GRAVITATIONAL LENSING IN A UNIVERSE MODEL WITH REALISTIC MASS-DISTRIBUTION

We study the light propagation in an inhomogeneous universe using Monte Carlo methods. The model of matter distribution includes galaxies of different masses and radii and position correlations. Different cosmological models are taken into account. The light beams are allowed to scatter several times between a source and the observer due to gravitational deflection caused by galaxies at different redshifts. The effects of microlensing are included in further approximation. We show that correlations in galaxy positions increase the probability of observing a distant source highly amplified by foreground gravitational lenses.