Alek has a request:
1) While I'm far from a doomsayer, I'm wondering what is the best way to bet in favor of the world ending in 2012? Betting against is pretty obvious.
I am taking this to ask what is the most likely cause of the destruction of all civilization, circa 2012, and not how to collect on the bet, in which case he should read Pascal. (If the 2012 end of the world won't be a total surprise, any leveraged short position should do, but spend the money quickly!)
Here are some hypotheses, but my answer is: destruction of the earth by space aliens.
Here are previous MR posts on The Fermi Paradox. Rampaging space aliens would explain why we don't see more civilizations out there, plus predatory ways imply that contact is short-lived, thereby making our current lack of contact more likely in the Bayesian sense.
We could be living in some kind of "branching/splitting" theory where the highest number of branches come right before everything ends and for Bayesian reasons we expect to be right up against that final point. Still, why should we think that maximum branching/splitting is coming in 2012? After a Lakers threepeat, are there no more possible worlds to create?
The overwhelming probability from a nuclear exchange, at least circa 2012, is that it would remain limited, albeit highly destructive. A pandemic is unlikely to kill more than a billion people. A very large asteroid or a super-volcano explosion can be considered other leading contenders for world-enders.
A few nights ago Natasha and I saw The Day the Earth Stood Still, 1951 version. It's more a tract on foreign policy than science fiction and Klaatu of course is a stand in for the United States. I hadn't seen it in over twenty years and I'm astonished how well the movie captures and presages today's current mix of paranoia and utter unpreparedness, vis-a-vis "aliens." It works poorly when Klaatu dons the rhetoric and tactics of the United States in galactic affairs, combined with equally clumsy implied threats, backed by no moral authority but superior hardware. It's one of the scariest, and best, movies to watch in 2010, with a superb Bernard Herrmann soundtrack and it also has good shots of WDC in 1951. I won't give away the ending but a careful listen shows it's as pessimistic about the aliens as anything. Supposedly the movie deeply influenced Ronald Reagan and brought him to the arms control table.