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Nariai metric is the first example of the singularity free model

Naresh Dadhich
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Abstract

This is just to point out that the Nariai metric is the first example of the singularity free expanding perfect fluid cosmological model satisfying the weak energy condition, $ρ>0, ρ+p=0$. It is a conformally non-flat Einstein space.

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Naresh Dadhich. 2001-06-07. Nariai metric is the first example of the singularity free model. https://arxiv.org/abs/gr-qc/0106023

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