>>455 Smashes atoms together at ultra-high speeds to try to recreate the aftermath of the Big Bang.
Actually, it smashes protons (i.e. hadrons) together at high speed, liberating an energy of max 14TeV(?) during the collision, then collects data about the "debris" created in the process. 14TeV is not a "large" energy, physically speaking so don't expect Unification Scale phenomena. Still, with some luck one might prove the existence of the Higgs boson, find evidence of "supersymmetry" (even if there are people starting to doubt that it exists) and find evidence of events that cannot fit into the currently accepted "Standard Model" theoretical framework, making life interesting. Don't expect fleeting black holes to pop out there though - that's extremely unlikely to happen (i.e. only possibly if assumptions about gravity likely to be false turn out to be actually true).