Researchers have discovered a large number of “lenses” of dark matter. They may reflect distant parts of the universe, but scientists need to learn how to decode these distorted images.
According to a study published in the journal Science, the gravitational fields of dark matter can create “effective lenses” that can help astronomers observe parts of the universe that were previously inaccessible. An observer for whom the gravitational lens obscures the light source will observe its multiplied curved images – their shape, number and position will be determined not only by the position of the background source relative to the lens and the observer, but also by the mass distribution in the lens itself.
Scientists led by Massimo Meneghetti, a cosmologist at the Bologna Observatory of Astrophysics and Space Sciences, estimated the number of small-scale gravitational lensing events in galaxy clusters based on observations and then compared it with the result of computer simulations. It turned out that simulations predict a lot more of these lenses.
Sufficient lenses of dark matter will help astronomers study the universe more fully. Lens phenomena occur when a gravitationally influencing object, perhaps a group of dark matter, aligns with a source of background light, for example, in a distant galaxy. As light travels through an object’s gravitational field, it can become significantly brighter.
However, he noted that lenses tend to distort images of background sources, which means scientists must come up with a way to reverse-engineer the original shapes of objects from the deformed versions that the lens provides.