Part 4: Conclusion
Now, before I can wrap this up, I feel there are a few ideas floating around that I haven't really addressed. They fall into the category of "nonsense," and hence there is little need to dissect them as with the others. However, I think they deserve mention - some for their longevity, some for their popularity, some for their outright insanity. So, without further ado, here's the list of "runners up" (see bibliography for sources) :
1. Resonance Cascade
Your star sign indicates that now is a good time to buy canned foods, bottled water and a crowbar.
Well, this one certainly takes home the "best runner up" prize, at least for popularity and longevity. It is also interesting in that a lot of people came up with this idea independently - I think that I thought of this without ever having seen one the many, many comments on the internet implying this as a possibility. It is, of course, meant purely in jest, but I feel obliged to remind everyone: no, the LHC will not open any portals to any kind of border world, Xen or otherwise. No, you need not clutch your crowbars in paranoid fear. Yes, you should probably worry about the dissolution of our civilisation and its replacement with an authoritarian super-state, but that's for other reasons.
Plausibility: none whatsoever.
"LHC SATANS [sic] STARGATE 2008"
This is almost certainly one the crazier ones, although probably not the absolute craziest.
The gist is: the LHC invokes God's wrath ("too deeply they delved there..."), or allows Satan to return to earth or something like that, and then the world ends. Not something I think we need to worry about, mostly because of my strongly atheistic worldview, but partly because of the "it would have happened already" argument. I don't think we'd need to build a particle accelerator to wake a god up to the fact that mankind ought perhaps to be judiciously squished.
Plausibility: not even wrong.
"ATLAS = Atlantis?"
The claim is that, long ago, in atlantis, some scientists tried to understand the universe completely, and this was Bad, because of some other New Age-y stuff that I don't remember, and hence we shouldn't do it again (which the LHC will do). I think the biggest obstacle to this, from a assume-it's-sensible perspective is the fact that, if the atlantean scientists already did whatever the Bad Thing was, I don't think we need to worry about it happening again, because the world is still here (unless it's stackable, of course).
Plausibility: still none at all.
If you don't use the collider, you can't have any antimatter. How can you have any antimatter if you don't use the collider?
So some people read too much Dan Brown and decided "hmm, the evil-conspiracy stuff is off the wall, but the physics sounds perfectly feasible." Or something like that. Anyway, the gist here is: the LHC is used to produce large quantities of antimatter. This is then used the nuke cities and so forth. Not very pleasant, and not very plausible either, simply because the LHC doesn't work that way. You can't stand next to a collision zone with an antimatter trap, waiting for some to pop out. Not to mention, antimatter would take billions of years to produce in anything approaching the quantities described in Angels & Demons and antimatter will always take more energy to produce than can be obtained by annihilating it with matter5.
Plausibility: ever so slightly higher than zero. So far, the only one of these that could even possibly work is this one.
To summarise the long and often winding path of this series of nodes: the LHC poses really only a miniscule threat to life on earth. Ultimately, the LHC is not doing anything the universe hasn't done before. It's merely bringing the cosmic ray collision to a laboratory so it can be studied more carefully, so that we may inch closer to a complete understanding of the universe that spawned us. In the absence of a convincing argument showing the LHC to be a threat, it makes no sense to cancel it, or even delay it.
Well, I'm yet to see a convincing argument for how the LHC could destroy the world, or even just mankind. I'd like to think I'm open-minded enough to look critically at any (lucid; some of the above lack lucidity, and therefore are treated harshly) ideas sent to me, so go ahead if you have any. I'll add them to the appendix if they're good, and to the list above if they seem funny/mad enough.
⇐ Back to part three
1 - Source: generic. Special mention goes to http://forums.xkcd.com/viewtopic.php?f=9&t=24344, which cites http://news.bbc.co.uk/1/hi/sci/tech/7468966.stm as making a (probably unintentional) reference (second paragraph, last line).
2 - Source: http://www.youtube.com/watch?v=Lt1Yo610lG0. Please let this be a troll. Please let me have to find another source for this. Please let humanity not be this stupid. Please.
3 - Source: http://www.youtube.com/watch?v=dsDgnmqKeMo
4 - Source: Angels and Demons; the fact that CERN have a webpage (below) dedicated to debunking this indicates that it's been quite an issue.
5 - http://public.web.cern.ch/public/en/Spotlight/SpotlightAandD-en.html
Back in the introduction, I quoted this:
"a single rare high energy cosmic ray may involve a single proton impact with a relatively stationary particle on Earth and send all results safely into space, while collider collisions may involve thousands of protons (or protons to anti-protons) colliding head-on at 99.9999991% of the speed of light in both directions in temperatures lower than space with powerful magnetic fields to help focus all the energy to a single point in space and particles created may be captured by Earth’s gravity."9
and then assumed it had some merit
for the sake of making the point as strongly as possible. While one of its points - that the product of a cosmic ray collision may well have sufficient velocity to escape the gravitational well of a body such as the earth - is mostly true, some parts of this statement need to be taken apart a little. Not to demonstrate how bad the physics
is - only the part that I've already said is good is really needed - but rather to show the lengths that some people will go to simply to create fear
- High-energy cosmic ray collisions are said to be "rare." This is a distortion. While collisions with an energy greater than or equal to 1020 eV are rare at only one per square kilometer per century (http://en.wikipedia.org/wiki/Ultra-high-energy_cosmic_ray#Pierre_Auger_Observatory), cosmic ray collisions with an energy greater than or equal to the energies the LHC will be capable of are far more common. Even if only ultra high energy collisions were to be counted, there are still more than enough to feel secure when you consider the number of square kilometers of matter in the solar system and the number of centuries in its history.
- Collisions at the LHC may involve thousands of particles. True - even an understatement - but irrelevant. The important point is how much energy is involved in a collision, and (in some cases) the area into which it is packed.
- The LHC will perform proton-antiproton collisions. This is incorrect.
- The speed of particles in the LHC is 99.9999991% c. True, but once again, this is just another way of diverting attention from the fact that cosmic ray collisions are much more powerful than this.
- Magnetic fields focusing the energy are significant. Not really. In fact, I mentioned how the degree of focusing is nowhere near sufficient to make the LHC a threat, back in part 2.