image: azrainman
Next April 1st-themed Item: In the mood for total planetary annihilation?
Strange to say, there is a veritable genre these days of websites, discussion boards and other resources dedicated to the burning question of how to destroy the Earth. These fun-lovin' folks don't mean the little stuff that merely ends humanity -- emit a lot of CO2 and cook the place until it looks like Venus, detonate enough (surprisingly few, actually) warheads to trigger a nuclear winter -- they mean galactic-style doozies that conclude with no Earth whatsoever. Not even the surface-sterilized chunk that is our common fate at the end of that celebrated film "Beneath the Planet of the Apes." Rather, we're talking about an empty swath of orbital space where planet 3 used to be.
As a kind of grimly humorous exercise -- and, let's face it, just because homo sapiens thinks this way -- one can ask: How hard would that actually be? The possibilities are fascinating, in a nihilistic kind of way; feel free to post your favorites here. FQXi even gets in on the fun this week, with a piece by astronomer / fellow prognosticator of doom Kate Becker. Read it while there's time.
image: jurvetson
My personal favorite from our various final acts: Total Existence Failure. This scenario is premised on the idea that if an actual particle can spontaneously cease to exist -- as virtual particle pairs do all the time -- then there is some non-zero possibility that all particles comprising the Earth could do so, simultaneously. Turns out we were wrong about that whole "conservation of matter" thing. Earth vanishes in a statistical fluctuation.
Other charming possibilities: a wandering micro-hole oscillates through the planet, consuming mass as it pendulums around our core; the same, only with the hole created by accident at the LHC; vacuum energy detonation (those virtual particle pairs again); "eaten by von Neumann machines"; and -- another favorite -- "systematically deconstructed." (The humanities nerd in me has to point out that the posters really mean "dismantled," but let that pass.) The big idea on this one? We know sizeable chunks of Earth can be blasted into orbit. That's probably what formed the moon. So why not blast all of it into orbit, forming a debris ring around a non-existent center?
On a more moderate scale, we ourselves are the clear front-runner in the list of impediments to our own survival, followed by some rapidly mutating virus that stumbles into the international air-travel niche. Leaving the local perils aside, though, our galactic neighborhood provides more than a few colorful disasters that could erase humanity with close to zero lead-time. Many folks are aware of the danger of impactors, though an asteroid wouldn't need to be anywhere near as large as the Texas-size remnant headed for Earth in "Armageddon" to do us in. (Was that movie really about the fear of Texas?) More immediate, and in some ways more flashy, is the nearby gamma ray burst.
image: Gluemoon
We pick up a couple of these ever week on satellite -- all, thankfully, in somebody else's galaxy. At least so far. No one knows just what they are, though the prevailing wisdom has collapsing black holes pegged, and possibly the collision of two neutron stars. Depending on proximity, were one to go off in our neck of the spacetime, the radiation blast would likely strip off our ozone, if not our atmosphere, if not our surface itself (!), sterilizing things all the way down to the extremophiles. That would indeed be an April Fool's Day to remember.
And after that? Things would be quiet on Earth for a change. Then, in a few billion years, the descendants of Deinococcus radiodurans would be setting up their first telescopes and peering out at the peaceful stars.
image: jared