User:Søren Bertil F. Dorch/Proposed/Gravitational lensing
Dr. Jean-Paul Kneib accepted the invitation on 4 October 2007 (self-imposed deadline: 1 February 2008).
Gravitational Lensing is the phenomenon of light deflection by massive bodies in the Universe. Indeed, following Einstein's general relativity, a massive object in the Universe locally deforms spacetime, hence a light ray (following a geodesic) will be deflected in a similar way as an optical lens. Although the deflection of light is expected in the classical Newtonian theory, the deflection is twice larger under general relativity. For this reason, the gravitational lensing of the Sun was one of the first tests of general relativity theory. The first measure of the Sun deflection was recorded by Sir Arthur Eddington during the solar eclipse of 1919.