Gravitational Lenses
نویسنده
چکیده
Gravitational lenses are becoming a precious mean of probing the matter distribution in the Universe. From the search of matter in the Galactic halo to the study of the large-scale structures of the Universe, the gravitational lens effects offer a unique alternative to light surveys and are now widely used. This evolution is due in particular to the use of new observation devices, such as the wide field CCD cameras. The aim of this course is to study the effects of gravitational lenses in those different astrophysical contexts. These notes are voluntarily focused on the fundamental mechanisms and the basic concepts that are useful to describe these effects. The observational consequences will be presented in more details in these proceedings by Y. Mellier (see also his review paper 1998). Related textbooks are,
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