QCD and Standard Model Effects in Strong, Weak and Electromagnetically Interacting Systems

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All current evidence points to the Standard Model of particle physics as the correct basic theory needed to successfully describe all low-energy phenomena in the universe. In the model, the strong interactions (responsible, for example, for binding neutrons and protons into atomic nuclei) are described using Quantum Chromodynamics (QCD), while the weak and electromagnetic interactions are described using the unified electroweak theory of Glashow, Weinberg and Salam. Understanding the precise implications of the Standard Model, at low energies, for systems which feel the strong interactions (hadrons) turns out to be a difficult task, for technical reasons associated with the strength of the strong interaction at these scales. Such strong interactions complicate technical calculations for all processes involving hadrons. This is true not only for those processes mediated by the strong interaction, but also for those mediated by weak and electromagnetic interactions since the latter are altered in a non-trivial way by the strong force through quantum corrections. In this proposal a number of techniques (including "QCD sum rules", "Chiral Perturbation Theory" and "lattice gauge theory") will be employed to (i) produce quantitative predictions for hadronic processes and properties, and (ii) allow precision determinations of a number of the basic parameters of the Standard Model, which represent the fundamental observables for low-energy phenomena occuring in the universe.