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arXiv · 1108.0191

Non-monotonic Keplerian velocity profiles around near-extreme braneworld Kerr black holes

Zdenek Stuchlik·Martin Blaschke·Petr Slany
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Abstract

We study the non-monotonic Keplerian velocity profiles related to locally non-rotating frames (LNRF) in the field of near-extreme braneworld Kerr black holes and naked singularities in which the non-local gravitational effects of the bulk are represented by a braneworld tidal charge $b$ and the 4D geometry of the spacetime structure is governed by the Kerr-Newman geometry. We show that positive tidal charge has a tendency to restrict the values of the black hole dimensionless spin $a$ admitting existence of the non-monotonic Keplerian LNRF-velocity profiles; the non-monotonic profiles exist in the black hole spacetimes with tidal charge smaller than $b=0.41005$ (and spin larger than $a=0.76808$). With decreasing value of the tidal charge (which need not be only positive), both the region of spin allowing the non-monotonicity in the LNRF-velocity profile around braneworld Kerr black hole and the velocity difference in the minimum-maximum parts of the velocity profile increase implying growing astrophysical relevance of this phenomenon.

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Zdenek Stuchlik, Martin Blaschke, Petr Slany. 2011-07-31. Non-monotonic Keplerian velocity profiles around near-extreme braneworld Kerr black holes. https://doi.org/10.1088/0264-9381%2F28%2F17%2F175002

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