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Physics in Action
Oct 6, 2004
B-factories score direct hit on CP violation
The universe that we observe today is dominated by matter. However, we do not know of any mechanism by which a matter particle can be created without an antimatter partner. So what breaks the symmetry between matter and antimatter? The answer to this question is thought to lie in the violation of charge-parity (CP) symmetry. The weak interaction, as described by the Standard Model of particle physics, does not conserve CP symmetry: in other words, the results of an experiment that probes the weak interaction will change when particles are replaced with their antiparticles and all three spatial co-ordinates are reversed.