  The scalar normal modes of higher dimensional gravitating kink solutions are
derived. By perturbing to second order the gravity and matter parts of the
action in the background of a five-dimensional kink, the effective Lagrangian
of the scalar fluctuations is derived and diagonalized in terms of a single
degree of freedom which invariant under infinitesimal diffeomorphisms. The
spectrum of the normal modes is discussed and applied to the analysis of short
distance corrections to Newton law.
