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arXiv · 2302.14104

Transit String Dark Energy Models in $f(Q)$ Gravity

Dinesh Chandra Maurya·Archana Dixit·Anirudh Pradhan
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Abstract

In this paper, we have investigated an anisotropic cosmological model in $f(Q)$ gravity with string fluid in LRS Bianchi type-I universe. We have considered the arbitrary function $f(Q)=Q+α\sqrt{~Q}+2Λ$ where $α$ is model free parameter and $Λ$ is the cosmological constant. We have established a relationship between matter energy density parameter $Ω_{m}$ and dark energy density parameter $Ω_Λ$ through Hubble function using using constant equation of state parameter $ω$. We have made observational constraint on the model using $χ^2$-test with observed Hubble datasets $H(z)$ and SNe Ia datasets, and obtained the best fit values of cosmological parameters. We have used these best fit values in the result and discussion. We have discussed our result with cosmographic coefficients and found a transit phase dark energy model. Also, we analyzed the Om diagnostic function for anisotropic universe and found that our model is quintessence dark energy model.

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Dinesh Chandra Maurya, Archana Dixit, Anirudh Pradhan. 2023-03-01. Transit String Dark Energy Models in $f(Q)$ Gravity. https://doi.org/10.1142/s0219887823501347

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