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Gravitational lensing by a charged black hole of string theory

A. Bhadra
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Abstract

We study gravitational lensing by the Gibbons-Maeda-Garfinkle-Horowitz-Strominger (GMGHS) charged black hole of heterotic string theory and obtain the angular position and magnification of the relativistic images. Modeling the supermassive central object of the galaxy as a GMGHS black hole, we estimate the numerical values of different strong-lensing parameters. We find that there is no significant string effect present in the lensing observables in the strong-gravity scenario.

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BibTeXRIS

A. Bhadra. 2003-06-04. Gravitational lensing by a charged black hole of string theory. https://doi.org/10.1103/physrevd.67.103009

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