Constrained theories are of great interest in theoretical physics, since all known theories of fundamental interactions present gauge freedom, which is a type of singular feature of the theory and implies that the theory is constrained. On the other hand, since the quantum theory is commonly constructed on a Hamiltonian structure, the canonical quantization process is the most suitable if the Hamiltonian formulation of the classical theory is available. Thus, the necessity to obtain the Poisson Brackets (PB) of the canonical variables in the theory to be quantized arises. In the present work we study the Faddeev and Jackiw proposal, reviewed by Barcelos-Neto and Wotzasek, to obtain the PB in singular theories by means of an approach employing the geometric elements of the Hamiltonian theory themselves. The process was built specifically for matter point mechanics and subsequently was implemented in a sequence of examples, obtaining the fundamental PB in each of them, thus preparing the ground for quantization.
Keywords
Classical mechanics; symplectic form; constrained systems