Kantowski-Sachs universe cannot be closed

Abstract

In this paper, by analyzing the instability against spatially homogeneous and anisotropic perturbations of the Kantowski-Sachs-type during different cosmological epoch, we show that it is a theoretical consequence of the general relativity that the KS universe must be open or flat if it underwent the matter dominated and/or radiation dominated era in its past evolution, which theoretically confirms the flatness of our observable universe.

8 pages, to be published in Phys. Rev. D

References in corpus (4)

• Precision Cosmology? Not Just Yet
• On the Stability of the Einstein Static Universe
• Bianchi IX Brane-world Cosmologies
• Multidimensional Cosmology: Spatially Homogeneous models of dimension 4+1

Cited by in corpus (8)

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• Dynamics of the anisotropic Kantowsky-Sachs geometries in $R^n$ gravity
• Qualitative analysis of Kantowski-Sachs metric in a generic class of $f(R)$ models
• New mechanism to cross the phantom divide
• A nonsingular, anisotropic universe in a black hole with torsion and particle production
• An anisotropic Kantowski-Sachs universe with radiation, dust and a phantom fluid
• Anisotropic higher derivative gravity and inflationary universe
• Thermodynamic Interpretation of the Kompanneets-Chernov-Kantowski-Sachs Solutions