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arXiv · 2606.23782

New Rotating Black Hole in Electromagnetic Fields: Cosmological Horizon without Cosmological Constant

Liang Ma·H. Lu
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Abstract

We obtain a new electrovacuum and related background spacetime that contains a cosmological horizon supported entirely by the electromagnetic field. The local solution belongs to the Kundt class of type D, but is globally distinct. We further construct an exact solution describing a Kerr black hole in this background. We study the global structure including horizons and singularities, and derive the first law of black hole thermodynamics. The emergence of a cosmological horizon in Einstein-Maxwell gravity without invoking a positive cosmological constant or dark energy is tantalizing, and may provide a new avenue for exploring cosmological and astrophysical phenomena related to black holes and the late-time cosmology.

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Liang Ma, H. Lu. 2026-06-22. New Rotating Black Hole in Electromagnetic Fields: Cosmological Horizon without Cosmological Constant. https://arxiv.org/abs/2606.23782

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