A NEW EFFICIENT METHOD FOR CALCULATING PERTURBATIVE ENERGIES USING FUNCTIONS WHICH ARE NOT SQUARE INTEGRABLE - REGULARIZATION AND JUSTIFICATION - COMMENT

The method recently proposed by Skala and Cizek for calculating pertur bation energies in a strict sense is ambiguous because it is expressed as a ratio of two quantities which are separately divergent. Even tho ugh this ratio comes out finite and gives the correct perturbation ene rgies, the calculational process must be regularized to be justified. We examine one possible method of regularization and show that the pro posed method gives traditional quantum mechanical results.