The Lagrangian Formalism

摘要: We shall hereafter introduce the global Lagrangian formalism for field theories (which applies in particular to Mechanics). In Section 2, most important algebraic Lemmas are presented an abstract and general form they then applied Variational Calculus obtain relevant quantities a Field Theory. The approach based on Poincare-Cartan is also briefly discussed. Then symmetries conserved defined obtained by Nother theorem. Finally some useful generalizations of and, consequently, theorem presented.