  We study the dynamics of a non-integrable system comprising interacting cold
bosons trapped in an optical lattice in one-dimension by means of exact
time-dependent numerical DMRG techniques. Particles are confined by a parabolic
potential, and dipole oscillations are induced by displacing the trap center of
a few lattice sites. Depending on the system parameters this motion can vary
from undamped to overdamped. We study the dipole oscillations as a function of
the lattice displacement, the particle density and the strength of
interparticle interactions. These results explain the recent experiment C.D.
Fertig et al., Phys. Rev. Lett. 94, 120403 (2005).
