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arXiv · 2412.08844

Zero Mass limit of Kerr-MOG Black Hole Equals Wormhole

Parthapratim Pradhan·John W. Moffat
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Abstract

It has been argued in existing literature that the zero mass limit of Kerr spacetime corresponds to either flat Minkowski spacetime or a wormhole exhibiting a locally flat geometry. In this study, we examine that the zero mass limit of the Kerr-MOG black hole is equivalent to a wormhole. Moreover, we derive the Kerr-Schild form of the Kerr-MOG black hole through specific coordinate transformations. We further investigate the physical and topological characteristics of the Kerr-MOG black hole within the framework of modified gravity. Our analysis also includes a discussion of the wormhole using cylindrical coordinates, which comprises two distinct coordinate patches. Furthermore, we extend our analysis to the Kerr-Newman black hole and show that the \emph{zero mass limit of the Kerr-Newman black hole does not yield a wormhole}. However, if we impose an additional criterion such that \emph{both the mass parameter and the charge parameters are equal to zero}, then the Kerr-Newman black hole will be a wormhole.

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Parthapratim Pradhan, John W. Moffat. 2024-12-12. Zero Mass limit of Kerr-MOG Black Hole Equals Wormhole. https://doi.org/10.1103/physrevd.111.064013

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