Beyond the Standard Model


		Beyond the Standard Model Although the Standard Model answers many of the questions about the structure and stability of matter, it is an incomplete theory because it can't fully explain the nature of the world. Why are there three generations of quarks and leptons? Are quarks and leptons really fundamental, or are they in turn made up of even more fundamental particles? Particle experiments suggest almost equal symmetry between matter and antimatter. Yet our very existence depends on our Universe being mostly matter. How do we explain this? How will gravity fit into the Standard Model? There appears to be more matter in the Universe than we can observe in stars. What is this invisible dark matter? Why can't the Standard Model predict a particle's mass? Questions such as these drive particle physicists to build and operate newer and better accelerators, so that higher-energy collisions can provide clues to the answers.