Eur. Phys. J. C (2018) 78: 405
https://doi.org/10.1140/epjc/s10052-018-5866-1

Regular Article - Theoretical Physics

Stephani cosmology: entropically viable but observationally challenged

¹ Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou, 225009, China
² School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
³ Department of Physics, Shahid Beheshti University, G.C., Evin, Tehran, 19839, Iran
⁴ Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai, 200240, China

^* e-mail: ycong@yzu.edu.cn

Received: 14 January 2018
Accepted: 3 May 2018
Published online: 23 May 2018

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-Da̧browski 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.