Galactic Colonization Limited By The Inability To Expand Exponentially

June 23, 2009 by Miranda Marquit, weblog
Galactic colonization is likely to be limited by the Fermi Paradox. Image credit: NASA

( -- For more than 50 years, many have taken the so-called Fermi Paradox to indicate that the existence of intelligent alien civilizations is an impossibility. However, a recent re-examination of the paradox points out that, rather than discounting the spread of an intelligent civilization, the Fermi Paradox merely points out that advanced civilizations with exponential growth are unlikely to exist.

Enrico Fermi speculated (during a lunch break) that the age of the universe, as well as its size, meant that there should be a number of advanced societies keeping Earth company, in a galactic sense. Growth of these civilizations would be exponential, Fermi implied, and therefore if they existed, we would have encountered them already. Ergo, advanced alien societies must not exist, since their expansion hasn't brought them into the range of our detection.

A new take on the Fermi Paradox, though, changes the equation a bit. At Pennsylvania State University, two scientists suggest that the key to the paradox is the assumption that civilizations would colonize the universe at an exponential rate. Jacob Haqq-Misra and Seth Baum point out that finite resources preclude exponential expansion. Technology Review offers a look at the problem of exponential growth:

"The problem is that this kind of growth may not be possible, and they look at Earth as an example. For any expansion to be sustainable, the growth in resource consumption cannot exceed the growth in resource production. And since Earth's resources are finite, and it has a finite mass and receives at a constant rate, human civilization cannot sustain an indefinite, exponential growth."

This means that, if we decide to colonize our galaxy, Earth's civilization will be unable to do so at an exponential rate. If you apply the realities of Earth to possible alien civilizations, then it becomes much more likely that there are other advanced societies out there. Like Earth, though, they are limited in their expansionary capabilities. Perhaps there are thousands of alien societies out there, just trying to effectively colonize their moons or settle on planets in their solar systems. It is possible that, if that is the case, the question of existence of intelligent alien life may not be answered in our life times.

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5 / 5 (11) Jun 23, 2009
It seems to me that if you send one generation ship to a planet, which then over the course of it's colonization produces more than one generation ship, then you would always have exponential growth. Of course a civilization can't grow exponentially forever given the limited resources of a single planet or even a single planetary system, but given that they ought to be able to expand to other star systems, presumably with at least one planet or moon that is hospitable to their civilization, then they would be able to expand rapidly. The only way that would fail would be for there to be some factor that limits growth, like some powerful "galactic police" that doesn't allow for more than a certain amount of territory for any one civilization, or some sort of interspecies pact forbidding growth faster than some certain rate. Of course, we could be in some sort of galactic nature preserve as well. There are any number of possible reasons for a lack of space faring civilizations. Maybe all the advanced ones were wiped out in some catastrophic war, or some sort of local anomaly prevents some of their technology from working properly, so no-one has come here.

In short, speculation is useless. We need to get out there and find out ourselves rather than staring at our navels.
5 / 5 (4) Jun 23, 2009
I'd say earls had the same reaction I did, anyone who thinks about this kind of thing can come to that conclusion.

I also think us not knowing of them is a pretty insignificant way of saying they're not there.

I can think of endless reasons why we wouldn't know about them that don't require any kinds of studying and are just as plausible.

otto said what I was thinking in a much smarter way.
3.4 / 5 (9) Jun 23, 2009
I would expect the most rapid expansion of any civilization would be in the first few dozen generations past the point where interplanetary travel becomes possible. The only limiting factors become the availabilty of resources, the proximity of viable worlds, and the speed of travel. If graphed you could see a large bump after this point until the next level of equilibrium is reached, which would likely be orders of magnitude greater than a single planet's equilibrium.

Humans do not "overpopulate" - Modern developed cultures are all trending towards 0 population growth. There is a natural equilibrium that will arrive on this world, and the pressure to find new lands will be increased.

Those who use simple models of human population are misled to think that our populaiton will grow without change until we run out of resources. The protection against this is economics - As the staples of life become more and more expensive, the birth rates will decline. There will be no catastrophic precipice - This is why birth rates in the developed world are already low and declining. As the cost of living increases for third world countries, they too will zero out their birth rates and the world will stabilize.
5 / 5 (1) Jun 23, 2009
1. They dont want contact with us

2. Theyve only made contact with a select few

3. They see no reason to expand outward


These arguments don't hold much value. You are assuming that every single alien civilization would choose exactly the same principles and make the same decisions. This is not very likely to happen. Even if a majority of them choose a specific course of action or there is some interspecies government, there will always be dissenters that go a different route. This would happen even in our own species, if the human race expanded out and found an alien civilization, you will have people who want to follow the prime directive and don't interfere, want to manipulate them without them knowing, want to announce our selfs to them and try and help them, want to conquer them, want to blow them up in case they become a threat, want to sell them Pepsi, want to spread various religions or that word of god or whatever.

We would only need 1 person of the 6.6billion (much more by then) to violate the rule in an obvious way. The only way would be if there was some kind of way to implement a complete and total control over every species and individual to stop them interfering.

Maybe a giant impenetrable 'cage' around the solar system to keep out the nasties and fake the energy from the rest of the universe (to stop radio signals being sent or some nutter from blowing up suns in a specific order and announcing to everyone at one or something). Of course the cage would have to be completely impervious to all the other races technology and such.

