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arXiv · 1712.02297

Stephani Cosmology: Entropically Viable But Observationally Challenged

Yen Chin Ong·S. Sedigheh Hashemi·Rui An·Bin Wang
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Abstract

Inhomogeneous cosmological models such as the Stephani universes could, in principle, provide an explanation for the observed accelerated expansion of the Universe. Working with a concrete, popular model of the Stephani cosmology -- the Stephani-Dabrowski model, we found that it is entropically viable. We also comment on the energy conditions and the two-sheeted geometry of the spacetime. However, similar to the LTB models, despite satisfying the holographic principle, Stephani cosmology has difficulty satisfying all the constraints from observations.

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Yen Chin Ong, S. Sedigheh Hashemi, Rui An, Bin Wang. 2018-05-31. Stephani Cosmology: Entropically Viable But Observationally Challenged. https://doi.org/10.1140/epjc%2Fs10052-018-5866-1

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