CP Violation

CP violation has become one of the central problems of subatomic-particle physics, with $200-million "B factories" now in operation both in Japan and the U.S. for its study. It is arguably the only known subatomic effect for which no clear explanation exists in the "Standard Model" of particles and their interactions. A subtle difference between the properties of particles and of antiparticles, CP violation has been postulated (by Russian physicist Andrei Sakharov) to have been responsible for the development, shortly after the Big Bang, of the slight excess of matter over antimatter from which the entire material universe has since evolved. To date, CP violation has been convincingly established in decays of the neutral K and B mesons. More than thirty-five years of experimental effort in its study have succeeded in determining only two parameters of the theory -- parameters that explain no other known effect. Should CP violation be observed in decays of charmed particles or hyperons, there is reason to hope for a breakthrough in its understanding.