What is a gravitational lens?

Gravity lens is an astronomical phenomenon observed when a massive object, such as a cluster of galaxy or black hole, bends light from a very distant light source such as quasar (young and bright galaxy). This occurs as a result of gravitational deformation of time -off time for the first time described by Albert Einstein in its general theory of relativity. Analogously, it is called a gravitational lens with a conventional lens. Both can bend light, but in this case the mechanism is very different-the mechanism is than the bending of light by means of curved matter, in this case the space-time is curved. Because the light is bent in the gravitational well of the massive object, the apparent location deviates from the actual location. Gravitational lenses can also cause more yeast images to appear in the sky - light is bent around a massive object in both directions, thus producing a picture. "Twin Quasar" Q0597+561, also known as Old Faithful, is the first confirmed object that appeared in the sky twice for GRAvitation lens. Each of the Quasar images is separated in the sky by 6 degrees. Although Fritz Zwicky assumed that Galaxy clusters could act as gravitational lenses in 1937, only in 1979 the effect was confirmed by observation.

There are three types of gravitational lenses. There are strong lenses where you can see easily visible distortion, such as Einstein rings, multiple pictures or arches. It is the most precious gravitational lens. Then there are weak lenses that can only be detected by a large statistical analysis of the Star and Galaxy fields. This form of lens is revealed as a slight stretching towards the center of the lens. The last is microleansing, which is quite rare, but it has been shown to be the most used for astronomical studies. Micropensing is manifested as slight changes in the brightness of the nearby (within our galaxy) caused by star lenses. Distinguishing real microlemensing from star changesIt can be difficult for other reasons (variable stars, novae, etc.).