A consistent approach to approximate Lie symmetries of differential equations

  title={A consistent approach to approximate Lie symmetries of differential equations},
  author={Rosa Di Salvo and Matteo Gorgone and Francesco Oliveri},
  journal={Nonlinear Dynamics},
Lie theory of continuous transformations provides a unified and powerful approach for handling differential equations. Unfortunately, any small perturbation of an equation usually destroys some important symmetries, and this reduces the applicability of Lie group methods to differential equations arising in concrete applications. On the other hand, differential equations containing small terms are commonly and successfully investigated by means of perturbative techniques. Therefore, it is… 
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