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\subsection{Galaxy Evolution: from the Big Bang to present day}  The Big Bang was 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 $1 + z = \lambda_{\rm obs}/ \lambda_{emit}$. \farc{\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 $T_{0}=2.725 \pm 0.002 K$. \cite{Burke_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}. \cite{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.