| In this thesis I use the publicly available smooth particle hydrodynamics (SPH) code GADGET-2 to investigate and recreate the phenomenon of two merging galaxy clusters, as currently seen in the hot X-ray cluster 1E 0657-56 (the "bullet cluster"). In this scenario, the stellar and dark matter components of the galaxies pass through the collision without experiencing strong stopping forces, but the intra-cluster gas is significantly slowed by ram pressure. This leads to a spatial separation between the galaxies and the intra-cluster gas, which provides a testing ground for gravitational theories. Weak gravitational lensing in the cluster has been used to show that the majority of the mass is concentrated near the galaxies and not in the intra-cluster gas, the dominant baryonic component of mass, leading some to hail this as proof of the existence of non-baryonic dark matter. |
