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\section{Introduction}  \subsection{Big \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, but as the universe expanded and temperature decreased, at a redshift of z = 1000, matter and radiation became decoupled. As seen in figure 1, this occurred approximately 380 000 years after the Big Bang. Redshift 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 = λ_obsv/λ_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 T0=2 725 0 002 K. (B.F Burke and F Graham-Smith) states 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 observations .  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 in temperature and density in an isotropic homogeneous universe (Galaxy Formation and Evolution, Houjun Mo, Frank van den Bosch, Simon White). (B.F Burke and F Graham-Smith) further states that the same fluctuations/ irregularities would have been imprinted on the radiation that we now see as the CMB. The quantum fluctuations we regions whose density was slightly higher than the mean density of the universe. These regions of higher density attracted surrounding matter through gravity.