| Popis: |
A general method is stated for obtaining functionals associated with the scattering operators. Four conditions are required on the functional to determine the quantities involved in it, which are related to the operator and its perturbative series. No asymptotic condition is specified on the trial functions. The method is applied to the $T$ matrix leading to a family of functionals in which the lowest order is Schwinger's functional. The applications to the $S$ matrix and other operators are also discussed. |
