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arXiv · 2303.16924

Regular Black Holes and Stars from Analytic $f(F^2)$

Zhi-Chao Li·H. Lu
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Abstract

We construct regular black holes and stars that are geodesically complete and satisfy the dominant energy condition from Einstein-$f(F^2)$ gravities with several classes of analytic $f(F^2)$ functions that can be viewed as perturbations to Maxwell's theory in weak field limit. We establish that regular black holes with special static metric ($g_{tt} g_{rr}=-1$) violate the strong energy condition and such a regular black hole with Minkowski core violates the null energy condition. We develop a formalism to perform electromagnetic duality transformations in $f(F^2)$. We obtain two new explicit examples where the duality is a symmetry. We study the properties of the corresponding dyonic black holes. We study the geodesic motions of a particular class of solutions that we call repulson stars or black holes.

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Zhi-Chao Li, H. Lu. 2023-03-29. Regular Black Holes and Stars from Analytic $f(F^2)$. https://arxiv.org/abs/2303.16924

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