  Generation, interaction and detection of dark solitons in Bose-Einstein
condensates is considered. In particular, we focus on the dynamics resulting
from phase imprinting and density engineering. The generation of soliton pairs
as well as their interaction is also considered. Finally, motivated by the
recent experimental results of Cornish et al. (Phys. Rev Lett. 85, 1795, 2000),
we analyze the stability of dark solitons under changes of the scattering
length and thereby demonstrate a new way to detect them. Our theoretical and
numerical results compare well with the existing experimental ones and provide
guidance for future experiments.
