Mr. Tea
Let's Talk About Ceps
The LHC is a particle accelerator located on the France/Switzerland border; it has been dubbed the largest, most expensive, most powerful experiment ever attempted, certainly dwarfing all particle colliders ever built before, both in terms of size and power.
I think it's quite telling that they haven't done their homework very thoroughly: the LHC is exactly the same size as the LEP collider that was built at CERN in the '80s, since it's been constructed in the old LEP tunnel.
On the subject of comparisons to existing colliders, experts in the field say that the production of mini black holes is theoretically more likely at RHIC (the Relativistic Heavy Ion Collider on Long Island) - which has been running for some years already without so far destroying the earth - than at the LHC.
Something I'm surprised physicists don't mention more often in their own defence is that ultra-high energy cosmic rays smash into the earth's atmosphere all the time, causing collisions with energies ten or a hundred times higher than those that will occur at the LHC, and that if this was likely to bring about the apocalypse it would presumably have done so by now.