  The response of a massive body to gravitational waves is described on the
microscopic level. The results shed a new light on the commonly used oscillator
model. It is shown that apart from the non-resonant tidal motion the energy
transfer from a gravitational wave to an electromagnetically coupled body is in
general restricted to the surface, whereas gravitational coupling gives rise to
bulk excitation of quadrupole modes, but several orders of magnitude smaller.
These results do not contradict standard theory, rather present a different
viewpoint. A microscopic detector making use of the effect is suggested.
