Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology
Scientific paper
2010-11-18
Phys.Rev.D82:124047,2010
Astronomy and Astrophysics
Astrophysics
General Relativity and Quantum Cosmology
21 pages, 9 figures, accepted for publication in PRD
Scientific paper
10.1103/PhysRevD.82.124047
Naked singularities are hypothetical astrophysical objects, characterized by a gravitational singularity without an event horizon. Penrose has proposed a conjecture, according to which there exists a cosmic censor who forbids the occurrence of naked singularities. Distinguishing between astrophysical black holes and naked singularities is a major challenge for present day observational astronomy. A possibility of differentiating naked singularities from black holes is through the comparative study of thin accretion disks properties around rotating naked singularities and Kerr-type black holes, respectively. In the present paper, we consider accretion disks around rotating naked singularities, obtained as solutions of the field equations in the Einstein-massless scalar field theory. A first major difference between rotating naked singularities and Kerr black holes is in the frame dragging effect, the angular velocity of a rotating naked singularity being inversely proportional to its spin parameter. Due to the differences in the exterior geometry, the thermodynamic and electromagnetic properties of the disks are different for these two classes of compact objects, consequently giving clear observational signatures that could discriminate between black holes and naked singularities. For specific values of the spin parameter and of the scalar charge, the energy flux from the disk around a rotating naked singularity can exceed by several orders of magnitude the flux from the disk of a Kerr black hole. The conversion efficiency of the accreting mass into radiation by rotating naked singularities is always higher than the conversion efficiency for black holes. Thus, these observational signatures may provide the necessary tools from clearly distinguishing rotating naked singularities from Kerr-type black holes.
Harko Tiberiu
Kovács Zoltán
No associations
LandOfFree
Can accretion disk properties observationally distinguish black holes from naked singularities? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Can accretion disk properties observationally distinguish black holes from naked singularities?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Can accretion disk properties observationally distinguish black holes from naked singularities? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-536339