Norimasa Sugiura

How Do Nonlinear Voids Affect Light Propagation ? (1999)

Sugiura, Norimasa, Nakao, Ken-ichi, Ida, Daisuke, Sakai, Nobuyuki, Ishihara, Hideki

Propagation of light in a clumpy universe is examined. As an inhomogeneous matter distribution, we take a spherical void surrounded by a dust shell where the ``lost mass'' in the void is compensated...

Distance-redshift relation in an isotropic inhomogeneous universe II: Spherically symmetric dust-shell universe (1999)

Sugiura, Norimasa, Nakao, Ken-ichi, Harada, Tomohiro

The relation between the angular diameter distance and redshift in a spherically symmetric dust-shell universe is studied. We have discovered that the relation agrees with that of an appropriate...

Distance-redshift relation in an isotropic inhomogeneous universe: Spherically symmertic dust-shell universe (1998)

Sugiura, Norimasa, Nakao, Ken-ichi, Harada, Tomohiro

The relation between angular diameter distance and redshift in a spherically symmetric dust-shell universe is studied. This model has large inhomogeneities of matter distribution on small scales. We...

Friedmann Limit of a point mass universe (is not Friedmann):Gravinational Lens Effect (1998)

Sugiura, Norimasa

We study the distance-redshift relation in a universe filled with point particles, and discuss what the universe looks like when we make the number of particles N very large, while fixing the...

Effects of the UV background radiation on galaxy formation (1998)

Nagashima, Masahiro, Gouda, Naoteru, Sugiura, Norimasa

We investigate the effects of the UV background radiation on galaxy formation by using the semi-analytic model including the photoionization process. The semi-analytic model is based on Cole et al....