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arXiv · 0709.2414

Dynamical Constraints on the Cosmological Parameters

Ying-Qiu Gu
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Abstract

In cosmology, the cosmic curvature $K$ and the cosmological constant $Λ$ 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 $Λ\lesssim 10^{-24} {\rm ly}^{-2}$. Obviously, such constraints would be helpful for the researches on the properties of dark matter and dark energy in cosmology.

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Ying-Qiu Gu. 2017-08-10. Dynamical Constraints on the Cosmological Parameters. https://arxiv.org/abs/0709.2414

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