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arXiv · 2407.12236

Cosmological constraints on dynamical dark energy model in $F(Q)$ gravity

Omar Enkhili·Safae Dahmani·Dalale Mhamdi·Taoufik Ouali·Ahmed Errahmani
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Abstract

Extended teleparallel gravity, characterized by $F(Q)$ function where $Q$ is the non-metricity scalar, is one of the most promising approaches to general relativity. In this paper, we reexamine a specific dynamical dark energy model, which is indistinguishable from the $\Lambda$CDM model at present time and exhibits a special event in the future, within $F(Q)$ gravity. To constrain the free parameters of the model, we perform a Markov Chain Monte Carlo (MCMC) analysis, using the last data from Pantheon$^{+}$ and the latest measurements of the H(z) parameter combined. On the basis of this analysis, we have find that our dynamical dark energy model, in the context of F(Q) gravity, lies in the quintessence regime rather than in the phantom regime as in the case of general relativity. Furthermore, this behaviour affects the future expansion of the Universe as it becomes decelerating at $1\sigma$ confidence level for $z<-0.5$ and showing a bounce at $z_{\text{B}}\approx -0.835$. Finally, we have support our conclusion with a cosmographic analysis.

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Omar Enkhili, Safae Dahmani, Dalale Mhamdi, Taoufik Ouali, Ahmed Errahmani. 2024-07-17. Cosmological constraints on dynamical dark energy model in $F(Q)$ gravity. https://doi.org/10.1140/epjc%2Fs10052-024-13143-4

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