Radio silence & geoengineering
May 4th, 2009
Here’s another letter to The Economist, this one from 2006-11-27. I didn’t expect them to publish it, and they didn’t. But I had to get it off my chest (hey, that’s why I post here, too).
SIR –
Tongue-in-cheek, David Crawley suggests a defence against alien invasion [Letters, 18 November]. If it were possible to evaluate and counter the capabilities of aliens, such a plan might be wise. Unfortunately, any hostile aliens able to bring a force to our planet are likely to be so advanced as to make any defence we might offer entirely ineffectual. (We have no way to estimate the likelihood of such an attack, as we have no information about the distribution of intelligence in the universe. ) Yet the absence of radio signals from other stars is, if anything, ominous, as we have known since Copernicus that Earth’s situation is in no way special or unique – if our neighbor’s transmissions have been suppressed, perhaps ours will be as well.
That said, a defence against global warming [the real subject of Mr. Crawley’s letter] is not in the same category – there are remedies such as increasing the Earth’s albedo (reflectivity) – a requirement that future roads and rooftops be painted white would be an inexpensive start, or reducing the sun’s heating of the Earth, for example by placing large inflatable sunshades at the Lagrange point between the Earth and Sun. Others will have better suggestions. We do not need to freeze in the dark.
This guy Crawley sent a sarcastic letter criticizing governmental action on “the risk of something really catastrophic” resulting from global warming, because “only a minority of scientists perceive this as a threat and the costs of such a defence are enormous”, then comparing it to the results of an alien invasion.
I thought it was a lousy analogy, and said so above. I should have avoided getting side-tracked with a discussion of Berserkers (scary and interesting as that may be, The Economist is not ready for it).
May 26th, 2009 at 6:45 pm
First! 🙂
I must nitpick your comment that “we have known since Copernicus that Earth’s situation is in no way special or unique”.
Since Copernicus, we have known that Earth was not the center of the universe (though for a while, we thought the sun was). As time went on, we learned that our location in the universe appears to be nothing special. We’ve also never found evidence that physical laws are different here compared to elsewhere.
But that doesn’t mean we won’t find something, someday, that makes us unique. So far, there’s no evidence of life (let alone intelligent life) elsewhere. While it seems hard to believe that there’d be nothing out there, we do have respectable scientists suggesting that we are the only intelligent life. They frequently use arguments that boil down to “absence of evidence is evidence of absence”, but they claim that it’s valid to apply that in this case.
I don’t believe it myself, and I even more strongly hope it’s not true. But so far, evidence points to our being unique.
May 26th, 2009 at 8:44 pm
Of course, we could be unique in some important way, but in the absence of evidence, there’s no reason to think so.
Which leaves us with Fermi’s Paradox – where are they? Either something astronomically unlikely has happened here on Earth or something is preventing those other civilizations from sending out signals (and visiting us, for that matter).
During the Cold War, a popular idea was that civilizations reach a certain level of technical competence and then blow themselves up with nuclear weapons. Something like that could still happen, but we’ve been transmitting for about 100 years now – long enough that the absence of similar transmissions is strange, unless civilization is extremely rare in the universe.
Personally, I hope we’re alone. The alternative is a high probability that something is coming to shut us up.
Not that the universe cares what I think.