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arXiv · 2305.09706

Is it possible to distinguish between different black hole solutions using the Shapiro time delay?

Ednaldo L. B. Junior·Manuel E. Rodrigues·Henrique A. Vieira
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Abstract

In this paper we propose to use Shapiro time delay as a tool to distinguish between different black hole solutions. We calculate the analytic Shapiro time, using first-order expansions, for four solutions. They are Schwarzschild, Reissner-Nordstr\"o{}m, Bardeen, and Ay\'on-Beato and Garc\'ia. We created a numerical experiment, based on measurements made in the solar system, consisting of the round trip path of light passing through a black hole at the center. We obtained different delay times varying between the order of $10^{-4}$s and $10^{-6}$s, for a stellar black hole; and variations of the order of hours, for a supermassive one. Considering that the accuracy currently achieved in measurements made in the solar system are on the order of $10^{-12}$s, we believe that this mechanism could be used in black hole model determination in the near future.

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Ednaldo L. B. Junior, Manuel E. Rodrigues, Henrique A. Vieira. 2023-05-16. Is it possible to distinguish between different black hole solutions using the Shapiro time delay?. https://doi.org/10.1140/epjc/s10052-023-11520-z

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