Chiral Perturbation Theory
نویسنده
چکیده
After a general introduction to the structure of effective field theories, the main ingredients of chiral perturbation theory are reviewed. Applications include the light quark mass ratios and pion–pion scattering to two–loop accuracy. In the pion–nucleon system, the linear σ model is contrasted with chiral perturbation theory. The heavy–nucleon expansion is used to construct the effective pion–nucleon Lagrangian to third order in the low–energy expansion, with applications to nucleon Compton scattering. Lectures given at the V Workshop on Hadron Physics, Angra dos Reis, RJ, Brazil April 15 20, 1996 To appear in the Proceedings
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