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Galaxies 2018, 6(4), 107;

Testing the Anomalous Growth of the Black Hole Radius from AGN

Center for Field Theory and Particle Physics, Department of Physics, Fudan University, Shanghai 200433, China
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Received: 18 July 2018 / Revised: 17 September 2018 / Accepted: 20 September 2018 / Published: 3 October 2018
PDF [393 KB, uploaded 19 October 2018]


We analyze constraints on the anomalous growth of the black hole radius or the black hole spin from the X-rays spectrum data of Active Galactic Nuclei (AGN) in NGC 5506. The anomalous growth of the mass or of the spin of a black hole may be unveiled within the framework of models of alternative gravity, including f ( R ) -gravity. Our phenomenological analysis is based on an effective parametrization for the black hole Kerr metric, which is inspired by the antievaporating solutions discovered by Nojiri and Odintsov. We find tight constraints on the parameter space of anomalous metrics. Intriguingly, we find that a more than secularly growing solution can better fit current data. Our result opens a pathway towards a new phenomenological approach for testing predictions of general relativity and alternative theories of gravity. View Full-Text
Keywords: alternative gravity; black holes; gravitational instabilities; AGN physics alternative gravity; black holes; gravitational instabilities; AGN physics

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Addazi, A.; Marciano, A.; Qian, C. Testing the Anomalous Growth of the Black Hole Radius from AGN. Galaxies 2018, 6, 107.

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