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arXiv · 2109.04229

Regularized big bang singularity: Geodesic congruences

Z. L. Wang
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Abstract

We investigate a particular regularization of big bang singularity, which remains within the domain of 4-dimensional general relativity but allowing for degenerate metrics. We study the geodesics and geodesic congruences in the modified Friedmann-Lema\^itre-Robertson-Walker universe. In particular, we calculate the expansion of timelike and null geodesic congruences. Based on these results, we also briefly discuss the cosmological singularity theorems.

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Z. L. Wang. 2021-09-09. Regularized big bang singularity: Geodesic congruences. https://doi.org/10.1103/physrevd.104.084093

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