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arXiv · 0902.3107

Barotropic index w-singularities in cosmology

Mariusz P. Dabrowski·Tomasz Denkiewicz
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Abstract

We find an explicit cosmological model which allows a special type of cosmological singularity which we call a $w$-singularity. This singularity has the scale factor finite, the energy density and pressure vanishing, and the only singular behaviour appears in a time-dependent barotropic index $w(t)$. It is different from the type IV cosmological singularity in that it does not exhibit the divergence of the higher derivatives of the Hubble parameter and from the big-brake since it does not fulfill the anti-Chaplygin gas equation of state. We also find an interesting duality between the $w$-singularities and the big-bang singularities. Physical examples of $w$-singularities appear in $f(R)$, scalar field and brane cosmologies.

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Mariusz P. Dabrowski, Tomasz Denkiewicz. 2009-04-17. Barotropic index w-singularities in cosmology. https://doi.org/10.1103/physrevd.79.063521

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