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Fraser
2009-Jun-05, 09:10 PM
While having lunch with colleagues at Los Alamos National Labs in 1950, physicist Enrico Fermi mused about the likelihood of intelligent life existing elsewhere in the Universe.* Fermi, one of the most astute scientists of his day, thought the size and age of the Universe means many advanced civilizations should have already colonized the galaxy, [...]

More... (http://www.universetoday.com/2009/06/05/so-where-is-et-anyway/)

thoth II
2009-Jun-05, 09:27 PM
The Sustainability Solution looks like the most logical one to me.

slang
2009-Jun-05, 09:55 PM
According to IMDB (http://www.imdb.com/title/tt0083866/trivia) Michael Jackson has one.

baric
2009-Jun-05, 10:36 PM
I thought the paper was terribly incomplete. There are several more obvious and likely explanations for the Fermi paradox, starting with the assumption that interstellar travel is possible.

They did not address that at all, other than repeat it as a given that populations would be able to expand across the galaxy much as they have done across the planet.

There are many reasons why interstellar travel is not possible:
-- too resource-intensive to justify
-- the fragility of biological life in interstellar space
-- high variability in planetary environments means little chance of a suitable destination


Then there are the standard explanation for the Fermi paradox:
-- evolution-safe zones in the galaxy are rare, hampering biological evolution
-- sapient life is extremely unlikely since it is not an evolutionary certainty
-- technological civilizations over-consume and collapse
-- technological civilizations self-destruct through violence and collapse
-- civilizations find that they cannot travel to the stars and turn inward. They are not broadcasting on channels at all, or channels that we can see

The Achilles' Heel in the "Sustainability Solution" is that it constrains resources on civilizations that are capable of interstellar travel. This makes no sense.

If Star System A has to resources necessary to evolve intelligent life and permit it to travel to other systems, then that life will typically be traveling to pristine, unused systems. These new systems will provide a tremendous boost in the resources available to the civilization, providing the fuel necessary for continued expansion to new systems.

In addition, resources are rarely "lost". They are generally transformed into states considered unusable (pollution & waste). A sufficiently-advanced civilization will develop the technology needed to recycle resources efficiently to avoid an economic collapse. We are seeing the beginnings of this in our own civilization.

Van Rijn
2009-Jun-05, 10:45 PM
This isn't a new idea. There have been discussions about this and related subjects on this board before. As I said in one thread:



No matter what a species wants to do, exponential population growth in our universe can't go on for very long (That's also one of the reasons why continual expansion doesn't make sense: Given any finite limits at all, population growth must be controlled, one way or another).


There have been calculations that if instantaneous space travel was available, and setting up new colonies was cheap and easy, then with a modest growth rate, a species could spread throughout the visibile universe in a few thousand years. It's a given that, with the speed of light as a limit, exponential growth cannot be sustained. That isn't necessarily an argument against interstellar colonization occurring, but it isn't a reason for it, either.

Ultimately, beyond the basic physical limits, the practical limits to interstellar expansion would be difficulty and expense. If it is cheap and easy, it is far more likely to occur than if it is expensive and very difficult.

Jeff Root
2009-Jun-06, 11:15 AM
I agree with baric and Van Rijn. Baric's first three listed possible reasons
seem the most likely. His "technological civilizations over-consume and
collapse" appears to be the same thing as the sustainability problem.

If a species (or the whole range of species required for a biosphere) has
the ability to reproduce large numbers rapidy -- which most terrestrial
species do -- then it will do so when conditions support that rate.
When conditions no longer support the high rate of reproduction, the
rate will fall. If conditions change again, the rate will rise again.

-- Jeff, in Minneapolis

gfellow
2009-Jun-06, 04:18 PM
Nice article. I published the same conclusion in some depth here:
http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Publication date: Mar 27, 2004
Verification: http://web.archive.org/web/*/http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Should I be getting credit? :surprised

baric
2009-Jun-06, 05:34 PM
I agree with baric and Van Rijn. Baric's first three listed possible reasons
seem the most likely. His "technological civilizations over-consume and
collapse" appears to be the same thing as the sustainability problem.

Similar, but not the same thing.

If you accept the premise that technological civilizations *are* able to expand through the universe, as the discussed paper did, then the overconsumption problem disappears.

