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arXiv · 2602.20563

Non-vacuum metrics for the Newman-Unti-Tamburino background: A coordinate-free approach to diverging and twisting solutions

Ayşe Hümeyra Bilge·Tolga Birkandan·Tekin Dereli·Gulay Karakaya
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Abstract

The geometry of the Newman-Unti-Tamburino (NUT) vacuum solution is characterized as the unique Petrov Type D vacuum metric such that the two double principal null directions form an integrable distribution. We study expanding and twisting non-vacuum Type D metrics in this geometry, with the additional assumption $\Phi_{01}=\Phi_{12}=0$. We prove that these conditions determine the solutions up to a freedom in $\Phi_{11}\pm 3\Lambda$.

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Ayşe Hümeyra Bilge, Tolga Birkandan, Tekin Dereli, Gulay Karakaya. 2026-02-24. Non-vacuum metrics for the Newman-Unti-Tamburino background: A coordinate-free approach to diverging and twisting solutions. https://doi.org/10.1007/s10773-026-06360-y

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