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arXiv · 1909.06419

Null hypersurfaces in Kerr-(A)dS spacetimes

Abdulrahim Al Balushi·Robert B. Mann
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Abstract

For many purposes, a three-dimensional foliation of spacetime is more advantageous to understanding its light cone structure. We derive the equations describing such foliations for the Kerr geometry with non-zero cosmological constant, and show that they reduce to null hypersurfaces in vacuum (anti-)de Sitter spacetime in the limit of zero mass. Furthermore, we find that these null hypersurfaces are free of caustics everywhere for $r>0$. Our construction has applications in numerical studies of rotating black holes, and in defining Kruskal coordinates for rotating black holes with non-zero cosmological constant.

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Abdulrahim Al Balushi, Robert B. Mann. 2019-09-13. Null hypersurfaces in Kerr-(A)dS spacetimes. https://doi.org/10.1088/1361-6382%2Fab56ec

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