gravitaatiolinssiilmiö

Gravitaatiolinssiilmiö, also known as gravitational lensing, is a phenomenon where light from a distant source is bent as it passes by a massive object, such as a galaxy or a cluster of galaxies. This bending of light is a consequence of Einstein's theory of general relativity, which states that mass warps spacetime. When light travels through this warped spacetime, its path is deflected.

The massive object acts like a lens, distorting and magnifying the light from the background source. This can lead to various observable effects, including the appearance of multiple images of the same object, an arc-like distortion, or even a complete ring of light known as an Einstein ring. The degree of bending depends on the mass of the lensing object and its distance from the observer and the background source.

Gravitational lensing is a powerful tool in astronomy. It allows scientists to study distant and faint objects that would otherwise be unobservable. By analyzing the distorted images, astronomers can infer the mass distribution of the lensing object, providing insights into the nature of dark matter, which does not emit light and can only be detected through its gravitational effects. It also helps in measuring cosmological distances and understanding the expansion of the universe. Studying these lensing events can reveal the presence and distribution of matter, including both visible and invisible components, in the universe.