I think the real reason we haven't found anything is the age of the universe, the age of the human race and the time required for space travel. Limits on exponential growth might explain why the galaxy isn't crawling with aliens but it doesn't stop deliberately sending out self replicating probes to visit each star system, reproduce, and carve your initials on a planet to announce your exinstance (or something more hightech).
not rated yet Jun 23, 2009
...why is finite Solar Constant a limit for them but not for greenie economy?

I don't think anyone has ever claimed that the amount of solar energy that could be harnessed is infinite. But the potential there (if it was presently economical) is more than we could consume, at present.
3.8 / 5 (4) Jun 23, 2009
Any beings able to reach us across interstellar distances would probably be unrecognizable to us, virtually invisible until and unless they chose to show themselves.

I doubt they would be interested in us at all, and would be exploring other dimensions, if there are any, or creating new universes tailored to their needs, if that is possible.

If we meet them at all, we'll meet them somewhere "on the other side" of things. (You know, like in the Apple iPhone store.)

The only exception would be an extremely unlikely chance encounter between two species at the same developemental stage. An extreme long shot, but you never know.
5 / 5 (3) Jun 23, 2009
Civilizations don't expand exponentially because the population doesn't increase exponentially. The rich countries on this Earth are almost stagnant in population growth. Some countries are even shrinking because not enough kids are born. Once we can reach the stars we will be so rich that our population will remain relatively stable. No more than 2 kids per couple.
So we might explore some star systems and have small colonies, but there just wouldn't be the population increase for exponential growth.
not rated yet Jun 23, 2009
wow, an article for that.
5 / 5 (3) Jun 23, 2009
Exponential growth is possible for exploration purposes over a limited time. If we sent an advanced probe to a star system even a sub-light speed, that probe would arrive and search for usable resources. If it finds them, it builds a new set of probes and sends them off to the nearby stars. In the meantime, it beams back its findings to its parent home world.

Such a system of probes could visit and catalog every star system in a galaxy in a few million years. The technology is, for now, beyond ours. But that THAT much beyond. I'll bet we could do this by 2100 if not 2050. And it requires very little resources from each star system visited.

So no, limited resources aren't a good solution to Fermi's Paradox. Yes, it's likely why some expansionist version of the Borg doesn't occupy the entire galaxy. But you don't need to colonize a star system to go there, learn about it and use its resources to move to the next system.

If humanity is on the crux of building such a system of galaxy-roaming probes, there's no reason to assume that every other advanced civilization hasn't already done this or something more advanced. Chances are extremely good that our star system has been visited by advanced probes again and again and again.

The only reasonable conclusion one can infer from the Fermi Paradox is that the aliens who know we exist don't want to talk to us for some reason. Maybe they're waiting for us to become advanced enough to find them. Chances are, that won't take all that long either! If the Kepler mission finds a world with water vapor, oxygen and ozone in the atmosphere of a small world as far out from the habitable zone as is Neptune... it'd be hard to explain that through natural means!
3.7 / 5 (6) Jun 23, 2009
I think the real reason we haven't found anything is the age of the universe, the age of the human race and the time required for space travel. Limits on exponential growth might explain why the galaxy isn't crawling with aliens but it doesn't stop deliberately sending out self replicating probes to visit each star system, reproduce, and carve your initials on a planet to announce your exinstance (or something more hightech).

My thoughts exactly. When we visited the moon we left a flag and a plaque.The two Voyager probes carry welcome messages, and they may very well be the first things that an alien race a million years or so. IMHO the only reason we have never met or spoken with aliens is that we just haven't been around long enough. Our race may or may not exist by the time they receive our messages however...too bad.
3 / 5 (3) Jun 23, 2009
Consider this: a truly advanced civilization might well have 'conquered' death -- beit through bioengineering or through cybernetics.

If individuals live practically forever, then procreation directly adds to total headcount, as there is virtually no compensatory shrinkage due to deaths. Each individual might procreate at least once, just to have that experience -- meaning that over time, the population grows without bounds up until it bumps against energy/resource constraints... or until it completely loses all interest in procreation.

This would be a relatively slower process, when compared to the human population explosion in the last few thousand years, but we're talking about billions of years (the universe is some 13.5 billion years old...) It's all but guaranteed that unless life on earth is some nearly-impossible accident, then there should've been life in our galaxy long before our solar system formed ~4.6 billion years ago.

There's got to be some REALLY OLD geezers out there by now; problem is they've seen it all and they know it all -- so to them we aren't the least bit interesting in the slightest. On the other hand, they'd be so advanced that to us they'd be all but undetectable. After all, the more advanced you are, the more efficient you are: so you wouldn't be leaking massive amounts of energy into space, that Earthlings could detect with their telescopes... (which is why I think the whole SETI idea is boneheaded.)

And all of that is even assuming that the "universe" we know and love is all there is. We might well be suffering from some good ol' geo-centrism: for all we know, more advanced aliens tend to depart our quaint little spacetime cradle in favor of some more enticing hyperspace environs where the grown-ups come to play...
5 / 5 (2) Jun 23, 2009
And would they want to, given that they had an entire new planet to settle, and presumably historical records of the dangers of overpopulation and industrial pollution?

It just so happens the "overpopulation" and "industrial pollution" coincides with the most rapid advancement of living standards and technology mankind has ever known.