When you expand into new systems, you are gaining the additional resources needed to continue the expansion. Therefore, there is no need to posit a sustainability problem until the habitable systems are exhausted.

gfellow
2009-Jun-06, 06:23 PM
...But what if nature universally hard-wires all "intelligent life" to perform a function and self-destruct, the destruction being part of a biospheres rejuvenating cycle?
http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Being a booster for the Homo sapien species, I don't really like the idea because it is so abhorrent, but having thought of it, I felt it deserved an airing.

TRUTHisnotfacts
2009-Jun-06, 06:48 PM
The problem with having time travel machines and or thermal hydro electric or thermal radar advanced flying cars from other worlds is simple by the time they get to there peak this may have took place .

Comet 05%
pole shift 05%
Planets star expanding 10%
war 80%

baric
2009-Jun-06, 07:30 PM
...But what if nature universally hard-wires all "intelligent life" to perform a function and self-destruct, the destruction being part of a biospheres rejuvenating cycle?
http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Being a booster for the Homo sapien species, I don't really like the idea because it is so abhorrent, but having thought of it, I felt it deserved an airing.

If anything is "hard-wired", it is simply the tendency of life to mindlessly expand into all available environments.

Humans are very, very different life-forms than anything that has come before in that we alone (on Earth, anyway) have developed the intellectual capacity to understand our biological place on Earth and within the context of evolution of life. We are not mindless! In addition, we have the ability to alter our evolutionary fate if we are able to collectively make wise choices as a species. There is no other animal on the planet that remotely has that chance.

For humans to survive as a species in the long-term within this single system, we need to learn to control our growth. But if we are able to expand to other star systems, then the need to stifle our reproductive impulses can be deferred until some much later date.

Van Rijn
2009-Jun-07, 02:25 AM
For humans to survive as a species in the long-term within this single system, we need to learn to control our growth. But if we are able to expand to other star systems, then the need to stifle our reproductive impulses can be deferred until some much later date.

No, barring cheap FTL travel (which appears physically impossible), and even assuming heavy expansion into the solar system, moderate exponential growth (population and economic/physical) can't continue for more than a few centuries.

Expansion to other solar systems (assuming it is practical) would allow growth, but it wouldn't be exponential.

Van Rijn
2009-Jun-07, 02:35 AM
Nice article. I published the same conclusion in some depth here:
http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Publication date: Mar 27, 2004
Verification: http://web.archive.org/web/*/http://www.goodfelloweb.com/nature/ideas/seti_faliure.htm

Should I be getting credit? :surprised

I don't see any mention of the exponential growth issue on that page. It appears to be the "civilizations blow themselves up" idea, which has been around for decades.

Mind you, the exponential growth issue is old too. I wouldn't claim credit because I've mentioned it a few times. Most of the ideas kicked around in Fermi/Drake discussions have been around for a long time.

gfellow
2009-Jun-07, 02:47 AM
have developed the intellectual capacity to understand our biological place on Earth and within the context of evolution of life. We are not mindless!

This is difficult for me to argue with, because I'm a full-fledged Homo sapien booster. But for the sake of following the thought process, yes, as individuals we appear to be unique, and we know this because we are Humans.
What if, in erroneously assuming we are not part of a greater life-cycle we are caught our own blind spot?
Imagine an intellect observing the Earth, might it not believe it was merely observing luminous crystal-like entities spreading across the landmasses within a biosphere? Might such an entity might not miss our intellectual prowess?

Are we capable of stopping ourselves from extracting carbon from the ground?
Can we stop proliferating nuclear weapons?
These are questions that presently go unanswered, but the weight of history and Human behavior ought not to instill us with unbounded optimism.

Might such an entity not merely marvel at the repetitiveness of nature in all its endless variety - and wonder how long until we delete ourselves in a radioactive carbon-consuming holocaust, all for the long-term betterment of the biosphere? As I wrote in the paper I referred to,

The eon between the mass extinction of the dinosaurs and the present is a mere 1/70th of our planet's existence - or to put it in another way, roughly one year out of the lifetime of a human being. If the planet were alive and cared about its biosphere, it might consider this span of time a mere inconvenience.
Within this time-scale, let us consider the ramifications of our massive thermo-nuclear extinction: The biosphere would have access to all that carbon we extracted in the form of coal and oil. Carbon that, until we came along, had been silted under, trapped away from interacting in the biosphere as it once had.
The radiation would ensure accelerated random mutation allowing for a greater variety of species to proliferate.
In short, come back 65 million years later, and our species handy-work could be appreciated in all it's glory; a richer, more varied and active biosphere for the Earth.

