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Kretschmann Scalar for a Kerr-Newman Black Hole

Richard C. Henry
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Abstract

I have derived the Kretschmann scalar for a general black hole of mass m, angular momentum per unit mass a, and electric charge Q. The Kretschmann scalar gives the amount of curvature of spacetime, as a function of position near (and within) a black hole. This allows one to display the "appearance" of the black hole itself, whether the black hole is merely of stellar mass, or is a supermassive black hole at the center of an active galaxy. Schwarzschild black holes, rotating black holes, electrically charged black holes, and rotating electrically-charged black holes, are all illustrated. Rotating black holes are discovered to possess a negative curvature that is not analagous to that of a saddle.

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BibTeXRIS

Richard C. Henry. 1999-12-15. Kretschmann Scalar for a Kerr-Newman Black Hole. https://doi.org/10.1086/308819

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