The Standard Model hangs on discovery of the mysterious Higgs boson.
Image courtesy of Fermilab.
Particle accelerators such as the Tevatron and the LHC were built to probe the Standard Model of particle physics. The Standard Model (see above) describes three of the four forces of nature: Electromagnetism, and the Strong and Weak forces. Gravity is left out, as is the mechanism by which objects in the universe acquire mass. This latter mystery is where the Higgs boson comes in. Although physicists know how most particles interact in order to give rise to such properties as radioactivity and light emission, no one knows where the property of mass comes from. In 1960, Peter Higgs came up with the idea of a field that permeates all of space, much like the electromagnetic field; but instead of gathering electromagnetic energy from photons in this field, particles traveling through the Higgs field would be granted mass by Higgs bosons.
At the moment, Fermilab is denying that any such discovery has been made. On July 12, scientists posted the following via the FermilabToday Twitter account: "Let's settle this: the rumors spread by one fame-seeking blogger are just rumors. That's it." Ouch. Keep in mind, however, that this is the same group who announced they had a 50% chance of detecting the Higgs particle this year. We'll just have to wait and see.