Posted on 11/08/2001 7:52:53 AM PST by MeekOneGOP
Thursday November 08 09:37 AM EST
This puzzle, known as the Fermi Paradox, has burned up a lot of cerebrum cycles when scientists tried to reconcile the lack of company with the expectation that there are many advanced alien societies.
One possible explanation is that interstellar travel is just too costly. Consider how expensive it would be for us to populate another star system. Imagine sending a small rocket to Alpha Centauri, one that’s the size of the Mayflower (180 tons, with 102 pilgrims on board). Your intention is to get this modest interstellar ark to our nearest stellar neighbor in 50 years, which requires about 150 billion billion joules of energy.
No one’s sure what aliens pay for energy, but here on Earth the going rate is about ten cents a kilowatt-hour. So the transportation bill per pilgrim would be $40 billion. That’s a lot of moolah, a lot more than it takes to buy each emigrant a few thousand six-bedroom palaces and set him up for life. The fact that the trip is costly, in whatever currency, is reason enough to deter any alien society from trying to settle distant real estate. With far less expenditure, the extraterrestrials could pursue the good life at home.
Of course, if energy costs can be brought way down, for example with fusion or matter-antimatter technology, or by capturing more of the radiation spewed into space by the home star, this explanation might not hold water.
But even if the aliens can afford colonization, maybe they haven’t got the stamina to see it through. Subduing the Galaxy takes more than sending a ship full of restless nomads to the next star. The nomads have to settle that star, and then spawn pilgrims of their own. And those émigrés have to produce yet more settlers. And so on. If each and every colony eventually founds two daughter settlements (a pretty decent accomplishment), then 38 generations of colonists are required to bring the entire Galaxy under control. Even the Polynesians, who swept across the western Pacific domesticating one island after another, didn’t manage this. Maybe the aliens can’t do it either.
On the other hand, if a few of them remain committed to expansion, their project might still succeed – just more slowly.
Some researchers suggest that the Galaxy is colonized, but we just don’t notice. Arthur C. Clarke pointed out that truly advanced engineering projects would be indistinguishable from magic. Perhaps the evidence of alien presence is so beyond us that we simply don’t recognize it (somewhat like mice in The Louvre checking out the Mona Lisa). Another thought is that the aliens find Earth an interesting nature park, and have arranged matters so that, while they can observe us, we can’t observe them. The idea that we may be some aliens’ high-tech ecological exhibit is called the "zoo hypothesis."
These explanations, and a bushel-basket more, have been proffered to deal with the Fermi Paradox. Any of them might be true. Nonetheless, some scientists find them too contrived, too unlikely to work in every case. Will all the aliens find colonization too costly? Will they all run out of empirical steam? Are we so special that someone has really gone to the trouble to put us behind invisible bars?
Or is there a much simpler explanation?
Next time, we’ll consider some of the more obvious – if more disquieting – resolutions of the Fermi Paradox.
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I do think your on to something here. I think it was De Toqueville who said that democracies eventually decay into totalitarianism as soon as the majority figure out they can rob from the minority via the voting box. We went from a republic to a democracy in the 20th century. I see no signs we won't go down the drain entirely this century. Unless other civilations are immune to envy and class warfare, I see no reason why they would not follow the same pattern.
Those asteroid belts are located in the same plane in which all the planets orbit. Anyone could approach earth from "above" or "below" the orbital plane, and avoid all that debris.
First, we aren't waiting for them to contact us; we are listening to hear them talking to each other. If we have to wait for them to notice us and call, we'll be waiting by the phone for quite some time: it will take 30,000 years for our first signals to reach the center of the galaxy.
This is also the reason why I think we have not recieved in alien broadcasts. Or we may have recieved some alien broadcasts and thought is was just static because their forms of data encryption and data compression are to alien for us to understand.
The point here is that we haven't seen any signal at all. It's not a question of decoding it; it's a question of brightness. Any bright narrowband source at a fixed position on the sky would be counted as a candidate civilization.
The second is the fact that they would have to go through two asteroid fields to get to our planet, Earth. The first is the asteroid field that is right past Pluto. Then they would have to cross the asteroid field between Mars and Jupiter.
Patrick Henry is entirely correct, but it really isn't an issue in any case. Even if the aliens approached along the ecliptic plane--a good idea, since they could use gravitational slingshots and aerobraking around Jupiter and Saturn to shed momentum--the chance of them hitting an asteroid is vanishingly small.
The third is that from what we understand, Earth has no real special resources to speak of.
Same resources as are found anywhere else. If it's not worth coming here, it's not worth going anywhere.
Also, if any aliens recieving our, radio, televsion and internet broadcasts: They would think the human race was completely insane. Which they maybe questionably right.
God help us if they review our voting records.
