In this paper we extend the variational calculus to fibered-fibered manifolds. Fibered-fibered manifolds are surjective fibered submersions π:Y → X between fibered manifolds. For natural numbers s ≥ r ≤ q with r ≥ 1 we define (r,s,q)th order Lagrangians on fibered-fibered manifolds π:Y → X as base-preserving morphisms . Then similarly to the fibered manifold case we define critical fibered sections of Y. Setting p=max(q,s) we prove that there exists a canonical “Euler” morphism of λ satisfying a decomposition property similar to the one in the fibered manifold case, and we deduce that critical fibered sections σ are exactly the solutions of the “Euler-Lagrange” equations . Next we study the naturality of the “Euler” morphism. We prove that any natural operator of the “Euler” morphism type is c(λ), c ∈ ℝ, provided dim X ≥ 2.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-1-1, author = {W. M. Mikulski}, title = {On the variational calculus in fibered-fibered manifolds}, journal = {Annales Polonici Mathematici}, volume = {89}, year = {2006}, pages = {1-12}, zbl = {1106.58003}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-1-1} }
W. M. Mikulski. On the variational calculus in fibered-fibered manifolds. Annales Polonici Mathematici, Tome 89 (2006) pp. 1-12. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-1-1/