I get to live twice as long as my great, great grand parents. I get far more spare time and far less back-breaking labour.

The greatest irony is that the malthusians/club of rome types tend to be the biggest opponents of nuclear energy, especially breeder reactors of any kind. That inherently makes them supporters of coal power.

I think Amory Lovins expressed the reasoning behind this view most clearly when he said: "Complex technology of any sort is an assault on human dignity. It would be little short of disastrous for us to discover a source of clean, cheap, abundant energy, because of what we might do with it."
1 / 5 (2) Jun 23, 2009
And Douglas Adams proved that the population of the universe is zero...
2.5 / 5 (2) Jun 23, 2009
It would take one arrogant S.O.B. to honestly believe that his species is the only intelligent one in the entire universe. In our primitive world, we have the U.N. The galaxy would obviously have something of the same nature to resolve conflicts without war and to coordinate their plans for the galaxy. What do you think this galactic version of the U.N. would say to somebody who wanted to stop by and visit our quaint little backwoods planet. NO WAY!!! That's a wildlife preserve! The only way we'll find alien life is if we venture outside of the wildlife preserve into the next solar system.
2.8 / 5 (4) Jun 23, 2009
There is a perfectly good reason aliens aren't visiting us. They are only interested in intelligent life!
5 / 5 (1) Jun 24, 2009
I stand by the ideal that , someday, we will meet ourselves and declare first contact.
1 / 5 (1) Jun 24, 2009
Advanced intelligence exists at higher levels of vibration. We exist at the lowest level of vibration. Once our vibration increases we will be consciously welcomed into the the galactic community. It is our consciousness that has not evolved to accept what is already there.
not rated yet Jun 24, 2009
As the internet clowns say First!. Maybe we are what they'll call in years to come "The Ancients", someone has to be first.
5 / 5 (1) Jun 24, 2009
My take on this is a simple problem of scale. Animal intelligence as we now know it, is but a rather shortlived stage. We emit radio waves and waste radiation for a thousand or 2 years, get more clever and less redundant in terms of energy/matter, and voila... What are the chances of us detecting that in the last 50 years or so?

In another 1000 years, will we be interested in doing so? I'd rather be an immortal, concious, exploring and learning lightbeam... Mingling intimately in unimaginable ways. ;)

not rated yet Jun 24, 2009
Enrico Fermi speculated (during a lunch break) that the age of the universe, as well as its size, meant that there should be a number of advanced societies keeping Earth company, in a galactic sense. Growth of these civilizations would be exponential, Fermi implied

The problem here is the assumption of exponential growth. The limit is not resources as those would also grow exponentially or at least could as long as one solar system was capable of producing more than one colony. The real limit is the speed of light.

To grow exponentially without limit would eventually require a civilization to expand faster than the speed of light. This limit is the main reasons I suspect that there is no way to beat the speed of light. If there was Fermi might be right.

Then again someone has to be first. Maybe we are it.



Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.

QubitTroll will be released from my sig at the end of June.
not rated yet Jun 24, 2009
We should be able to grow at the same factor as surface of a sphere with constantly growing radius, I don't know the mathematical term...
not rated yet Jun 24, 2009
The radius growth would be limited to the speed of light. Don't remember where I got this limit one from but I didn't come up with it first.



Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.

QubitTroll will be released from my sig at the end of June.
3 / 5 (2) Jun 24, 2009
In my eyes we shall consider survival on this planet first before fetching for the stars.

Our current `behaviour` seems more likely to cause mass extinction than building conditions to colonise a galaxy neither linearly nor exponentially. If even our food supply remains so utterly dependent on fossil fuels than today it is easy what the world will look like if oil prices hit again levels of 140 and beyond (having partially desabilized housing markets followed by the financial sector) and states won't be able to spent billions again.

Have a look on Richard Heinbergs Videos on "The peak of everything" on youtube - this will make a little clearer that it is not likely to keep Kurzweils vision of double exponential growth rates (and devolepement of biotechnology and nanotechnology as well as robotics an anti-aging and galactical colonisation) alive if we continue like we do. Bold acts are an absolute requirement before dreams like galactical colonisation are considered any further.
5 / 5 (1) Jun 24, 2009
The argument is based on "planetary chauvinism," so named by Gerard O'Neill in describing the assumption that planets are the only proper places for humans to live.

Interesting that you used the classic L-5 Colony design to illustrate this article. That was O'Neill's answer to the question: Where is the proper place for a growing technological civilization? Space.

Between accelerating technology, solar power, asteroids, comets, and moons, there is plenty of energy and material resources for an exponentially growing civilization.
5 / 5 (1) Jun 24, 2009
..In short, speculation is useless. We need to get out there and find out ourselves rather than staring at our navels...

Absolutely. We know almost nothing. In fact, one of the things we DO know is that a host of Black Swans will be discovered, as we proceed further into the cosmos.

1 / 5 (1) Jun 24, 2009
"The radius growth would be limited to the speed of light."

More or less true (though, if an advanced civilization builds spaceships capable of traveling at 3/4 c, then two of those traveling in opposite directions will increase the distance between them, as measured by a stationary observer, at a rate of 1.5 c...)

