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arXiv · 1410.4190

Gravitational lensing in the strong field limit for Kar's metric

Carlos A. Benavides·Alejandro Cardenas-Avendano·Alexis Larranaga
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Abstract

In this paper we calculate the strong field limit deflection angle for a light ray passing near a scalar charged spherically symmetric object, described by a metric which comes from the low-energy limit of heterotic string theory. Then, we compare the expansion parameters of our results with those obtained in the Einstein's canonical frame, obtained by a conformal transformation, and we show that, at least at first order, the results do not agree.

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Carlos A. Benavides, Alejandro Cardenas-Avendano, Alexis Larranaga. 2014-10-15. Gravitational lensing in the strong field limit for Kar's metric. https://doi.org/10.1007/s10773-015-2861-2

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