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arXiv · 2008.09908

Black Hole Shadows in M-theory Scenarios

A. Belhaj·M. Benali·A. El Balali·W. El Hadri·H. El Moumni·E. Torrente-Lujan
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Abstract

We study the shadows of four dimensional black holes in M-theory inspired models. We first inspect the influence of M2-branes on such optical aspects for non-rotating solutions. In particular, we show that the M2-brane number can control the circular shadow size. This geometrical behavior is distorted for rotating solutions exhibiting cardioid shapes in certain moduli space regions. Implementing a rotation parameter, we analyze the geometrical shadow deformations. Among others, we recover the circular behaviors for a large M2-brane number. Investigating the energy emission rate at high energies, we find, in a well-defined approximation, that the associated peak decreases with the M2-brane number. Moreover, we investigate a possible connection with observations (from Event Horizon Telescope or future devices) from a particular M-theory compactification by deriving certain constraints on the M2-brane number in the light of the $M87^\star$ observational parameters.

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A. Belhaj, M. Benali, A. El Balali, W. El Hadri, H. El Moumni, E. Torrente-Lujan. 2020-08-22. Black Hole Shadows in M-theory Scenarios. https://doi.org/10.1142/s0218271821500267

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