Variational approaches for the existence of multiple periodic solutions of differential delay equations.
Variational characterization of equations of motion in bundles of embeddings.
In this paper we study variational principles for a general situation which includes free boundary problems with surface tension. Following [2], our main result concerns a variational principle in a infinite dimensional principal bundle of embeddings of a compact region D in a manifold M having the same dimension as D. By considering arbitrary variations, free boundary problems are included, while variations parallel to the boundary permit to consider fluid motion or flow of Hamiltonian vector fields...
Variational principle for nonlinear Schrödinger equation with high nonlinearity.
Variational principles for differential equations with symmetries and conservation laws. I. Second order scalar equations.
Variations by generalized symmetries of local Noether strong currents equivalent to global canonical Noether currents
We will pose the inverse problem question within the Krupka variational sequence framework. In particular, the interplay of inverse problems with symmetry and invariance properties will be exploited considering that the cohomology class of the variational Lie derivative of an equivalence class of forms, closed in the variational sequence, is trivial. We will focalize on the case of symmetries of globally defined field equations which are only locally variational and prove that variations of local...