Variational symmetries and pluri-Lagrangian structures for integrable hierarchies of PDEs

@article{Petrera2019VariationalSA,
  title={Variational symmetries and pluri-Lagrangian structures for integrable hierarchies of PDEs},
  author={Matteo Petrera and Mats Vermeeren},
  journal={European Journal of Mathematics},
  year={2019}
}
We investigate the relation between pluri-Lagrangian hierarchies of 2-dimensional partial differential equations and their variational symmetries. The aim is to generalize to the case of partial differential equations the recent findings in Petrera and Suris (Nonlinear Math. Phys. 24(suppl. 1):121–145, 2017) for ordinary differential equations. We consider hierarchies of 2-dimensional Lagrangian PDEs (many of which have a natural $$(1\,{+}\,1)$$ ( 1 + 1 ) -dimensional space-time… 

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