Continuous symmetries of Lagrangians and exact solutions of discrete equations

@article{Dorodnitsyn2003ContinuousSO,
  title={Continuous symmetries of Lagrangians and exact solutions of discrete equations},
  author={V. A. Dorodnitsyn and Roman Kozlov and Pavel Winternitz},
  journal={Journal of Mathematical Physics},
  year={2003},
  volume={45},
  pages={336-359}
}
One of the difficulties encountered when studying physical theories in discrete space–time is that of describing the underlying continuous symmetries (like Lorentz, or Galilei invariance). One of the ways of addressing this difficulty is to consider point transformations acting simultaneously on difference equations and lattices. In a previous article we have classified ordinary difference schemes invariant under Lie groups of point transformations. The present article is devoted to an… Expand
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