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arXiv · 2306.13218

A new $f(Q)$ cosmological model with $H(z)$ quadratic expansion

N. Myrzakulov·M. Koussour·Dhruba Jyoti Gogoi
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Abstract

We present a new $f(Q)$ cosmological model capable of reproducing late-time acceleration, i.e. $f\left( Q\right) = λ_{0}\left( λ+Q\right) ^{n}$ by supporting certain parametrization of the Hubble parameter. By using observational data from Hubble, Pantheon, and Baryonic Acoustic Oscillations (BAO) dataset, we investigate the constraints on the proposed quadratic Hubble parameter $H(z)$. This proposal caused the Universe to transition from its decelerated phase to its accelerated phase. Further, the current constrained value of the deceleration parameter from the combined Hubble+Pantheon+BAO dataset is $q_{0}=-0.285\pm 0.021$, which indicates that the Universe is accelerating. We also analyze the evolution of energy density, pressure, and EoS parameters to infer the Universe's accelerating behavior. Finally, we use a stability analysis with linear perturbations to assure the model's stability.

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N. Myrzakulov, M. Koussour, Dhruba Jyoti Gogoi. 2023-06-22. A new $f(Q)$ cosmological model with $H(z)$ quadratic expansion. https://doi.org/10.1016/j.dark.2023.101268

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