Series Vol. 5 , 25 May 2023
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As a drawback to the widely accepted standard Big Bang model, the Flatness problem has been highly controversial. Due to the presence of dark matter and difficulty in measuring distances between galaxies, the universe's density in the present day has high uncertainty. There are three models consistent with the cosmological principle. The Flatness problem originated from the uncertainty of the density parameter and the puzzling fine-tuning of omega and the point of the Big Bang; its potential to identify a shortcoming in the standard cosmological model has drawn considerable attention from the scientific community. Different approaches were taken as attempts to resolve this problem. However, arguments against the Flatness problem have also been proposed, disproving the existence of the Flatness problem from the perspective of classical cosmology. This paper examines the Flatness problem by quantitatively describing the flatness problem, presenting the historical development of the Flatness problem, analyzing past approaches to the Flatness problem, and considering arguments against the problem from the perspective of classical cosmology.
Flatness problem, Big Bang model, cosmology theory.
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The datasets used and/or analyzed during the current study will be available from the authors upon reasonable request.