The Cosmic Evidence for Dark Matter From Computer Simulations

Cosmologists used computer simulations to model how particles would act under the force of gravity as the universe expanded and cooled. The first particles people tested in these simulations are called neutrinos. Hot dark matter tends to form very, very big clumps which then break into smaller clumps making things like galaxies. In contrast, cold moving dark matter particles will be slow movingDark Matter particles form small things first and then those small things merge making bigger and bigger and bigger things. That gives us a pretty good reason to think there is a lot of cold dark matter in our universe.