# Symmetry actions and brackets for adjoint-symmetries. II: Physical examples

@article{Anco2022SymmetryAA, title={Symmetry actions and brackets for adjoint-symmetries. II: Physical examples}, author={Stephen C. Anco}, journal={European Journal of Applied Mathematics}, year={2022} }

Symmetries and adjoint-symmetries are two fundamental (coordinate-free) structures of PDE systems. Recent work has developed several new algebraic aspects of adjoint-symmetries: three fundamental actions of symmetries on adjoint-symmetries; a Lie bracket on the set of adjoint-symmetries given by the range of a symmetry action; a generalised Noether (pre-symplectic) operator constructed from any non-variational adjoint-symmetry. These results are illustrated here by considering five examples…

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