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Title: Gravitational lensing by rotating naked singularities

Abstract

We model massive compact objects in galactic nuclei as stationary, axially symmetric naked singularities in the Einstein-massless scalar field theory and study the resulting gravitational lensing. In the weak deflection limit we study analytically the position of the two weak field images, the corresponding signed and absolute magnifications as well as the centroid up to post-Newtonian order. We show that there are static post-Newtonian corrections to the signed magnification and their sum as well as to the critical curves, which are functions of the scalar charge. The shift of the critical curves as a function of the lens angular momentum is found, and it is shown that they decrease slightly for the weakly naked and vastly for the strongly naked singularities with the increase of the scalar charge. The pointlike caustics drift away from the optical axis and do not depend on the scalar charge. In the strong deflection limit approximation, we compute numerically the position of the relativistic images and their separability for weakly naked singularities. All of the lensing quantities are compared to particular cases as Schwarzschild and Kerr black holes as well as Janis-Newman-Winicour naked singularities.

Authors:
 [1];  [1];  [2]
  1. Department of Theoretical Physics, Faculty of Physics, Sofia University, 5 James Bourchier Boulevard, 1164 Sofia (Bulgaria)
  2. (Germany)
Publication Date:
OSTI Identifier:
21254374
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 78; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.78.083004; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ANGULAR MOMENTUM; APPROXIMATIONS; AXIAL SYMMETRY; BLACK HOLES; CORRECTIONS; DIAGRAMS; FIELD THEORIES; GALAXY NUCLEI; GRAVITATIONAL LENSES; KERR FIELD; NUCLEI; RELATIVISTIC RANGE; SCALAR FIELDS; SIMULATION; SINGULARITY

Citation Formats

Gyulchev, Galin N., Yazadjiev, Stoytcho S., and Institut fuer Theoretische Physik, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen. Gravitational lensing by rotating naked singularities. United States: N. p., 2008. Web. doi:10.1103/PHYSREVD.78.083004.
Gyulchev, Galin N., Yazadjiev, Stoytcho S., & Institut fuer Theoretische Physik, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen. Gravitational lensing by rotating naked singularities. United States. doi:10.1103/PHYSREVD.78.083004.
Gyulchev, Galin N., Yazadjiev, Stoytcho S., and Institut fuer Theoretische Physik, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen. 2008. "Gravitational lensing by rotating naked singularities". United States. doi:10.1103/PHYSREVD.78.083004.
@article{osti_21254374,
title = {Gravitational lensing by rotating naked singularities},
author = {Gyulchev, Galin N. and Yazadjiev, Stoytcho S. and Institut fuer Theoretische Physik, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen},
abstractNote = {We model massive compact objects in galactic nuclei as stationary, axially symmetric naked singularities in the Einstein-massless scalar field theory and study the resulting gravitational lensing. In the weak deflection limit we study analytically the position of the two weak field images, the corresponding signed and absolute magnifications as well as the centroid up to post-Newtonian order. We show that there are static post-Newtonian corrections to the signed magnification and their sum as well as to the critical curves, which are functions of the scalar charge. The shift of the critical curves as a function of the lens angular momentum is found, and it is shown that they decrease slightly for the weakly naked and vastly for the strongly naked singularities with the increase of the scalar charge. The pointlike caustics drift away from the optical axis and do not depend on the scalar charge. In the strong deflection limit approximation, we compute numerically the position of the relativistic images and their separability for weakly naked singularities. All of the lensing quantities are compared to particular cases as Schwarzschild and Kerr black holes as well as Janis-Newman-Winicour naked singularities.},
doi = {10.1103/PHYSREVD.78.083004},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 78,
place = {United States},
year = 2008,
month =
}
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