MSc defence by Kristine Simone Nielsen

Title: Expanding the Physics of Dark Matter - Exploring a new way to explain the acceleration of the Universe.

Abstract: In this thesis we explore if it is possible to describe the acceleration of the Universe, through some effects of the movements of dark matter particles in dark matter halos. This model is based on the velocity dispersion of the halos, that is created due to the individual motions of the dark matter particles inside the halo. Through these motions of dark matter particles, an effect might arise that mimics the effects of $\Lambda$, which should enable us to substitute the cosmological constant in the Benchmark model. Using numerical simulations, we have tested possible variations of the model, where we find that our model provides a reasonable fit to the Benchmark model. This means that it is possible that our model is able to describe the acceleration of the Universe without including the cosmological constant.