Approximate symmetries in dynamical systems
نویسندگان
چکیده
The knowledge of exact symmetries of a diierential problem allows to reduce it, and sometimes to completely solve it; it also allows to obtain exact solutions. If we are looking for approximate rather than exact solutions, then approximate symmetries are as good as exact ones; moreover, they can be determined perturbatively. In this paper we introduce and study approximate symmetries, together with some applications to the determination of approximate solutions of dynamical systems.
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