More to the point, our galaxy is "only" about 100,000 light years in diameter. Even if you started on the very outskirts, and even if you 'crept' across it at average of a mere 0.0001 c (about 30 km/s, the speed of a slow-moving meteor), you will have still completely canvassed it within a mere 1 billion years. If you started close to the galactic center, then you can do the same in about half the time (since rather than traversing the diameter of the galaxy, you will only have to cover the radius.)
4.5 / 5 (2) Jun 24, 2009
Advanced Civilizations can function within limited resources for exponential growth. The Fermi Paradox makes one other assumption which may not be true. This assumption is that humans as they expand will consume more resources. What if they could expand without consuming so many resources, as well as travel outward amoung the stars in a virtual way?

Hypothetical "science" fiction like proposal would be to digitize humanity (we already are going in that direction) upload our conciousness and physical bodies into cyberspace, hence Second Life, social networks, digital broadcasts, genome project.

Then afterward, expand outward and only instantiate a physical presence when necessary, mostly using robot remotes, shielding for our digital environs and expand outward to the stars. Populate a planet only when it has advantages for survival and move onward, eventually maybe mastering instantaneous travel through high energy wormhole physics, if possible. Unless this takes us to alternate realities.

Somewhat simple really, once we acquire the technology, whole races could travel on viral expanding "microstarships" to the stars, time dilation could be used to slow down the cpu cycles on the starship so that the perceived journey for consciousness would be short.

Most of the ideas are here (I shamelessly plug myself)
1 / 5 (1) Jun 24, 2009
Possibly the main reason we haven't made contact with the aliens is our own fear. Our government made a decision to shoot first and ask questions later fifty or so years ago. This may have precluded us receiving all kinds of extremely valuable knowledge that we will now have to wait indefinitely for.
3.5 / 5 (2) Jun 24, 2009
Maybe there really is no paradox. When the enormous cost (energy requirements) of interstellar travel is taken into account, it appears unlikely that any civilization could ever colonize even a small portion of the galaxy. Unless someone can invent a faster-than-light drive that runs on fuel cell batteries, we will never be able to visit even Alpha Centauri.
2 / 5 (4) Jun 24, 2009
Zero point energy is a crank idea. Oh, it sounds good if you don't look to close. The key problem with it is quite simple. Its the energy of the vacuum EVERYWHERE. The energy of points with mass is even higher. Energy can only be used by getting to flow from high energy to low energy.

Where the heck are you going to find a point of lower energy than the vacuum energy? No differential then there will be no energy flow.



Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.

QubitTroll will be released from my sig at the end of June.
not rated yet Jun 24, 2009
Billions of years ago the first civilisation swept across the galaxy converting all matter into computronium. However, they decided that it was only fair to put aside some of that new computing capacity to allow "natural" evolution to continue. We are living in that simulation.
3.7 / 5 (3) Jun 24, 2009
It seems many are assuming that our state of "advancement" over the last couple hundred to a thousand years is in some way the natural state of things. I think we should consider the whole of human(the only advanced tool-making society locally) history before speculating on some "natural" rate of advancement or expansion. We've leapt quite far fairly quickly here of late. I'm not sure it's reasonable to assume that said leap is inevitable across all creatures. After a couple billion years looking we've only seen it once. Hmmm.

Secondly, I think many are discounting the extreme difficulty, danger, financial cost and political difficulty of any long-term space faring venture. Look at we humans. Here, in our glory, at the peak of two colassal centuries of great though painful advancement, we can't confidently mount a timely effort to our own moon, a pea-shooter spit away.

Thirdly, one must take into account the possibility that anywhere near lightspeed flight may be impossible. The density of the interstellar medium itself becomes an obstacle well below these speeds.

Taken together, I believe it is highly possible that there are other intelligent societies out there in every direction, but they simple haven't yet had the time or (like us) the political will to come anywhere near our nieghborhood.

I'm sure they're all lovely creatures. But the likelihood of our ever meeting is remote, extremely, extremely remote.

BTW, any radio signal(radiation) arguement holds no water. The technology creating the signals and the technology to detect them are too short lived(a couple hundred years on the outside) to likely ever overlap.
not rated yet Jun 24, 2009
I would like to think Nicola Tesla did not die in vain.

Well then, let me reassure you on that that point. Tesla did not die in vain... he died in New York City.
2.3 / 5 (4) Jun 24, 2009
'In physics, the zero-point energy is the lowest possible energy that a quantum mechanical physical system may have and is the energy of the ground state ... which is non-zero.' -wiki.

Which is my point. You can't move energy from the lowest possible state to an area of higher energy. Not without spending more energy than you get out. You can pump heat out of ice but it cost energy. More energy than the heat that is moved.

How else you gonna explain all them Nazi flying saucers?

Uhnnmmm, they never existed? Yeah I think that might be it.

I would like t
o think Nicola Tesla did not die in vain.

He created the system used today for the US power grid. The way people talk about him you would think he was the combined incarnation of Nemo, Merlin, and Harry Potter. Giant Tesla coils just aren't a practical way to move energy from the generator to the user.



Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.

