Elimination of the auxiliary fields in the antifield formalism

The problem of the elimination of the auxiliary fields in the path integral quantization of gauge theories is investigated in the context of the antifield formalism. It is shown that gauge fixing fermions can be found such that: (i) the auxiliary fields remain auxiliary after gauge fixing; and (ii) the gauge fixed actions obtained by eliminating the auxiliary fields before or after writing down the path integral coincide. The contribution of the auxiliary fields to the integration measure is also discussed. These results are applied (i) to the problem of the equivalence between the lagrangian and hamiltonian path integral formulations; and (ii) to the problem of the elimination of the second class constraints in the hamiltonian formalism. (orig.)