| Back | Up | Map | Glossary | Information |
Numerical cosmologists have explored various mixtures of cold and hot dark matter, which cluster in different ways. Hot dark matter forms large coherent filaments, whereas cold dark matter produces hierarchically clustered objects--like the real universe. One class of calculations performed on pure dark matter models are scale-free. Scale-free studies, while not true cosmological models, provide a convenient abstraction of realistic power spectra in two simple parameters which are easy to characterize and explore.
In such simulations, numerical cosmologists trace the gravitational interactions of "mass clouds" of dark matter particles within grid boxes. This approach, called a particle-mesh algorithm, allows the cosmologists to calculate the force exerted on groups of mass clouds by other mass clouds. As the clouds move in response to each other's gravity, the density distribution changes too, which in turn alters the movements of the clouds.
Featured below are three types of scale-free, pure dark matter simulations, each containing greater complexity.
Return to Cooking the Cosmos
Up to Cosmic Code Building