QubitTroll will be released from my sig at the end of June.
2.5 / 5 (2) Jun 24, 2009
Any one who thinks we are alone in the vastness of space is just a bit naive. Anyone who thinks that going into space whould be to lonely forgets that humans have been venturing into the unknown since the start of things. All we need to go is a habitable place to go to. There will always be those who will gladly leave what they know to go in search of something else. Some explore, some migrate and settle. They only survive if there are enough resources, and by chance avoid the inherent dangers of leaving the familiar for the unknown. While we cannot use human values or emotions to describe the behavior of an alien species, if they have any kind of technology it must be due to curiosity and where curiosity exists in a species...stuff happens!
2 / 5 (4) Jun 25, 2009
This is the dumbest "insight" I have ever seen. Growth would be exponential until habitable worlds become scarce. I agree with the first commenter though that Fermi's paradox makes too many assumptions (how about intent? how about Man gets as smart as the native Americans and realizes that quantity isn't the same as quality - that we should live in balance with nature?) and we won't know really until we get out there.
2.5 / 5 (6) Jun 26, 2009
1. Virtual particles from the lowest possible energy state cause black holes to evaporate.

Which has nothing to do with the concept of Zero Point Energy. Its mass conversion. Any mass in the black hole is converted to energy on the outside of the hole.

Zero point energy is based on the Casimir effect. The problem is readily apparent. The Casimir effect pushes two plates together a barely measureable amount. To cycle it you push the plates apart, ooops that used up all the energy the Casimir effect released. And a little more.

2. Tesla was murdered.

Yeah right. Its so hard to believe he had a heart attack because he was so young. A mere 83 years old. A spring chicken. A child really. Hardly anything at all in comparison to any number of mythological people.

3. Nazi bell-technology saucers never existed ... Prove It!

The FBI is hiding the information I need. Probably in Area 51. They want people to believe in Nazi saucers so they will forget about the Little Green Men.

Sorry if your original post was joke. Its so hard to tell here. Even the real scientists seem to be enamored with becoming a Mad Scientist after they retire. Some others clearly aren't waiting for retirement.

Otto are you practicing to write short stories? You might try making a little longer. Perhaps studying Fred Brown would be a good idea. He was the master of the very short story AND he wrote about Little Green Men from Mars.



Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.

QubitTroll will be released from my sig at the end of June.
not rated yet Jun 26, 2009
If someone invents a truly novel technology (Vernor Vinge's "bobbles"?; Larry Niven's ramscoop star drive?; Star Trek warp drive; antigravity?; controlled hydrogen fusion, etc.), we may be able to colonize nearby star systems. But, with technology we currently have or can reasonably extrapolate, the reaction mass and energy requirements for interstellar travel are completely out of reach. Somewhere, I read about an estimate of the cost of a starship that indicated the cost would exceed years of gross planetary product. The human race would need an enormous incentive to commit the level of resources required to build and launch a starship.
not rated yet Jun 26, 2009
A supercivilisation will by definition be so different from us (Homo Sapiens Sapiens 1.0) that it is futile to try to derive their motivations and plans from our situation.
They will certainly modify the body and brain, and eventually, in a mere hundred thousand years or so, abandon the concept of biological bodies altogether. They may even prefer interstellar space (and the occasional "brown dwarf" system), since the ambient temperature makes their component parts superconducting. We could be well inside an expansion front for such a civilisation and never notice it.
That said, the most likely case is that we are *among the first* technological civilizations in the local galaxy group, with a million light years to the next neighbour. The reasons for my pessimism can be found in the book "Rare Earth: Why Complex Life Is Uncommon in the Universe" by Ward & Brownlee.
not rated yet Jun 26, 2009
This argument makes no sense unless you have FTL starships. You colonize a nearby star, in time the colonists colonize another star and so on--any one star only ever launches a few colony ships. The only resource limit that's likely to matter in this case is population.
not rated yet Jun 26, 2009
Growth may stop here and there. There may be moments that we say, "this is good, I like it where I am". All of humanity may get addicted on some web experience reality.
1 / 5 (1) Jun 27, 2009
Advanced civilizations if they exist, would have gone into higher-dimensional space-time manifold long ago after transforming their physical bodies into a massless bodies of energy and light.
They might have ascended to highest levels of consciousness where the universe of unity and its infinite variegatedness is one and the same.

If humanity wants to evolve faster along with machine consciousness they require radical expansion of consciousness. In order to give birth to self-identifying machine consciousness, we ourselves need to evolve consciously first.

You can find some new human consciousness expansion tools and techniques here at
2 / 5 (4) Jun 27, 2009
Having read some of the comments it appears that somebody forgot to lock the door.
Our own experience shows us that there is a natural progression from simple to complex in all life forms we have encountered.
This would appear to be a natural process
If it is natural here it should be natural everywhere.
Within the limits our our own planet we find life forms thriving in environments hostile to us (deep ocean vents)
We therefore know from our own planet that life can develop in environments hostile to us.
Due to that it is my view that life will be a common occurrence throughout all of space.
BUT it does not have to be like us.
The next problem is distance and speed.
Even at the speed of light we will take 4 years to our nearest neighbours and they may not have a planet suitable for us.
Let us assume that we find a suitable world relatively close to us, say 50 light years (astronomically that is virtually our front doorstep).
If we gain light speed the people who start out will die before they reach their destination.
Those who do make it will have lived all their life in space and will have to adjust to gravity upon arrival. Whether they can do this and survive is something we still have to learn.
Presently we measure our propulsion speeds in tens of thousands of kilometers per hour
We have to achieve speeds of over one billion kilometers per hour.
Unless some of the science fiction concepts come to our rescue it will be a long, long, long time before we make any appreciative journeys.
At this point in time we are hog-tied to our planet.
Distance and speed are our enemies.
If other civilisations are similar to ours in that we make technological advances whilst socially and emotionally we remain barbarians, then they are likely to have brought about their own demise.
Whilst we here are pondering our ability or otherwise to travel out among the stars we live on a world that has finite resources and we continue to breed like rabbits and we will eventually outbreed the planets ability to support us.
We may be the first earth species to bring about its own extinction.
If we do that then we really do not need to worry about interstellar travel.
If there are intelligent beings who have conquered the problems of distance and speed and if they in their evolution have become civilised they would surely look upon us as a very backward and primitive species, for that is what we are.
The best we could hope from them is that they would observe us as we do animals in zoos or that they might do as we do and take one or two for research purposesWe delude ourselves that technological advancement equates to civilised.
Sadly it doesn't.
1 / 5 (1) Jun 27, 2009
Correction, I meant if we gain near to light speed.
not rated yet Jun 27, 2009
In regards to early posts on whether aliens would care about us, I strongly believe that if there is other 'technologically advanced' life in the universe, they would be extremely interested in us if they found us.

