The importance of flavor physics

The recent measurements at B-factories confirming a non-zero value of sin 2 0 show that CP violation is not restricted to the kaon system. This discovery is the latest of many that support the current Standard Model of particle physics. However, particle physicists believe that the Standard Model is not a complete explanation of nature. I discuss the questions that particle physicists are seeking to answer and why precision measurements in flavor physics are one way to search for the physics beyond the Standard Model. I begin with a brief overview of the CKM matrix and its parameters. I will explain why improving the precision of measurements of the CKM matrix elements is important, and why better measurements and more measurements of CP violation are needed to help probe beyond the Standard Model. Some possible extensions of the Standard Model are described. I will discuss some of the experimental issues and then make the case for the need for a broad program of research in heavy flavor physics, comparing and contrasting different experimental techniques. The measurement of sin 2 beta is discussed in some detail to give the reader a feel for some of the experimental complications that need to be considered.