  For a model of atoms and molecules made from static nuclei and
non-relativistic electrons coupled to the quantized radiation field (the
standard model of non-relativistic QED), we prove a Mourre estimate and a
limiting absorption principle in a neighborhood of the ground state energy. As
corollaries we derive local decay estimates for the photon dynamics, and we
prove absence of (excited) eigenvalues and absolute continuity of the energy
spectrum near the ground state energy, a region of the spectrum not understood
in previous investigations. The conjugate operator in our Mourre estimate is
the second quantized generator of dilatations on Fock space.