Technology requires resources, mathematics, and science. Assuming they are intelligent enough to develop mathematics, they would need a very strong curiosity about the natural world to initiate the scientific method.

However, being scientists, they would probably want to avoid influencing what they are studying until we see them. At least, that's my opinion on this aspect of the Fermi paradox.
1 / 5 (1) Jun 27, 2009
does the fermi equation have a variable to indicate the likelihood a civilization would be expansionist? Earth history is filled with civilizations that were not expansionist. even if it were in our genes to be expansionist we will soon be able to alter our dna to remove it. What if the expansionist gene and expansionist drive come with unnaviodable tradeoffs such as aggression or war and we decide as a planet we are better of not being expanionist?
not rated yet Jun 27, 2009
we could even be an experiment (like we do with laboratory mices)well defended and observed from distance, or we might just be a civilization in the extreme of a universal map (just like the europeans had to wait 1700 to reach Fiji)

i think the possibilities are not even immaginable.
not rated yet Jun 27, 2009
and i believe there's plenty of predator races out there (just like the nature shows us, pradators hunting for food)

as well as Humans more developed and powerful (just imagine our Race evolved for 500.000 years in another galaxy)

3 / 5 (2) Jun 27, 2009
why no contact ?

we understood only today that IF we could step back and leave the Indians of America alone (instead than invade them and destroy them) they would have developed their own way

(simply think, when we arrived with Columbus in America or in the Pacific Islands, with a simple flu we caused thousand of deaths, our imported animals - rabbits or unwanted rats which caused local fauna problems)

we want the contact, but they might avoid it
or who is at our same level doesnt have the knowledge to try it (like us)

we as humans are causing a bit too many of extintions (from primitive tribes, to animal species to natural environments)

1 / 5 (1) Jun 27, 2009
Yeah if I was an alien I wouldn't want to get infected with human ewwww
not rated yet Jun 27, 2009
"Some others clearly aren't waiting for retirement"

You can say that again. But as the old saying goes why put off tomorrow what you can do today. :)
not rated yet Jun 28, 2009
There are any number of possible means to travel faster than the speed of light. My choice would be a time traveling spaceship, you needn't travel very fast when your trip is nearly instantaneous time-wise. Time travel is also as impossible as faster than light travel. Many things we take for granted today were once considered impossible though so it's just a matter of time until someone stumbles across a means to exceed that speed limit.

It's hard to imagine a civilization able to travel and expand thru the stars not containing at least a few misfits or social scientists who'd find us interesting enough to want to study. They may not choose to do so openly or they might have done so in the past and had impacts that we don't see. And it's possible they'd 'leave a light on' for us, sending out primitive radio waves so that less advanced species could detect it even if they'd moved past the need for that tech eons before.
4 / 5 (1) Jun 28, 2009
I would imagine that like any new colony, a space colony would enjoy explosive growth and vitality and within a few generations would be ready to launch a new colony. And the parent planet would continue to ship off it's undesirable malcontents to new colonies to keep the majority happy. You'd hardly need exponential growth for other civilizations to have matured enough to be knocking on our door, given the time scale involved. Assuming they're somewhat similar to us and that planets like ours are in short supply, they'd be likely to investigate at some point. And if they're advanced enough I doubt we'd even be aware of their presence unless they chose to be noticed.

In my opinion, there are a few possibilities. Outsiders are not allowed or are kept away by some means. We are unappealing for some reason, maybe too primitive at this point, as in an adult trying to have a meaningful conversation with a three-year-old. They're here now and they're either covert by choice or through government cooperation. They were here and they got bored and left. They're so different from us that we have nothing to interest them. Our solar system may have some feature that makes it hard for them to travel here. I think it's a sure thing there has been other intelligent life and that they've colonized other star systems. But we may only find their fossils when we begin to colonize for ourselves since so many things could wipe out even a space-borne civilization.
not rated yet Jun 28, 2009
why we can't detect alien tech or a civilization?

Here's what I thing of. Come to think of it, the universe has been there for billions of years and ALIENS may have lived a few thousands of years after and therefore, they might have the knowledge to have a technology that can't be detected by ours.

If you consider a factor of the distance away from any contacts, maybe, each civilization living in such planet or system has different speed of gaining knowledge. For instance, like our Earth, Europe in the past or maybe today has very fast technology, In the Americas they only have the use of nature as feats of engineering, 100% religious beliefs,(well you know that)etc. In Asia, there is the "native style" of tech and there's the spiritual use in its society.

