We obtain expressions for the vacuum expectations of the energy-momentum
tensor of the scalar field with an arbitrary coupling to the curvature in an
N-dimensional homogeneous isotropic space for the vacuum determined by
diagonalization of the Hamiltonian. We generalize the n-wave procedure to
N-dimensional homogeneous isotropic space-time. Using the dimensional
regularization, we investigate the geometric structure of the terms subtracted
from the vacuum energy-momentum tensor in accordance with the n-wave procedure.
We show that the geometric structures of the first three subtractions in the
n-wave procedure and in the effective action method coincide. We show that all
the subtractions in the n-wave procedure in a four- and five-dimensional
homogeneous isotropic spaces correspond to a renormalization of the coupling
constants of the bare gravitational Lagrangian.Comment: LATEX, 20 pages, no figur