Quasinormal modes of nonlinearly charged black holes surrounded by a cloud of strings in Rastall gravity

In this paper, we obtain the black hole solution for the Ayon-Beato-Garcia (ABG)-type black hole surrounded by a cloud of strings in Rastall gravity and calculate the scalar quasinormal modes of it for a massless scalar field. To have a better visualization of the results, we also introduce a new nonlinear electrodynamic source and obtain a black hole solution surrounded by a cloud of strings in the Rastall gravity. We see that the quasinormal modes are affected by the type of nonlinear electrodynamic sources in case of higher magnitudes of charge q. With increase in the magnitude of charge q, gravitational waves decay rapidly for the new black hole solution, while for the ABG black hole, the decay rate increases initially and finally starts to decrease near to q = 1. We also study the impact of the cloud of strings and other model parameters, including the Rastall parameter on the quasinormal modes for both of the black holes. The gravitational waves decay slowly with increase in the cloud of strings parameter for both of the black holes. Dependency of quasinormal modes on the Rastall parameter is different from a surrounding dark energy field and the decay of gravitational waves may be slow or rapid depending on the value of this parameter.

Automated summary

In this paper, we study the black hole solution for the ABG-type black hole surrounded by a cloud of strings in Rastall gravity. We calculate the quasinormal modes and analyze the effects of nonlinear electrodynamic sources, the magnitude of charge, the cloud of strings parameter, and the Rastall parameter on these modes. The results show that the quasinormal modes are influenced by the type of nonlinear electrodynamic sources and the decay rate of gravitational waves depends on the magnitude of charge and the values of the model parameters.