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Dynamical Constraints on the Cosmological Parameters

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 نشر من قبل Ying-Qiu Gu
 تاريخ النشر 2017
  مجال البحث فيزياء
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 تأليف Ying-Qiu Gu




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In cosmology, the cosmic curvature $K$ and the cosmological constant $Lambda$ are two important parameters, and the values have strong influence on the behavior of the universe. In the context of normal cosmology, under the ordinary assumptions of positive mass-energy and initial negative pressure, we find the initial singularity of the universe is certainly absent and we have $K=1$. This means total spatial structure of the universe should be a 3-dimensional sphere $S^3$. For the cyclic cosmological model, we have $Lambdalesssim 10^{-24} {rm ly}^{-2}$. Obviously, such constraints would be helpful for the researches on the properties of dark matter and dark energy in cosmology.



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