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arXiv · 2303.01541

Cosmology with viscous generalized Chaplygin gas in $f(Q)$ gravity

Gaurav N. Gadbail·Simran Arora·P. K. Sahoo
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Abstract

We use the hybrid model of bulk viscosity and generalized chaplygin gas (GCG), named the viscous generalized chaplygin gas (VGCG) model, which is thought to be an alternate dark fluid of the universe. We explore the dynamics of the VGCG model in the framework of the non-metricity $f(Q)$ gravity using the functional form $f(Q)=\beta Q^n$, where $\beta$ and $n$ are arbitrary constants. For the purpose of constraining model parameters, we use recent observational datasets such as Observational Hubble data, Baryon Acoustic Oscillations, and Type $Ia$ supernovae data. According to our study, the evolution of the deceleration parameter $q$ and the equation of state (EoS) parameter $w$ show a transition from deceleration to an acceleration phase and its deviation from the $\Lambda$CDM model.

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Gaurav N. Gadbail, Simran Arora, P. K. Sahoo. 2023-03-02. Cosmology with viscous generalized Chaplygin gas in $f(Q)$ gravity. https://doi.org/10.1016/j.aop.2023.169269

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