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arXiv · 1603.02851

On stability of the Kasner solution in quadratic gravity

A. Toporensky·D. Müller
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Abstract

We consider dynamics of a flat anisotropic Universe filled by a perfect fluid near a cosmological singularity in quadratic gravity. Two possible regimes are described -- the Kasner anisotropic solution and an isotropic "vacuum radiation" solution which has three sub cases depending on whether the equation of state parameter $w$ is bigger, smaller or equals to $1/3$. Initial conditions for numerical integrations have been chosen near General Relativity anisotropic solution with matter (Jacobs solution). We have found that for such initial conditions there is a range of values of coupling constants so that the resulting cosmological singularity is isotropic.

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A. Toporensky, D. Müller. 2016-03-09. On stability of the Kasner solution in quadratic gravity. https://doi.org/10.1007/s10714-016-2172-9

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