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[personal profile] chris_gerrib
Yesterday, I was referred to this article on Fermi's Paradox, which hopes that no other life is found in the Solar System, by Tim O'Reilly. For the non-geek, Fermi's Paradox is a question asked by Enrico Fermi, the great physist, "if there are other intelligent lifeforms in the universe, why haven't we seen them?"

The first-cited article spends ten pages talking about the "Great Filter." This is the concept that some event is so improbable of occurrence or difficult to survive that we are the only intelligent species in the galaxy. For example, development of multicellular life may be so unlikely as to almost never occur. Another example may be that many civilizations arise, but they quickly succumb to some massive disaster. O'Reilly's contribution to the discussion is to suggest that Peak Oil is one such event. The idea here is that when we run out of oil, civilization will collapse. Even after or if civilization recovers, they will not be spacefaring because the cheap sources of energy have been used up.

This is by no means a new idea to science fiction fans, as a casual recollection of the literature will find examples of this concept at least back into the 1970s. At least some of those examples suggest inventive ways around the energy crunch. In truth, an energy- or resource-starved world would have even more incentive to go to space. In short, answering Fermi's Paradox with "peak oil" doesn't work for me.

Going back to the first-cited article, part of the problem of Fermi's Paradox is the assumption that we'd be able to observe and detect an alien civilization. This article suggests that detecting random ETA broadcast radio signals from a civilization won't work over even interplanetary distances. Other wild ideas, such as Dyson Spheres, would be difficult to detect at best.

The one "sure-fire" way of finding aliens is to assume that one race built a fleet of self-replicating Von Neumann machines, which would fill the galaxy in a few tens of millions of years. In my mind, this begs two questions.

1) Why build the machines? What benefit accrues to the builders?
2) Could we even detect the machines? There could be a battleship-sized ship or even a fleet of them in say, Saturn's orbit, and we'd not know about it. Nor could this fleet detect Earth's radio signature.

It's impossible to extrapolate from a sample size of one, so the answer to Fermi's Paradox will have to wait.

Date: 2008-05-07 05:03 pm (UTC)
From: [identity profile] will-couvillier.livejournal.com
Rememeber that article about the basement particle accelerator in Sweden (I think...been a while since I read about it)? Intelligence evolves all the time. Why else all the black holes?

Date: 2008-05-07 09:04 pm (UTC)
From: [identity profile] chris-gerrib.livejournal.com
You're the second commentor that cited black holes as signs of intelligence. Is there some book or article you're referring to?

Date: 2008-05-07 09:38 pm (UTC)
From: [identity profile] will-couvillier.livejournal.com
Just from what was written in that article. It was extrapolated that one of the results from operating that particle accerator would be the creation of a micro black hole. And since those things are very hungry and grow when fed, perhaps many of the black holes started out when the races there reached the technical level to build their own particle accelerators.

Date: 2008-05-07 09:43 pm (UTC)
From: [identity profile] chris-gerrib.livejournal.com
Did a little Google-fu and found the details, thanks.

Date: 2008-05-07 06:34 pm (UTC)
From: [identity profile] bdunbar.livejournal.com
1) Why build the machines? What benefit accrues to the builders?

There is not benefit - or not that we can see.

Guys living in the bush, on the edge of existence, have no time for hobbies. People who have 40 hour work weeks and extra income do things because they can.

I'm expanding a decorative pond in my backyard - it's only purpose is to be pretty and provide a home for fish I won't eat but like looking at. An unintended purpose is to provide a bird bath for songbirds, and drinking water for rabbits.

We can suppose that building a fleet of Von Neumann machines would serve no real purpose. But posit a civilization advanced enough to do so and it might be as trivial to them as my building a pond is to me, and done for the same reasons: because they can, because it's a nifty idea.

Or, really, maybe their wives talked them into it. Later came the justification ...

Could we even detect the machines?

Depends? If they are built for the purpose of seeking out new life, they might be built in such a way as to attract attention. Maybe that's where black holes come from - sign posts left by galactic probes that we're too dumb to understand.


Date: 2008-05-07 09:01 pm (UTC)
From: [identity profile] chris-gerrib.livejournal.com
A sufficiently advanced civilization could do anything. But you admit that, just like your fish pond, building a fleet of Von Neumanns is not likely to be high on anybody's probablity.

Date: 2008-05-07 09:52 pm (UTC)
From: [identity profile] bdunbar.livejournal.com
But you admit that,

Not for a civilization. I'm thinking that a VN 'explore the universe' project could be undertaken as a weekend hobby by a group of citizens from a highly advanced civilization.

A very advanced civilization.

It's all moonbeams and dust until we gather more knowledge. Bah - time to go home and dig some more on that pond ..

Date: 2008-05-07 07:45 pm (UTC)
From: [identity profile] jeff-duntemann.livejournal.com
We can't detect signals at interplanetary distances? We're still talking to space probes out past the orbit of Pluto. Amateur radio astronomers (note that this has nothing to do with amateur radio) can hear what we think are gigantic thunderstorms on Jupiter, without even a directional antenna. Gain antennas and cold amplifiers can do a lot of very interesting things. A civilization that could get a battleship-sized artifact from another star system into Saturn's orbit could damned well hear us. Interpreting what they heard is a separate challenge, but I don't think it would be rocket science to discern that they weren't listening to thunderstorms.

A peak oil crisis (or a bird flu crisis, or any number of other species of global crisis) might be just the ticket for goading the survivors into getting their lazy asses off the planet before the next crisis hits. The biggest single impediment to establishing space settlements anywhere in our system is our current culture. Peak oil does not mean no oil, and a humbled human civilization could work out ways to get a critical mass of people to Mars with the machinery to keep them alive and reshape the planet to our needs. It wouldn't happen overnight, but there's more to be done there than Kim Stanley Robinson's sleeping pill of a trilogy is willing to admit.

The obvious (and simplest) answer to the Fermi Paradox is that we really are alone, though why that should be is another very interesting and difficult question. I also think that many people underestimate the difficulty of crossing interstellar distances. Given advanced nanotech and an asteroid belt, it would be easier to create a whole new planet (or some sort of exotic habitat smaller than a planet) than go to even a nearby star system looking for a ready-made one.

I wrote an article about this fifteen years ago that may still be kicking around somewhere and could use revising.

Date: 2008-05-07 08:59 pm (UTC)
From: [identity profile] chris-gerrib.livejournal.com
The linked-to article was talking about broadcasts vs. focused communications. But your point was probably valid - if they could GET here, and in interstellar terms Saturn is HERE, they could find us.

Not sure we could find them.

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