Derivation of the Effective Chiral Lagrangian for Pseudoscalar Mesons from QCD
نویسندگان
چکیده
The study of low energy hadron physics in QCD is a long standing difficult problem due to its nonperturbative nature. For low lying pseudoscalar mesons, a widely used approach is the theory of effective chiral Lagrangian based on the consideration of the global symmetry of the system and the momentum expansion without dealing with the nonperturbative dynamics of QCD [1] [2]. In the chiral Lagrangian approach, the coefficients in the Lagrangian are all unknown phenomenological parameters which should be determined by experimental inputs. The number of the unknown parameters increases rapidly with the increase of the precision in
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