Exact formulas for spherical photon orbits around Kerr black holes

Date

2020-11-01

Author

Tavlayan, Aydın
Tekin, Bayram

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

223
views

0
downloads

Exact formulas relating the radii of the spherical photon orbits to the black hole's rotation parameter and the effective inclination angle of the orbit have been known only for equatorial and polar orbits up to now. Here we provide exact formulas for nonequatorial orbits that lie between these extreme limits. For a given rotation parameter of the black hole, there is a critical inclination angle below which there are four null photon orbits two of which are in the exterior region. At the critical angle, the radii of these orbits are explicitly found. We also provide approximate but very accurate formulas for any orbit. To arrive at these analytical solutions, we carefully study the sextic polynomial in the radius that arises for null spherical geodesics.

Subject Keywords

Physics and Astronomy (miscellaneous)

URI

https://hdl.handle.net/11511/69557

Journal

PHYSICAL REVIEW D

DOI

https://doi.org/10.1103/physrevd.102.104036

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Event horizon detecting invariants Tavlayan, Aydın; Tekin, Bayram (American Physical Society (APS), 2020-04-14) Some judiciously chosen local curvature scalars can be used to invariantly characterize event horizons of black holes inD > 3 dimensions, but they fail for the three dimensional Banados-Teitelboim-Zanelli (BTZ) black hole since all curvature invariants are constant. Here we provide an invariant characterization of the event horizon of the BTZ black hole using the curvature invariants of codimension one hypersurfaces instead of the full spacetime. Our method is also applicable to black holes in generic dimen...
Neutrino oscillations induced by spacetime torsion Adak, M; Dereli, T; Ryder, LH (IOP Publishing, 2001-04-21) The gravitational neutrino oscillation problem is studied by considering the Dirac Hamiltonian in a Riemann-Cartan spacetime and calculating the dynamical phase. Torsion contributions which depend on the spin direction of the mass eigenstates are found. These effects are of the order of Planck scales.
Symmetric Surface Momentum and Centripetal Force for a Particle on a Curved Surface Shikakhwa, M. S. (IOP Publishing, 2018-09-01) The Hermitian surface momentum operator for a particle confined to a 2D curved surface spanned by orthogonal coordinates and embedded in 3D space is expressed as a symmetric expression in derivatives with respect to the surface coordinates and so is manifestly along the surface. This is an alternative form to the one reported in the literature and usually named geometric momentum, which has a term proportional to the mean curvature along the direction normal to the surface, and so "apparently" not along the...
More on the classical double copy in three spacetime dimensions Gumus, Mehmet Kemal; Alkaç, Gökhan (American Physical Society (APS), 2020-07-01) It is well known that general relativity in three spacetime dimensions (3D) has no well-defined Newtonian limit. Recently, a static solution mimicking the behavior of the expected Newtonian potential has been found by studying the classical double copy of a point charge in gauge theory [M. Carrillo Gonzlez, B. Melcher, K. Ratliff, S. Watson, and C. D. White, J. High Energy Phys. 07 (2019) 167.]. This is the first example where the vacuum solution in the gauge theory leads to a nonvacuum solution on the grav...
COLLIDING ABELIAN GAUGE PLANE-WAVES GURSES, M; Karasu, Emine Ayşe (IOP Publishing, 1989-04-01) The characteristic initial-value problem of the gravitational and N-Maxwell plane wave collision is solved exactly.

Citation Formats

A. Tavlayan and B. Tekin, “Exact formulas for spherical photon orbits around Kerr black holes,” PHYSICAL REVIEW D, pp. 0–0, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/69557.