Philip Plait of badastronomy.com has a couple of posts about the LHC, the Large Hadron Collider (there’s also a podcast and here’s a link to a video about the LHC). The LHC is run by the European Organization for Nuclear Research (which is abbreviated CERN for historical reasons; CERN is short for Conseil Européen pour la Recherche Nucléaire ) is the worlds largest particle accelerator and quite possibly the largest science experiment ever (you can find the LHC Homepage here).
The LHC is a ring with a circumference of 27 kilometres; it produces two beams of high enery protons that smash into one another. A number of instruments monitor the collision event and analyze the makeup of the resulting debris as the protons break up into smaller particles. The LHC looks for particles that have been predicted by theory (especially for a particle called the Higgs Boson) but have not been observed yet since smaller particle accelerators cannot mobilize enough energy to create the conditions necessary for those particles to exist (edit: I realize that this badly phrased. Make that “exist under observable conditions”).
The LHC is a much more powerful instrument; in fact it uses so much energy that some people think it will destroy the earth by creating a small black hole that will devour the planet. This is rather unlikely for two reasons.
Contrary to Hollywood lore a black hole is not necessarily some kind of all-devouring cosmic vacuum cleaner; how much damage it can actually do depends on it’s mass. A black hole that is created by the collision of some highly accelerated particles will have about the mass of, well, some higly accelerated particles which is not very much. Even if such a mini black hole would be stable – more likely it would evaporate due to the so called Hawking radiation - I guess it would be too small to interact much with the much more massive planet around it (being a singularity the black hole actually has no size; when somebody talks about the size of a black hole he means the size of it’s event horizon). However that’s just my laymens opinion and the possibility seemed real enough for CERN to study the possible danger – which brings us to the second, rather better reason to dismiss the idea that we are doomed due to the LHC: The people who came up with the theories on how and why black holes form are more or less the same people who tell us that it won’t happen in the LHC. I don’t see why anybody should believe them in the first case but not the second.
If there is no threat then why should we (as in “we laypersons”) care about the thing? Um, that’s a bit hard for me to explain; I read enough books to give the impression that I know something about the matter (unless I accidently talk to an astronomer in which case I give the impresson of being a total twit), but I do not actually understand the stuff. Still…
There a a number of things that seem rather fundamental but cannot, at the moment, be explained very well – like, why is gravity so weak when compared to the other fundamental forces, or why do have some particles have mass in the first place. There are some hypotheses to answer these questions and they propose the exististance of certain particles (like the aforementioned Higgs boson). If the LHC produces these particles it promotes these hypotheses to theories and yet another gap will be closed in our understanding of the universe – well, not my understanding obviously, but on behalf of the laymans part of mankind I’m still proud that somebody gets it. If my choices are to go through life like through some kind of video game (you know, “the story sucks but the graphics are incredible”) or to at least try and make some sense from the world around me, and be it by beating the hell out of some innocent protons– well, you read this blog. I think you can guess how I feel about this.