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arXiv · 1712.08762

The Effects of Running Gravitational Coupling On Rotating Black Holes

Sumarna Haroon·Mubasher Jamil·Kai Lin·Petar Pavlovic·Marko Sossich·Anzhong Wang
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Abstract

In this work we investigate the consequences of running gravitational coupling on the properties of rotating black holes. Apart from the changes induced in the space-time structure of such black holes, we also study the implications to Penrose process and geodetic precession. We are motivated by the functional form of gravitational coupling previously investigated in the context of infra-red limit of asymptotic safe gravity theory. In this approach, the involvement of a new parameter $\tildeξ$ in this solution makes it different from Schwarzschild black hole. The Killing horizon, event horizon and singularity of the computed metric is then discussed. It is noticed that the ergosphere is increased as $\tildeξ$ increases. Considering the black hole solution in equatorial plane, the geodesics of particles, both null and time like cases, are explored. The effective potential is computed and graphically analyzed for different values of parameter $\tildeξ$. The energy extraction from black hole is investigated via Penrose process. For the same values of spin parameter, the numerical results suggest that the efficiency of Penrose process is greater in quantum corrected gravity than in Kerr Black Hole. At the end, a brief discussion on Lense-Thirring frequency is also done.

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Sumarna Haroon, Mubasher Jamil, Kai Lin, Petar Pavlovic, Marko Sossich, Anzhong Wang. 2018-06-14. The Effects of Running Gravitational Coupling On Rotating Black Holes. https://doi.org/10.1140/epjc%2Fs10052-018-5986-7

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