You see where this is initially heading, the technology of the Mayflower, the technology of rocketry, some alien technology not yet even dreamed of by we earthlings ... too many likely antiquated perspectives are inherent in this thread premise. Our understanding of spacetime is still in its infancy.
We haven't unified the fundamental forces yet, or come up with a perspective that allows for such. Oh, we like to believe our current perspective will yield a GUT, but even Michio Kaku has some reservations when asked if superstring theory will unify all the fundamental forces in a useable equation; he expects there will be a next generation equation set that will be much simpler once we understand how to unify the forces.
Which brings me to another oddity in our perspective: it is my opinion that our current use of the term space and the notion that space is dimensional in point, linear, planar, and volumetric is upsidedown, that dimension space has expressions of complexity order, as in point=least complex, linear=slightly more complex, etc,; and I apply the same notion to time, as in dimension time with complexity expressions.
It is a different way to conceive of the dimensions we now perceive and into this different mix I would inject the notion that life is an variable expression of factors for dimesnion life, with 'perhaps' expressions such as will, emotion, mind for complexity expressions of dimension life. As such, our familiar life form is expressing the variables of dimension life in a carbon based atomic complexity, but it is possible that other base molecules could be the fundamental atom, and it is also possible that the complexity level we sense now as spacetime, now/here is slightly out of phase with other expressions of where/when. It would help to explain some of the phenomena recorded in the scriptures, such as the handwriting on the wall, in Daniel, or the visitations by Angels, or even the spacetime transcendence of Jesus after the cross.
[An aside: if there is a distinct dimension we might call life, from which the impetus for molecular manipulations eminates, that dimension would be naturally non-temporal and thus the life of anything would be 'eternal' from a temporal transcendence perspective. It may be that we are vaguely familiar with four dimensions: time, space, life, and spirit.]
Nope. There are always Klingons or Romulans, who say "up yours with your sissy Prime Directive."
In other words, if intelligent ETs are common, one or more of them will refuse to play by the "U.N." rules and come calling.
--Boris
Sigh.
They could come from a direction outside the ecliptic plane.
And the asteroid belt is not exactly a traffic jam. Most spacecraft will zip right through, without ever seeing a rock as big as your fist.
Ultra-powerful ETs who have solved the problem of interstellar travel would find the asteroid belt a laughably easy impediment. Indeed, NO impediment.
--Boris
Yeah. I don't like it, but after reading Rare Earth I am afraid I find this the most plausible explanation.
--Boris
Think back a few hundred years. Most of the population thought the world was flat and were totally unaware of the people living in Hawaii, and this was on our own tiny planet.
So here we are looking into a universe that contains billions (ok I'm sounding like Sagan LOL!) of stars. Many of them may be a possible harbinger to life. This life will look NOTHING like us. Even here on this planet compare a jellyfish to a giraffe.
Also the distances are so great and to date we have no reason to disbelieve what the equations that General relativity are showing us, No other life forms may be able to effectively travel outside of their own solar system.
I have a question for you. Has someone already come up with the theorem for time differential (I think that is the proper word) on Galactic scale?
If so, please tell me where I can find information on it.
What I mean is the different states of time (mass(+/-)+/-speed(+/-)=time) in relationship to different regions and locations in the Milky Way Galaxy.
Also, I don't think space travel between is going to our main. I think navigation is because when you travel from star system to start system, you will lose all points of reference, including time itself in relationship to where you were. Also, your star charts will become all but useless.
I have a question for you. Has someone already come up with the theorem for time differential (I think that is the proper word) on a Galactic scale?
If so, please tell me where I can find information on it.
What I mean is the different states of time (mass(+/-)+/-speed(+/-)=time) in relationship to different regions and locations in the Milky Way Galaxy.
Also, I don't think space travel between the stars is going to our main problem. I think navigation is because when you travel from star system to start system, you will lose all points of reference, including time itself in relationship to where you were. Also, your star charts will become all but useless.
I don't see how you can say these things as fact. We simply don't know such things for certain.
No problem. All pulsar locations in the galaxy will be stored in the ship's computer, and at any moment the ship can use their signals as navigational beacons. It will be no more complicated than zooming around on a computerized roadmap. So if it's navigation that worries you, relax. Start working on the propulsion system; that's where the real challenges are.
I'm sure it was nothing more than a supposition.
Well, they would if they expected to live indefinitely in the New World. But you're still missing the point about fuel. Already I've shown that essentially everything you want to bring with you is fuel. I'll even let you convert mass directly into energy. Here's the point: the faster you want to get there--by rocket or by bicycle--the higher the percentage of the mass of ship that must be made out of fuel. The less fuel you want to carry, the slower you have to go, so the more support equipment and supplies you need. There may be no optimum that actually permits a human being to make it to the nearest extrasolar planet.
The only way out is to have a ship that does not carry its own fuel, such as a Bussard ramjet. When we come up with a proof-of-principle for such a device, we can start to talk about it.
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