Classical field theories of first order and lagrangian submanifolds of   premultisymplectic manifolds
  A description of classical field theories of first order in terms of Lagrangian submanifolds of premultisymplectic manifolds is presented. For this purpose, a Tulczyjew's triple associated with a fibration is discussed. The triple is adapted to the extended Hamiltonian formalism. Using this triple, we prove that Euler-Lagrange and Hamilton-De Donder-Weyl equations are the local equations defining Lagrangian submanifolds of a premultisymplectic manifold. 
C\'edric M. Campos, Elisa Guzm\'an, Juan Carlos Marrero
math.DG math-ph math.MP