This cannot but help force the question:

What if this is the sole purpose of sentience? That if this is an inevitable pattern of extinction by civilization-building species repeating itself endlessly, for ever, everywhere in the Universe - An infinity of species evolving sentience, fertilizing their biospheres, then self-destructing? There would be no super civilizations, merely a temporary emergence, like a blossoming flower.

baric
2009-Jun-07, 04:28 AM
This is difficult for me to argue with, because I'm a full-fledged Homo sapien booster. But here: Yes, as individuals we appear to be unique, and we know this because we are Humans.
What if, in assuming we are not part of a greater life-cycle is our blind spot? Imagine an intellect with was looking down on the Earth, it might it not believe it was merely be observing luminous crystal-like entities spreading across the landmasses within a biosphere? Might such an entity might not miss our intellectual prowess?

That's a question formed from a highly speculative proposition. It's not really answerable.


Are we capable of stopping ourselves from extracting carbon from the ground?

Yes, we are capable. Will we do it? That remains to be seen.


Can we stop proliferating nuclear weapons?

Absolutely, and we now have a president in the US who is committed to this very issue. Will it be enough, or will we actually have to use them again before we realize they're not worth keeping?


These are questions that presently go unanswered, but the weight of history and Human behavior ought not to instill us with unbounded optimism.

Oh, I agree with that completely. There's very little in our past to give us optimism but, then again, we've never actually faced the threat of global extinction before this past century. It's a new problem, so the lessons of the past may not apply.


Might shrug such an entity not marvel at the repetitiveness of nature in all its endless variety - and wonder how long until we delete ourselves in a radioactive carbon-consuming holocaust - all for the long-term betterment of the biosphere?

There has never been such a holocaust before. Why would an external entity presume it is inevitable? How did this entity avoid it?

baric
2009-Jun-07, 04:32 AM
No, barring cheap FTL travel (which appears physically impossible), and even assuming heavy expansion into the solar system, moderate exponential growth (population and economic/physical) can't continue for more than a few centuries.

I agree, and in fact we may have already passed the balance point toward which we'll need to retreat in the coming years.

We have not yet even begun to harvest the remaining resources in our system, so I'm not so quick to put a cap on how much further we can go before we hit a wall. The growth may not be exponential, but I wouldn't completely rule out interstellar travel just yet.

gfellow
2009-Jun-07, 05:16 AM
There has never been such a holocaust before. Why would an external entity presume it is inevitable? How did this entity avoid it?
Well, as I said, I'm not keen on defending this train of thought, I find it rather disturbing.
As to holocausts, I'm sure you are aware of the geologic record. When referring to an external entity, I meant it in the abstract, observing our species from outside ourselves.

Why would an external entity presume it is inevitable? Why isn't SETI receiving signals?:)

Van Rijn
2009-Jun-07, 06:10 AM
I agree, and in fact we may have already passed the balance point toward which we'll need to retreat in the coming years.

We have not yet even begun to harvest the remaining resources in our system, so I'm not so quick to put a cap on how much further we can go before we hit a wall. The growth may not be exponential, but I wouldn't completely rule out interstellar travel just yet.

I'm not ruling out interstellar travel either, and I'm not assuming specific material limits to growth, just looking at the math of exponential growth. If we assume exponential growth, the growth will go nearly vertical fairly quickly. Optimistically, the resources of the solar system could give us a few centuries of exponential growth. Interstellar travel doesn't affect that, unless we assume cheap FTL travel, and even then, continuous exponential growth isn't possible for anything short of instantaneous travel in a competition free infinite universe.

Van Rijn
2009-Jun-07, 06:12 AM
Why isn't SETI receiving signals?:)

Do a search on the board, especially in the "Life in Space" section for dozens of ideas on that. There are many ideas, but little data.

eburacum45
2009-Jun-07, 08:35 AM
Growth will be dictated by the available technology. Already our population growth is dependent on technology; gather-hunter technology could only support a population on Earth of a fraction of a billion people. 1950's agriculture could only support a fraction of the population which modern agriculture could theoretically support, and in the future technology will increase the possible population still further. But eventually the limits of Earth's carrying capacity will be reached.

To continue growth past this limit, many leaps in space technology would be required; space mining, solar power collection, closed ecological life support, interplanetary transport. These are all theoretical possibilities at the moment, but nothing that breaks the laws of physics.

