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Observations of the CMB communicate that the post Big Bang universe is a homogeneous, isotropic expanding or contracting universe, however this is not the reality of the Universe. It has been further theorized that current structure formation originated from quantum fluctuations. These fluctuations give rise to the measured temperature and density contrast seen in the CMB and large scale structure in a homogeneous isotropic universe \cite{Mo_2009}. Burke et al. (1997) further state that the same fluctuations would have been imprinted on the radiation that we now see as the CMB. The quantum fluctuations resulted from regions whose density was slightly higher than the mean density of the universe. These regions of higher density attracted surrounding matter through gravity. As a result, slightly-denser regions attracted matter towards them and become even denser. Low-density regions on the other hand become even less dense because matter flows away from them. This amplification of quantum fluctuations is referred to as gravitational instability \cite{Mo_2009}. The initial fluctuations were the epicenters of the newly formed clumps of matter mainly made from hydrogen helium and ionized plasma. Thus initial perturbations are the building blocks of atomic nuclei and ionized plasma which combined via recombination to form neutral atoms, there is; however, gas clouds, stars, galaxies, and other astrophysical structures.  There is a significant amount of matter in the universe, which is not directly detectable. Fritz Zwicky observed using the Doppler shift and the virial theorem that the velocity spread within a cluster of galaxies implied that there was more mass than the luminous matter accounted for. Through further experimentation it was later concluded that baryons are set in matter which does not interact with light, but whose effects are observed through gravitational interactions. This non-luminous matter is called dark matter. The nature of dark matter is still unknown; however, dark matter is largely expected to be a collision-less particle \cite{Mo_2009}. Dark matter influences how galaxies form and even their rotation as it is the frame upon which the visible matter is embedded. The distribution of galaxies also depends on the distribution of dark matter in the universe. \citet{Burke_1997} Burke et al. (1997)  state that dark matter may be hot or cold - allowing for different levels of clustering in the Universe. The Hot Dark Dak  Matter (HDM) theory allows for a hierarchy in structure formation. The theory states that large scale structure such as the distribution of galaxies form first due to the presence of hot dark matter. Cold dark matter is theorized to be the seed for galaxy formation. Galaxies are formed from the mergers of stellar material which result in the formation of systems of billions of stars, gas and dust, held together by gravitational attraction. It has been shown that under appropriate conditions, the process of gravitational collapse within a gaseous cloud, the cloud, or some part of it becomes unstable and begins to collapse if it lacks sufficient gaseous pressure support to balance the force of gravity. The cloud is stable for sufficiently small mass (at a given temperature and radius), but once the Jeans mass (a critical mass) is exceeded, the cloud begins a process of runaway contraction until an external unbalanced force can impede the collapse. \citet{Loeb_2010} Loeb et al. (2010)  states that when an object above the Jeans mass collapses, the dark matter forms a halo inside of which the collapsed matter cools, condenses to the center of the dark matter halo, and eventually form stars. Dark matter is weakly interacting and is thus unable to cool. Consequently, the emergent structure of a galaxy becomes one in which a central core that is occupied by stars and cold gas which is enclosed by dark matter. \citet{Loeb_2010} Loeb et al. (2010)  further states that a centrifugal force associated with the rotation of the galaxy’s center prevents the gas from collapsing into the center and forming a black hole. The gas later forms stars and a galaxy is born. Dark matter halos grow in hierarchy in the sense that larger halos are formed through the merging of smaller predecessors. Figure 2 illustrates the formation of a dark matter halo. From this hierarchical model, it can been seen that present formation and evolution of galaxies has its roots in the Big Bang.