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arXiv · 2007.11350

Reversing the Null Limit of the Szekeres Metric

Charles Hellaby·Otakar Svítek
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Abstract

The null limits of the Lemaitre-Tolman and Szekeres spacetimes are known to be the Vaidya and news-free Robinson-Trautman metrics. We generalise this result to the case of non-zero $Λ$, and then ask whether the reverse process is possible -- is there a systematic procedure to retrieve the timelike-dust metric from the null-dust case? We present such an algorithm for re-constructing both the metric and matter tensor components of the timelike-dust manifold. This undertaking has elucidated the null limit process, highlighted which quantities approach unity or zero, and necessitated a careful discussion of how the functional dependencies are managed by the transformations and substitutions used.

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Charles Hellaby, Otakar Svítek. 2020-11-28. Reversing the Null Limit of the Szekeres Metric. https://doi.org/10.1088/1361-6382%2Fabcc0c

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