The Influence of Dark Matter on Galactic Structure and Cosmic Evolution

This paper examines the crucial role dark matter plays in both the development of galactic structure and the timeline of cosmic evolution. First, it investigates how the masses of dark matter halos regulate the growth rate of supermassive black holes (SMBHs), thereby controlling galactic structure. The halo depth determines gas inflow rates and cooling efficiency, which decides the rate at which SMBHs accrete matter. As feedback from SMBHs in turn influences star formation rates and the stability of galactical structures, this paper discusses the specific outcomes each type of dark matter halo imposes on galactic structure. Then, the paper explores how different dark matter models, such as hot, cold, warm, and lambda cold dark matter, determine whether primordial density fluctuations survived or were erased during early phases of the universes history. The transfer function of each model is identified, then a graphic comparing each respective matter power spectrum, a cosmological parameter derived from the transfer function, is demonstrated. Finally, the paper would compare observational results from SDSS with the scenarios each matter power spectrum predicted and determine the most accurate dark matter model.