A Search for Rare Decay D0 --> mu+mu - High Energy Physics UPRM

%1.2 Conservation Laws 10current best understanding of such decays uses our knowledge of the weak interactionin perturbation theory calculations together with phenomenological models for the long`distance effects of the color interaction. In the future it is hoped that lattice gauge theorynumerical calculations of the color interaction will achieve sufficient accuracy as to makephenomenological models unnecessary. These do not use perturbation theory to calculatecolor interaction effects.Feynman Diagrams. A Feynman diagram is a representation of the way particlesinteract with one another by the exchange of bosons. They are extremely useful in makingperturbation theory calculations because each representation is associated with formal rulesfor assigning vertex couplings, propagator terms, etc.eeeeFigure 1.3: Feynman diagram for a weak process mediated by a virtual bosonexchange.1.2 Conservation LawsAmong the most significant aids to understanding what takes place in the universe arethe conservation laws, given that they identify those types of interactions that cannot occur.