What is Dark Matter? And how does it look like?
About 80 % of the matter in the universe consists of a substance that no one has ever seen before, dark image matter. While the baryonic matter known to us contributes only about five percent of the energy density, dark matter accounts for almost 27 percent. But what really lies behind Dark Matter is what scientists are trying to find out with the most diverse methods.
In the 1930s, the first real evidence of Dark Matter was found. The Swiss astronomer Fritz Zwicky examined the movement of galaxies in the Coma galaxy cluster and discovered that they were much too fast when visible matter could have held the stars, dust and gas together with their gravity.
Zwicky explained it this way: "This phenomenon could only be explained by the assumption that there is an enormous amount of invisible mass that provides cohesion among all the celestial objects.
But what exactly does this matter consist of?
It is therefore clear that this dark matter only appears to be made up of its gravitational interaction with normal matter known to us, which otherwise remains invisible to us.
Dark matter consists of the so-called MACHOs (massive astrophysical compact halo objects), which include, for example, brown dwarfs or black holes, so the sole explanation is out of the question. So it must really be a completely new kind of matter.
Theoretical physicists have already proposed some hypothetical particles that could make up dark matter, such as the lightest supersymmetric particle, the neutralino. The neutralino is a possible candidate for the so-called WIMPs (weakly interacting massive particles). Many experimental physicists are already looking for this particle. They are pursuing three different approaches:
Experiments in the air or in space
It is assumed that two WIMPs meeting each other cancel each other out and release the released energy in the form of a photon. In order to detect these photons, one goes to high altitudes, because in the lower layers of the atmosphere the particles react with air molecules, are absorbed and cause a particle shower, which makes the measurement impossible.
In order to be able to detect the interaction of a WIMP with an ordinary particle of matter in a detector, one has to protect oneself as best as possible from cosmic radiation and other sources of interference. Therefore, laboratories are usually built in former mines or under mountains. Because the interaction they are looking for occurs very rarely, the researchers need a lot of detector material and long measurement times.
In large accelerators, attempts are being made to create dark matter artificially. This requires a great deal of energy. In addition, sophisticated algorithms are needed to filter out such processes, in which WIMPs are created, from the many results of a particle collision. A typical indication would be, for example, a lack of energy, since the WIMPs are invisible to the detector when they leave it, but at the same time carry a lot of kinetic energy with them.
If you want to know more about Dark Matter go on darkmatterlabs.org
Or visit the site energy.gov