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Register a new userConstraints on Four-Point Couplings in Low-Energy Meson Interactions
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We investigate from first principles the introduction of isospin-1 vector and axial-vector fields into the nonlinear sigma model. Chiral symmetry is nonlinearly realised and spin-1 fields are assumed to transform homogeneously under chiral rotations. By requiring the Hamiltonian of the theory to be bounded from below we find inequalities relating three- and four-point meson couplings. This leads to a low-energy phenomenological Lagrangian for the nonanomalous sector of $pirho a_1$ strong interactions.
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