Didactical Experiment
on Gravitational Lensing
DIDACTICAL EXPERIMENT ON GRAVITATIONAL LENSING
The didactical experiments proposed in this contribution and most of the figures are adapted from : Surdej 1990, Refsdal & Surdej 1992, Refsdal & Surdej 1994, Surdej et al 1993, Surdej et al 1996
Because of refractive index variations in the air layers just above the ground, atmospheric lensing may significantly deform our view of distant Earth-objects. Similarly, gravitational lensing perturbs our view of the distant Universe and affects our physical understanding of various classes of extragalactic objects. After recalling the basic principles underlying the formation of atmospheric and gravitationally lensed mirages, we describe a simple optical lens experiment which accounts for all types of image configurations observed among presently known gravitational lens systems...
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During the elaboration of his theory of General Relativity, Einstein (1915) predicted that a massive object curves the spacetime in its vicinity and that any particle, massive or not (cf. the photons), will move along the geodesics of this curved space...
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THE OPTICAL GRAVITATIONAL LENS EXPERIMENT
For didactical purposes, it is very useful to construct and use optical lenses that mimic the deflection of light rays...
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The Optical Gravitational Lens Experiment
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Expérience de la lentille gravitationnelle
The Optical Gravitational Lens Experiment
Gravitational Lensing by a Wine Glass (The Universe in the Classroom)
- The formation of multiple images of a distant quasar by the gravitational lensing effects of a foreground galaxy may be very simply, and faithfully, accounted for by the wine glass experiment.
OTHER EXAMPLES OF CAUSTICS AND MULTIPLE IMAGING
1. Gravitational lensing and the wine glass experiment 1. Gravitational lensing and the wine glass experiment
The formation of multiple images of a distant quasar by the gravitational lensing effects of a foreground galaxy may be very simply, and faithfully, accounted for by the wine glass experiment described below.
2. Multiple imaging as seen by whales and sharks
The interface between the air and the water in a swimming pool, on a lake, on a sea, etc., is wavy and as a result, the propagation of light rays from a distant source (cf. the sun, the moon, etc.) gets distorted after entering water...
3. Multiple imaging at the House of Mirrors
Finally, it is fun to observe multiple images of human beings at the House of Mirrors, available during most of the big city fairs. Such mirages are produced by curved mirrors which distort light rays emitted from the surroundings.
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Les lentilles gravitationnelles et l'expèrience du verre de vin
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Gravitational lens simulations
Simulations for axially symetric deflector
Gravitational lens simulations
Simulations for axially symetric deflector