Once the easily available matter in the Solar System is converted into habitable structures, what then for growth? Well, then we can either attempt to convert the matter in the system which is not easily available, and/or we could expand into interstellar space. We might even be able to reduce humanity's ecological footprint by converting into electronic humans in computers, running on solar power. We might in fact do all three.

But each step requires an increase in technological sophistication, and each step has a final carrying capacity which represents an ultimate limit for growth. The mass of the solar system, the speed of light, and the ultimate density of information/entropy represent real limits which no-one could break, but which are probably well beyond the reach of any conceivable advances.

So yes, eventually growth will hit ultimate limits. Any ancient extraterrestrial civilisation might have hit these limits long ago.

slang
2009-Jun-07, 09:38 AM
[...] wonder how long until we delete ourselves in a radioactive carbon-consuming holocaust, all for the long-term betterment of the biosphere? As I wrote in the paper I referred to,

That's the idea behind at least one SF novel (http://www.amazon.com/Toolmaker-Koan-John-McLoughlin/dp/067169779X). Published 1988. And the background to some SF short stories from the 50's and 60's of last century.

Valkyrie801
2009-Jun-07, 10:35 AM
is in you.

We are not here as the evolution theory of Charlies Darwin...

Poor Charlies Darwin was the only one in all of human history who evolved from an ape...

It sounded so good that the whole scientific community fell for it.

Rift
2009-Jun-07, 11:22 AM
Are we capable of stopping ourselves from extracting carbon from the ground?


I come from a farming family, why would we want to do that? :P

Seriously though once the oil and coal are used up, we'll just move over to wind, solar, and wave power, and some others. Most of Iceland is ran on geothermal. And as population rates start to plummet in other parts of the world, as they have in europe and japan, I really don't see a problem...

As for nukes, I grew up during the cold war, I didn't think I would live to see 30. I turn 46 in July. The world is so intertwined economically now a full blown wwiii will never happen. Doesn't do you any good to blow up your customers. The few rogue nations now don't frighten me near as much as I was 30 years ago.

Read Collapse by Jared Diamond. Half the book is about cultures, both historic and modern, that collapsed, and the other half of the book is about cultures, both historic and modern, that should have collapsed and didn't. For every Easter Island, Norse Greenland, and Hati, there is a Tahiti, Iceland, and Dominica Republic.

Oh and Valkyrie, you really don't want to find yourself on that side of the argument on this board, you'll lose mercilessly. For one we didn't evolve from apes, cladisticly we ARE apes.

gfellow
2009-Jun-07, 08:14 PM
Do a search on the board, especially in the "Life in Space" section for dozens of ideas on that. There are many ideas, but little data.

Thanks Van Rijn,

It was actually a rhetorical question - follow the above thread and you'll see that the argument I linked to, suggests that all 'sentient' species might be manipulated by their biospheres to perform tasks that ultimately lead to the demise, that this repeats itself everywhere all over the universe - hence, no signals.

Just a horrid idea.

gfellow
2009-Jun-07, 08:18 PM
That's the idea behind at least one SF novel (http://www.amazon.com/Toolmaker-Koan-John-McLoughlin/dp/067169779X). Published 1988. And the background to some SF short stories from the 50's and 60's of last century.

Just goes to show there are few things that are new under the sun - I shall purchase and read - thank you!

gfellow
2009-Aug-02, 05:23 PM
That's the idea behind at least one SF novel (http://www.amazon.com/Toolmaker-Koan-John-McLoughlin/dp/067169779X). Published 1988. And the background to some SF short stories from the 50's and 60's of last century.

Thanks so much, Slang. Ordered John McLoughlin's "Toolmaker Koan" and read it.
The Author has a fascinating mind. I tried to find out more about McLoughlin, but there is surprisingly little about him on the web, not even on Wikipedia. Although he has published several science fiction books and several notable scientific books, he appears to be an enigma. Any suggested leads?

slang
2009-Aug-02, 10:20 PM
Thanks so much, Slang. Ordered John McLoughlin's "Toolmaker Koan" and read it.
The Author has a fascinating mind. I tried to find out more about McLoughlin, but there is surprisingly little about him on the web, not even on Wikipedia. Although he has published several science fiction books and several notable scientific books, he appears to be an enigma. Any suggested leads?

Glad you enjoyed it, I did too. No, I have no idea what else he published, I happened to pick this one up in a second hand bookstore.