ABSTRACT
Gauge symmetries in the theory of gravity can be naturally analysed within the Hamiltonian formalism for constrained dynamical systems. The existence of gauge symmetries is observed by the presence of arbitrary multipliers (or, equivalently, FC constraints) in the total Hamiltonian. The old question about the relation between the nature of constraints and the form of gauge generators has been resolved by Castellani, who developed an algorithm for constructing all the canonical gauge generators (Castellani 1982). The method demands knowledge of the Poisson bracket algebra of FC constraints, and gives the gauge generators acting on both physical and unphysical phase-space variables.
