Leptonic and Semileptonic D Decays and New Physics

Particle Physics is the study of the fundamental particles of the universe, or, in other words, particle Physics is the study of really, really small stuff. As of right now, we know of twelve fundamental particles: six quarks and six leptons. This is known as the Standard Model in the Physics world. There are currently hundreds of identified particles made from combinations of these twelve fundamental particles and scientists are still finding more. Quarks are the fundamental building blocks of nature. They combine to form larger particles, such as protons and neutrons.You are probably familiar with the electron; the muon and the tau are the heavier, less well known cousins to the electron. The muon and tau are rarer than the electron, have the same negative charge that the electron has.There is one neutrino for each of the electron, the muon, and the tau. Leptons are much lighter than the quarks, in fact the neutrinos are so light that there is debate whether they have mass at all! Now we know the building blocks of matter, but we must also ask: What holds it together? All forces are due to the underlying interactions of the particles.