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arXiv · 0712.0272

Instability of scalar perturbation in a phantomic cosmological scenario

J. C. Fabris·D. F. Jardim·S. V. B. Goncalves
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Abstract

Scalar perturbations can grow during a phantomic cosmological phase as the big rip is approached, in spite of the high accelerated expansion regime, if the equation of state is such that $\frac{p}ρ = α< - {5/3}$. It is shown that such result is independent of the spatial curvature. The perturbed equations are exactly solved for any value of the curvature parameter $k$ and of the equation of state parameter $α$. Growing modes are found asymptotically under the condition $α< - {5/3}$. Since the Hubble radius decreases in a phantom universe, such result indicates that a phantom scenario may not survive longtime due to gravitational instability.

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J. C. Fabris, D. F. Jardim, S. V. B. Goncalves. 2007-12-03. Instability of scalar perturbation in a phantomic cosmological scenario. https://doi.org/10.1209/0295-5075%2F82%2F69001

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