  If a bosonic partner of a right-handed neutrino dominates the early universe
sufficiently before its decay, important ingredients in the present universe
are related to physics of the right-handed neutrino sector. In particular, we
find that the ratio of the baryon to the dark-matter densities is given only by
low-energy parameters such as a neutrino mass and a gravitino mass if the
reheating temperature of inflation is much higher than $10^{12}$ GeV. Here, the
gravitino is assumed to be the lightest supersymmetric particle and the
dominant component of the dark matter. The observed ratio,
$\Omega_{B}/\Omega_{DM} \simeq 0.21\pm 0.04$, suggests the mass of the
gravitino to be in the range of $\cal O$(10) MeV provided the CP violating
phase is of the order 1.
