On a Functional Geometric Framework for Classical Field Theory
We present a description of a rigorous geometric and functional framework for the kinematics of classical field theory where field configurations are understood as values of sections of a smooth fiber bundle and observables are given by an appropriate class of functionals over this space. An infinite dimensional smooth manifold structure is introduced in this space through a lift of the differential geometric objects on the fiber bundle to the space of smooth sections of the latter, making possible to perform the differential calculus of such functionals. This lift is canonically determined from a choice of partial covariant derivative on the vertical bundle of the fiber bundle along itself and only depends on the point values of each section.