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arXiv · 1908.11712

The Lambert $W$ function: A newcomer in the Cosmology class?

Subhajit Saha·Kazuharu Bamba
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Abstract

We propose a novel equation of state (EoS) which explains the evolutionary history of a flat Friedmann-Lemaitre-Robertson-Walker (FLRW) Universe. The uniqueness of this EoS lies in the fact that it incorporates the Lambert $W$ function in a special fashion. It is explicitly demonstrated that with observationally relevant values of the unknown parameters $\vartheta_\mathrm{1}$ and $\vartheta_\mathrm{2}$, all the evolutionary phases of the Universe can be reproduced. Moreover, it also shows that the initial singularity is unavoidable and asserts that the late-time acceleration of the Universe would continue forever.

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Subhajit Saha, Kazuharu Bamba. 2019-08-29. The Lambert $W$ function: A newcomer in the Cosmology class?. https://doi.org/10.1515/zna-2019-0240

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