  The $ee\gamma\gamma +\rlap/E_T$ event observed by the CDF at Fermilab is
naturally explained by dynamically supersymmetry breaking models and suggests
the presence of the light gravitino which can be a warm dark matter. We
consider large scale structure of the universe in the worm dark matter model
and find that the warm dark matter plays almost the same role in the formation
of the large scale structure as a cold dark matter if its mass is about
$0.5$keV. We also study the Ly~$\alpha$ absorption systems which are presumed
to be galaxies at high redshifts and show that the baryon density in the damped
Ly~$\alpha$ absorption systems predicted by the warm dark matter model is quite
consistent with the present observation.
