CERN's Large Hadron Collider is scheduled to begin operation this summer. When fully operational, it will smash protons together at energies that were present just after the big bang. The collisions will occur 600 million times every second, producing a spray of subatomic debris. Physicists hope somewhere in that haystack they will find the following needles:
The Higgs Particle (Named after physicist Peter Higgs)
What does it do? It gives things mass. The Higgs particle would be a companion to an (also hypothetical) Higgs "field." The field would pervade the universe and act like cosmic molasses, making everything hard to move. That's what we call mass.
Why do we need it? Without the Higgs particle, electrons would have no mass and atoms wouldn't stick together. We would fall apart into piles of atomic nuclei.
Likelihood it's real? High. Physicists generally agree the Higgs or something like it must exist.
How hard would it be to find? It depends on the Higgs particle's characteristics. The Higgs doesn't live long and quickly decays into other particles. Depending on what those are, physicists might be able to pick out Higgs fingerprints quickly, or it could take years of sifting through data.
What is it? Dark Matter is the name given to the mysterious invisible material that seems to hang around galaxies. Estimates are that 20 percent of the stuff in the universe is dark matter. Astronomers call it dark because they can't see it.
If it's invisible, how do you find it? You don't — or at least not directly. If the LHC makes dark matter particles, they will escape without leaving a trace. But physicists are prepared. They should be able to notice its absence.
Likelihood it will appear? Unclear. Many physicists believe that dark matter particles are part of a whole family of new particles. This theory, known as Supersymmetry (SUSY), says that every known particle has a heavier sibling. The problem is, no one has ever observed one of these hefty partners.
Miniature Black Holes
What are they? Teeny tiny, superdense objects.
Yikes, should I be worried? No, they wouldn't live long. Estimates are a thousandth of a trillionth of a trillionth of a second.
How do you detect one? A miniature black hole would collapse and can create all particle types that exist.
Likelihood mini black holes really will appear? Physicists agree they're a long shot. Miniature black holes appear in some theories that say there are extra, tiny dimensions to space-time. And while the idea of extra dimensions is popular — as part of something called string theory for instance — they don't necessarily allow for mini black holes.