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Regularized big bang singularity: Geodesic congruences

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 نشر من قبل Zi-Liang Wang
 تاريخ النشر 2021
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Z.L. Wang




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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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