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arXiv · 1905.12421

Hunting for extra dimensions in the shadow of M87*

Sunny Vagnozzi·Luca Visinelli
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Abstract

The Event Horizon Telescope has recently provided the first image of the dark shadow around the supermassive black hole M87*. The observation of a highly circular shadow provides strong limits on deviations of M87*'s quadrupole moment from the Kerr value. We show that the absence of such a deviation can be used to constrain the physics of extra dimensions of spacetime. Focusing on the Randall-Sundrum AdS$_5$ brane-world scenario, we show that the observation of M87*'s dark shadow sets the limit $\ell \lesssim 170\,{\rm AU}$, where $\ell$ is the AdS$_5$ curvature radius. This limit is among the first quantitative constraints on exotic physics obtained from the extraordinary first ever image of the dark shadow of a black hole.

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Sunny Vagnozzi, Luca Visinelli. 2019-07-12. Hunting for extra dimensions in the shadow of M87*. https://doi.org/10.1103/physrevd.100.024020

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