comprehension of the technological end-game / plateau. I.e. that a civilization far more advanced than our own will still care about solar energy and EMR communications. Who is going to build a Dyson Sphere for fun? We could be totally wrong about this. We probably are. The other possibility is that there's not much more technology for us. Can we build self-re…

To be clear, "self-replicating probe" includes all technologies that can transport, at a minimum, human genetic material, a record of all human science and technology to date, and creche-building technology to a distant star. So a few grams or kilograms of bootstrap molecular nanotechnology, computing material, shielding, some form of reaction engine, fuel for deceleration, and fired by the hundred from a solar-system-wide array of magnetic accelerators or accelerated by lasers. More likely the human genetic material will be absent in favor of emulated human minds.

Or think about actual humans, something large that we'd recognize as a starship, and a vast amount of antimatter. Much more spectacular, and much less likely, because of the amounts of energy involved in getting the job done - and all that just to ship things that could be build on site.

The point being that even if you say that we'll never build self-replicating technology (which is essentially the same as being a vitalist) then given the time scales involved - if every step in the probe network takes 1,000 to 10,000 years of resting time to build a complete organic human civilization before kicking off the next series of probes - it still requires a short time span to visit all stars in the galaxy in comparison to the age of the galaxy.

Re: When Are the Intelligent Aliens?

#39

Post by Luc »

VLM wrote: post #33
ChuckMcM wrote: post #31

Earlier quoted context omitted.

This is a good summary. One of the missing pieces is we don't know what the minimum set of combinational factors are to create "advanced" civilization. The scare quotes for advanced here are that two incompatible definitions for civilization quality compete for the nominative "advanced." In the current context advanced means we've developed machines that carry us into space, we can create habitats to survive in even…

One of the semi serious answers is you need a peculiar and somewhat unusual arrangement of land and sea to create a long series of oscillating ice ages every ten thousand years or so (to one sig fig), which is just the right wavelength to very strongly evolve intelligence and civilization. Without that intense adaptation pressure you don't get growth. With enough of it, you get us.

Interesting idea, I'd like to know more. Is 'The Ascent of Mind' by William Calvin what you are referring to?

http://www.amazon.com/exec/obidos/ASIN/0595161146/

Re: When Are the Intelligent Aliens?

#40

Post by abrichr »

Udo wrote: post #18
chongli wrote: post #16

Earlier quoted context omitted.

>Where are the macrostructures? We don't see Dyson spheres or other evident macroscale engineering. Everything we can see so far looks natural. This is more troubling than an absence of detectable communications. Assuming a Dyson sphere was nearby, how would we detect it? What would it look like? If it's able to make use of most of a star's radiation output, wouldn't that make it very difficult to see? It wasn't unti…

Even a Dyson sphere can't just swallow the star's radiation. It makes use of a potential gradient, which means it would have to radiate away some energy on the outside. This would probably show up as, say, a brown dwarf. Still, if it's not in our direct neighborhood the chances of us discovering it are even lower.

The Wikipedia article defines a Dyson sphere as a system of orbiting solar-power satellites meant to completely encompass a star and capture most or all of its energy output.
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