Quantum field theory with a chiral lagrangian and physics of low-energy mesons

The quantum chiral theory is reviewed which combines the tool of dispersion relations with the method of perturbation theory in terms of the quantum field theory with chiral dynamic symmetry. The theory discussed makes it possible to obtain low-energy amplitude expansions for different hadron processes without introducing arbitrary (phenomenological) parameters. A hypothesis on dynamic symmetry of strong interactions is detailed, and a lagrangian of interactions with such symmetry is derived. Some physical consequences are drawn in terms of the singleloop approximation for ππ-scattering, electromagnetic (Compton effect) and weak (charged pion decays) interactions