So, if we apply the same thing to the universe, then, it's still the same.
not rated yet Jun 28, 2009
To see all the world in a grain of sand.... Exponential growth may be in our mind's spirit. We may only travel in simulations of 2045. We might colonize space, but not really.
1 / 5 (3) Jun 28, 2009
To even SAY, much less assume into a peurile argument that resources would be scarce to an arbitrarily advanced alien civilization is at the height of idiocy.

This article has THE most poorly constructed "argument" against the paradox I've EVER read...
1 / 5 (3) Jun 28, 2009
1. They dont want contact with us

2. Theyve only made contact with a select few

3. They see no reason to expand outward

-Theres no reason to expect that a mature species would be spewing excess radiation beyond waste heat. Theres no reason to think they would value unlimited expansion beyond that needed to ensure survival, over a static existance of continued refinement. Only overpopulaters like ourselves automatically think of room to expand. This quality would probably present a threat they would want to either manage or eliminate. The fact that we still exist could mean we are being managed, husbanded; or that the urge to expand naturally fades.

4. Theres no reason to think that this system is not already occupied by beings who have migrated to the outer reaches where it is quiet and safe, and who value nothing more about us than our company.

The problem with this argument is that it does take more and more resources to continue to "do" whatever it is advanced civilizations do. Even if it's just pure scientific research.

They will have to expand. This has been addressed before. There MIGHT be a civilizatoin that doesn't but it would not resemble us much (not that it has to), but since we're the only example we know of to think otherwise would be going against the only data point we have.
2 / 5 (4) Jun 28, 2009
The universe to an adult species could be like America- no matter where you go it's all the same- so why bother? As long as they clean up their neighborhood- no unexpected novae, rogue singularities, cosmic strings, or virulent lizard cultures, why bother to go anywhere? Stasis can be comforting if you're not concerned with aggressive procreation. Yeah I'm pretty old-

Again this argument is pretty flawed. For a species to gain intelligence they're probably going to be curious almost to a fault (look at us). Staying home and being intelligent is like being a couch potato and being healthy...the two are pretty mutually exclusive.
1 / 5 (3) Jun 28, 2009
why no contact ?

we understood only today that IF we could step back and leave the Indians of America alone (instead than invade them and destroy them) they would have developed their own way

(simply think, when we arrived with Columbus in America or in the Pacific Islands, with a simple flu we caused thousand of deaths, our imported animals - rabbits or unwanted rats which caused local fauna problems)

we want the contact, but they might avoid it

or who is at our same level doesnt have the knowledge to try it (like us)

we as humans are causing a bit too many of extintions (from primitive tribes, to animal species to natural environments)

The problem here is the immense problem of hiding evidence of your existance from an exponetntially advancing culture. Very soon we'll have telescopes that can resolve details on planets in other solar systems.

Even if we didn't have contact with Indians, how do you hide a jumbo jet contrail passing over a village?
not rated yet Jun 28, 2009
All along the way they would find new resourses..after all is'nt it why they would go in the first place? but alas..lightspeed is a tough nut to crack for any lifeform...anywhere.
1 / 5 (3) Jun 28, 2009
All along the way they would find new resourses..after all is'nt it why they would go in the first place? but alas..lightspeed is a tough nut to crack for any lifeform...anywhere.

Very true, but this is merely a speed limit...or a time limit. It says nothing about HOW the expansion would take place.

There has been math done that suggests that even at sublight speeds humanity could colonize the entire galaxy in about ten million years or so...blink of an eye stuff...
not rated yet Jun 28, 2009
MM..I like that! merely a speed/time limit! and pack lots of eyedrops! but the best part...colonize...hmmm.
1 / 5 (2) Jun 29, 2009
Exponential growth is relative, due to the relativity of space and time.

If you are a colonist on a near-light speed ship which travels to a distant star, then in your own reference frame, only a few days pass for the entire trip, whereas "everywhere else" in the universe years or even millenia can pass.

I explored the pros and cons of this about a year ago in my "interstellar sputnik" deep space probe scheme that I came up with, as well as another post on interstellar population growth for near light speed colonists.

In other words, in the reference frame of a colonist who was on a ship at 0.99c, they only observe a few hundred days pass to cross the entire galaxy. This mostly positive and negative acceleration time. Now 0.99c is an extrem example, but similar huge effects become very significant starting around 0.86c, and speeds of 0.1-0.5c are currently unattainable, but are not at all unrealistic considering the possibility of fusion or anti-matter. Anyway, to the colonist on the 0.99c ship, they see a few days pass, but earth and everyone else has had eons worth of time to expand. Quite literally, a ship can leave earth at 0.9c and arrive at a planet ages AFTER a 0.99c or 0.999c colony ship has been invented, lifted off, and landed on a still more distant planet...(I proved this previously.)

In other words, by the time the first colony ship reaches its destination, there may already be billions of humans living on that planet who are descendants of colonists who got there by travelling in a much faster ship which was created years or even decades(in earth's reference frame) after the first ship lifted off.

So, if near-light speed (0.5c or greater) is possible (and it is theoretically possible given enough anti-matter or enough fissile matter,) then "somewhat exponential" growth of a galactic or even inter-galactic civilization actually IS possible.

