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arXiv · 2305.06838

Gravitational signatures of a non--commutative stable black hole

N. Heidari·H. Hassanabadi·A. A. Araújo Filho·J. Kriz·S. Zare·P. J. Porfírio
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Abstract

This work investigates several key aspects of a non--commutative theory with mass deformation. We calculate thermodynamic properties of the system and compare our results with recent literature. We examine the \textit{quasinormal} modes of massless scalar perturbations using two approaches: the WKB approximation and the P\"oschl--Teller fitting method. Our results indicate that stronger non--commutative parameters lead to slower damping oscillations of gravitational waves and higher partial absorption cross sections. Furthermore, we study the geodesics of massless and massive particles, highlighting that the non--commutative parameter $\Theta$ significantly impacts the paths of light and event horizons. Also, we calculate the shadows, which show that larger values of $\Theta$ correspond to larger shadow radii, and provide some constraints on $\Theta$ applying the observation of Sgr $A^{*}$ from the Event Horizon Telescope. Finally, we explore the deflection angle in this context.

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N. Heidari, H. Hassanabadi, A. A. Araújo Filho, J. Kriz, S. Zare, P. J. Porfírio. 2023-05-11. Gravitational signatures of a non--commutative stable black hole. https://doi.org/10.1016/j.dark.2023.101382

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