The Daily Galaxy gives us (compliments of Mike Treder) three possible explanations for the Fermi Paradox, the apparent absence of advanced civilizations in a universe that should be teaming with them:

We are (A) the first intelligent beings ever to become capable of making our presence known, and leaving our planet. At this point, there are no other life forms out there as advanced as us. Or perhaps extraterrestrial life does exists, but for some reason extraterrestrial life is so very rare and so very far away we’ll never make contact anyway—making extraterrestrial life nonexistent in a practical sense at least.

Or is it (B) that many advanced civilizations have existed before us, but without exception, they have for some unknown reason, existed and/or expanded in such a way that they are completely undetectable by our instruments.

Or is it (C) There have been others, but they have all run into some sort of “cosmic roadblock” that eventually destroys them, or at least prevents their expansion beyond a small area.

This is a pretty good breakdown, but I see no reason why options B and C should be exclusive. What if it's a 50-50 split? Half of the civilizations that come along wipe themselves out; half become so advanced that they are beyond what we can detect. Or maybe it's 90-10 in favor of civilzational extinction, or 70-30 in favor of civilizational advancement beyond detection.

Whatever the relationship between the numbers, if such a mix is true -- if a civilization inevitably meets one fate or the other -- the implication is that continual advancement is the only option. We can't stop where we are, building skyscrapers and computer networks; neither can our descendants, building Dyson Spheres and the like. We have to keep pushing on until we either shrink out of site or exit this universe altogether...or are destroyed in the process of trying.

In that case, the Fermi Paradox is really just the observation that nobody stops in the middle, and there probably aren't very many civilizations "in the middle" within detectable range of each other at any given time.

So how do we proceed? Should we assume the odds are 50-50? Maybe we should assume the odds are 80-20 against us. That would require us to use a good deal of caution, but would still offer us a fighting chance for pushing on.

Posted by Phil Bowermaster at 7:04 AM | Permalink | Comments (6)

I'm an E.T. skeptic. The Fermi Paradox is the reason. The Fermi Paradox asks, reasonably, if intelligent life arises easily and often, then where is everybody? As old as the galaxy is, and considering the possibility of self-replicating Von Neumann probes, we shouldn't be able to swing a cat without hitting a Vulcan - or at least a robotic emissary.

The most likely answer attacks the premise of the paradox. Intelligent life (at least intelligent life that gives rise to interstellar civilizations) doesn't arise easily or often. We're alone. At least in this galaxy.

Some who have accepted this explanation of the Fermi Paradox have posited a depressing reason for E.T.'s absence - perhaps civilizations that reach our level of development tend to self-destruct.

But the great filter for interstellar civilizations doesn't have to be in front of us. There is a good argument that it is behind us.

[According to Professor Watson from the School of Environmental Sciences at the University of East Anglia] Solar models predict that the brightness of the sun is increasing, while temperature models suggest that because of this the future life span of Earth will be ‘only’ about another billion years, a short time compared to the four billion years since life first appeared on the planet.

“The Earth’s biosphere is now in its old age and this has implications for our understanding of the likelihood of complex life and intelligence arising on any given planet,” said Prof Watson.

“At present, Earth is the only example we have of a planet with life. If we learned the planet would be habitable for a set period and that we had evolved early in this period, then even with a sample of one, we’d suspect that evolution from simple to complex and intelligent life was quite likely to occur. By contrast, we now believe that we evolved late in the habitable period, and this suggests that our evolution is rather unlikely. In fact, the timing of events is consistent with it being very rare indeed.”

We're probably alone, but self destruction doesn't have to be our fate. If we can make it through the next century or so, we stand a fair chance of settling the galaxy.

Posted by Stephen Gordon at 3:12 PM | Permalink | Comments (9)

An intriguing post on The Daily Galaxy:

The 1.5 Gigayear Technology Gap

Some of the world's smartest astronomers estimate that some of the more advanced technological civilizations in our Milky Way galaxy may be 1.5 gigayears older that Earth (that's 1.5 billion years older). In other words, the search for extraterrestrial life is not going to end with us meeting the Hollywood kind of alien. ET or the Asgard (from Stargate) are not going to be who we first meet. Instead, we’ll be greeted by highly evolved robots.

Yes, in other words, Battlestar Galactica has got at least one thing right. The hit Sci Fi channel show’s bad guys are, unlike most other Sci Fi shows, highly evolved robots that have turned on their human creators.

But first, the real story.

"There are two kinds of encounters with aliens you can have," said Seth Shostak, senior astronomer at the California-based SETI Institute. "Either you pick up a signal, or you pick them up on the corner. But I think it's safe to say that in both instances they will be synthetic. They will be artificial constructions."

Continue reading "Looking for the Smart Aliens" »

Posted by Phil Bowermaster at 6:41 PM | Permalink | Comments (3)