I say "somewhat exponential" because it isn't perfect, as nothing is, but conceptually, you could have tens or hundreds of colony ships leaving earth and reaching their destinations tens, hundreds, thousands, millions of years in the future as observed by earth, (but merely a few hundred days or less as observed by the colonists.)

What is the return on the investment, from Earth's point of view? not materials or resources, but rather knowledge, especially astronomy and physics, but also all forms of knowledge and technology. A population of 100 billion has ten times as many minds as that of 10 billion, a population of 1 trillion or more is 100 times, etc. So more brains, more technology. More observatories and probes throughout the galaxy, more knowledge and more accurate astronomy, especially for long distance measurements.

Anyway, if you think about it, the time doesn't really have anything to do with exponential growth or non exponential, especially since time is relative.

If we simply look at the issue in terms of habitable planets and moons, then arbitrarily exponential growth is very easy to obtain.

Earth sends out "N" colony ships to "N" habitable bodies.

Each colony started by those ships eventually sends out "N" ships, and so on.

This is exponential growth, but it is respect to bodies inhabited, not time.

Since time is relative, exponential growth with respect to time would itself be relative, which means that growth which appears exponential with respect to time in one reference frame (earth's) may not appear exponential with repsect to time in another (the 0.9c colony ship which was "passed up" by the 0.99c ship)..
3 / 5 (2) Jun 30, 2009
Why leave the mothership when she gives us everything we need.

Just like this debate we don't need to be in the same physical space to communicate with aliens and combine knowledge of the universe.

Humans may not even be able to handle the degradation that will occur with intergalactic travel. We are much more likely to build robots that connect directly to our cyber reality and send them out than our take the risk of doing harm to our fragile bodies.

If we spend so much money to extend our lives for the purpose of living longer it makes sense that we will be even more risk averse to putting ourselves in harms way by travelling through space.
not rated yet Jul 01, 2009
Seti unfortunatly is a joke.

We haven't detected any other civilizations because if they exist, they do just what we do, listen but don't talk.

To send and receive, requires exceeding the background and internal noise levels at the receiver. This is why your cell phone can only go so far.

Transmitting omnidirectionally would require thousands of times more power than transmitting directionally, and to transmit directionally would require knowing where the aliens are.

Of course the usable distance also is dependent on bandwidth, the more information in the signal we send, the less distance it can be received, unless even more power is used.

To send to an alien civilization, even directionally say 50 light years away, would require more power and continuity of effort than our civilization is capable of.
Transmitting continuously over thousands or millions of years at these power levels is unlikely.

The chance of us and any other civilization transmitting these power levels, in the correct direction, and looking to receive messages from the other in the correct direction, happening simultaneously with these kind of distances is slim to none.

What's worse is if the next habitable planet is 1000 light years away.

The only reason to travel to other systems would be to meet other aliens in person.
There are more than enough resources, both in energy and materials, in our solar system to last us for millions of years.
Just look at Saturn and its moons, Jupiter and its moons, Mars and its moons, the asteroid belt, and the Kuiper belt for materials.

The sun produces essentially unlimited energy if harvested in space, which of course is where all the dirty manufacturing would occur.
not rated yet Jul 01, 2009
To send to an alien civilization, even directionally say 50 light years away, would require more power and continuity of effort than our civilization is capable of.
What makes you say this?
not rated yet Jul 01, 2009
I did a quick and dirty calculation, and if I didn't make a huge blunder, if the transmit antenna had a divergence limited by diffraction and a dish size of 100 meters at both ends, it looks like about 30 gigawatts of transmitted power would be needed at 50 light years.
This will depend on bandwidth.

Maybe someone who has the time could do this.
See this link for the math.
not rated yet Jul 02, 2009
My guess would be that they would use a laser, preferably X-Ray or higher. X-rays would diffract less and would cut through any intervening dust. Even the best collimated lasers would still fan out greater than the diameter of the solar system (according to my quick and dirty calculation:)) which might have advantages in actually aiming the thing. I don't know enough about telescope resolutions now or in the forseeable future, but I guess that they would be good enough to pick up a powerful laser beam greater, and perhaps a lot greater, than 50 light years. But that is a guess.
not rated yet Jul 19, 2009
Fermi Paradox vs Drake Equation. It all sounds about as useful as 'prove God doesn't "exist"' to me. Irrelivant since no one has claimed that "he" does "exist".

To be taken exactly as seriously since I can't even gleen what time interval "exponential" is on.
AND regardless of brick walls like light-speed, or whether it's a distance at all or a sort of exponentially increasing population on the surface of an expanding balloon blown up by exploration.

Anyway.. just thought I'd do a drive-by with a better idea.
Why should traversal be such and arduous decider if simultaneity occurs at all?
Nassim Haramein - Crossing the Event Horizon

Let's say consciousness is a universal singularity. And these "advanced aliens" understand that and physics limitations perfectly like we understand the difference between binary and analog.

Why would they ever traverse anything when they could instantaniously BE (so to speak) a person of earth or anywhere else?
The only reason to traverse is to satisfy growth for the sake of survival, if theyre advanced at all, and never growth for the sake of growth, so automatic "exploration" would also be moot.

They would simply undrestand this place as well as we.

"Then according to the man who showed his outstretched arm to space;
He turned around and pointed, revealing all the human race. I shook my head and smiled a whisper, knowing all about the place."

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