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Light Propagation in Inhomogeneous Universes II. Cosmological Parameter Survey

Premana Premadi·Hugo Martel·Richard Matzner·Toshifume Futamase
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Abstract

Using a multiple-lens plane algorithm, we study light propagation in inhomogeneous universes, for 43 different COBE-normalized Cold Dark Matter models, with various values of the density parameter Omega_0, cosmological constant lambda_0, Hubble constant H_0, and rms density fluctuation sigma_8. This is the largest cosmological parameter survey ever done in this field. We performed a total of 3,798 experiments, each experiment consisting of propagating a square beam of angular size 21.9'' x 21.9'' composed of 116,281 light rays from the observer up to redshift z=3. These experiments provide statistics of the magnification, shear, and multiple imaging of distant sources. The results of these experiments can be compared with observations, and eventually help constraining the possible values of the cosmological parameters. Additionally, they provide insight into the gravitational lensing process and its complex relationship with the various cosmological parameters.

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Premana Premadi, Hugo Martel, Richard Matzner, Toshifume Futamase. 2001-01-21. Light Propagation in Inhomogeneous Universes II. Cosmological Parameter Survey. https://doi.org/10.1086/321776

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