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arXiv · 1610.07300

Horndeski/Galileon black hole shadows

D. A. Tretyakova·T. M. Adyev
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Abstract

We examine observational signatures of the asymptotically de Sitter branch of static spherically symmetric Horndeski/Galileon solutions. Our analysis reveales that possible deviations of the photon sphere size from those of the GR Schwarzshild solution are vanishing compared to the resolution of modern radio-interferometric observations. These deviations are heavily suppressed by the bounds coming from the weak-field observation. We conclude that shadow size would not be a useful characteristic to distinguish the Horndeski/Galileon static spherically symmetric spacetimes in the foreseeable future.

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D. A. Tretyakova, T. M. Adyev. 2016-10-24. Horndeski/Galileon black hole shadows. https://arxiv.org/abs/1610.07300

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