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arXiv · 2405.15883

The estimation of parameters of generalized cosmic Chaplygin gas and viscous modified Chaplygin gas and Accretions around Black Hole in the background of Einstein-Aether gravity

Puja Mukherjee·Ujjal Debnath·Himanshu Chaudhary·G. Mustafa
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Abstract

In this paper, we have investigated the phenomenon of accelerated cosmic expansion in the late universe and the mass accretion process of a 4-dimensional Einstein-Aether black hole. Starting with the basics of Einstein-Aether gravity theory, we have first considered the field equations and two eminent models of Chaplygin gas, viz. generalized cosmic Chaplygin gas model and viscous modified Chaplygin gas model. Then, we obtained the energy density and Hubble parameters equations for these models in terms of some dimensionless density parameters and some unknown parameters. After finding the required parameters, we proceeded with the mass accretion process. For both models, we obtained the equation of mass in terms of the redshift function and represented the change of mass of the black hole graphically with redshift. At the same time, we have made a graphical comparison between the above-mentioned models and the $\Lambda$CDM model of the universe. Eventually, we have concluded that the mass of a 4-dimensional black hole will increase along the universe's evolution in the backdrop of Einstein-Aether gravity.

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Puja Mukherjee, Ujjal Debnath, Himanshu Chaudhary, G. Mustafa. 2024-05-24. The estimation of parameters of generalized cosmic Chaplygin gas and viscous modified Chaplygin gas and Accretions around Black Hole in the background of Einstein-Aether gravity. https://arxiv.org/abs/2405.15883

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