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arXiv · 2303.00665

A model-independent method with phantom divide line crossing in Weyl-type $f(Q,T)$ gravity

M. Koussour
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Abstract

We investigate the history of the cosmos using an extension of symmetric teleparallel gravity, namely Weyl-type $f(Q,T)$ gravity, where $Q$ represents the non-metricity scalar of space-time in the standard Weyl form, completely specified by the Weyl vector $w_{μ}$, and $T$ represents the trace of the matter energy-momentum tensor. We derive the Hubble parameter from the proposed form of the time-dependent deceleration parameter $q=A-% \frac{B}{H^{2}}$, where $A$ and $B$ are free constants and then use a model-independent method to apply it to the Friedmann equations of Weyl-type $f(Q,T)$ gravity. Further, we determine the best fit values of the model parameters using new Hubble sets of data of 31 points and Type Ia Supernovae (SNe Ia) sets of data of 1048 points. Finally, we examine the behavior of the effective equation of state~(EoS)~parameter and we observe that the best fit values of the model parameters supports a crossing of the phantom divide line i.e. $ω_{eff}=-1$ from $ω_{eff}>-1$ (quintessence phase) to $ω_{eff}<-1$ (phantom phase). According to the current study, Weyl-type $f(Q,T)$ gravity can give an alternative to dark energy (DE) in solving the existing cosmic acceleration.

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M. Koussour. 2023-03-01. A model-independent method with phantom divide line crossing in Weyl-type $f(Q,T)$ gravity. https://doi.org/10.1016/j.cjph.2023.04.003

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