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arXiv · 2107.01455

Hawking-Ellis type of matter on Killing horizons in symmetric spacetimes

Hideki Maeda
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Abstract

Spherically, plane, or hyperbolically symmetric spacetimes with an additional hypersurface orthogonal Killing vector are often called ``static'' spacetimes even if they contain regions where the Killing vector is non-timelike. It seems to be widely believed that an energy-momentum tenor for a matter field compatible with these spacetimes in general relativity is of the Hawking-Ellis type I everywhere. We show in arbitrary $n(\ge 3)$ dimensions that, contrary to popular belief, a matter field on a Killing horizon is not necessarily of type I but can be of type II. Such a type-II matter field on a Killing horizon is realized in the Gibbons-Maeda-Garfinkle-Horowitz-Strominger black hole in the Einstein-Maxwell-dilaton system and may be interpreted as a mixture of a particular anisotropic fluid and a null dust fluid.

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Hideki Maeda. 2021-11-01. Hawking-Ellis type of matter on Killing horizons in symmetric spacetimes. https://doi.org/10.1103/physrevd.104.084088

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