Astrophysical Applications of Gravitational Lensing

Gravitational lenses offer the best, and sometimes the only, means of tackling key problems in many fields of astrophysics and cosmology. According to Einstein''s theory, the curvature of light-rays increases with mass; gravitational lenses can be used to map the distribution of mass in a Universe in which virtually all matter is dark matter of an unknown nature. Gravitational lensing has signific...