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\subsection{Galaxy Evolution: from the Big Bang to present day}  The Big Bang is the birth of our Universe. The early state of the Universe was hot and dense. In this era, matter was coupled to radiation, according to early models of structure formation which assumed adiabatic initial conditions. The Universe expanded and temperature decreased, this occurred approximately 380 000 years after the Big Bang at a redshift of z = 1100 and is depicted in Figure 1. It is also theorized that matter and radiation became decoupled at this same time as well. Redshift (z) is the increase of apparent wavelength of light coming toward an observer as the result of an object moving away from the observer where $1 + z = \frac{\lambda_{\rm obs}}{\lambda_{emit}}$. The radiation is a relic of the big-bang that is still observed today; it is called the Cosmic Microwave Background (CMB). The CMB is nearly isotropic blackbody radiation which expanded and cooled and fills the universe and is now at $T_{0}=2.725 \pm 0.002 K$. \citet{Burke_1997} Burke et al. (1997)  state that the isotropy of the CMB implies that sections of the Universe that were never in communication with one another have similar properties at the time of observation. 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}. \citet{Burke_1997} Burke (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} state that dark matter may be hot or cold - allowing for different levels of clustering in the Universe. The Hot Dark 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.