N-body simulation

Cosmological simulations are computer simulations that model the dynamic behavior of matter in large spatial areas for periods of billions of years and charge.

Simulations as a method of investigation

For the study of structure formation in the universe, these simulations have been provided decisive evidence. Make the temporal evolution of an assembly of dark matter in a space represents a popular representative is the Millennium Simulation. The previously performed simulations differ mainly in the quality of their resolution and the size of the simulated volume.

Global simulations

Global simulations included the start of the simulation a large number of uniformly distributed dark matter particles and produce in the course of simulation filaments and voids. These are structures that correspond to the largest in the observable universe. The aforementioned Millennium Simulation is one of the global simulations. The purpose of such simulations is to compare the observed structure of the universe with the predictions and thus the parameters of the ΛCDM model (read: Lambda -CDM ) to check. A success does it represent that the ΛCDM parameter to a bottom-up structure formation lead with great similarity to the observation location. In addition, the early emergence of quasars few 100 million years after the Big Bang, which was found in the Sloan Digital Sky Survey, compatible with the simulation result.

Local simulations

Local simulations such as the Aquarius simulation regard the development of a single dark -matter halos. The Aquarius halos are similar to the Milky Way halo in their mass and cosmic neighborhood. This similarity allows statistical predictions about the expected density and velocity distribution of dark matter within the Milky Way. Such predictions are of interest to attempt the direct detection of dark matter, as they meet in principle in the laboratory verifiable statements about the energy and direction of motion of the particles in the range in which move the sun and the earth around the galactic center. They also predict the observable from Earth gamma radiation patterns that could be produced by annihilation of dark matter. In this radiation should be observed by an observer over the whole sky radiation intensity corresponding to the in- line of sight dark -matter amount. This would be a superposition of two patterns. One would be triggered by the halo itself with its approximately ellipsoidal shape and evenly outward decreasing density. In the direction of the galactic center so would be the greatest intensity observed, which would decrease from there in all directions. The lowest intensity thus occurs near the antipode to the center. The second pattern component would be many small-scale brightness increases in the size and the number of predicted subhalos. If this radiation distribution can be observed, would not only the energy of the dark - matter particles known, but also the large-scale distribution in the Milky Way.