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arXiv · 2411.04757

Quintessence phase of the late-time Universe in $f(Q,T)$ gravity

Shambel Sahlu·Bhupendra Kumar Shukla·Rishi Kumar Tiwari·Değer Sofuoğlu·Alnadhief H. A. Alfedeel
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Abstract

In this paper, we have studied the late-time accelerating expansion of the Universe using the matter-geometry coupled $ f(Q, T) $ gravity model, where $ Q $ is the non-metricity scalar and $ T $ represents the trace of the energy-momentum tensor. We constrain the best-fit values of cosmological parameters $\Omega_{m0}, H_0, \alpha_0~\mbox{and}~ \beta_0$ through the Monte Carlo Markov Chain (MCMC) simulation {using 31 Hubble parameter data points from cosmic chronometers (CC) and 26 data points from baryon acoustic oscillations (BAO), making a total of 57 datasets (labeled \texttt{CC+BAO}), as well as SNIa distance moduli measurements from the Pantheon+ sample, which consists of 1701 light curves of 1550 distinct supernovae (labeled \texttt{Pantheon +SHOES}), and their combination (labeled \texttt{CC+BAO+Pantheon +SHOES)}}. {We compare our constrained Hubble constant $H_0$ value with different late-time and early-time cosmological measurements.} Deceleration {parameter} \(q(z)\), effective equation of state parameters \(w_{eff}(z)\), Hubble parameter $H(z)$, and distance modulus \(\mu(z)\) are numerical results of dynamical quantities that show that the $f(Q, T)$ gravity model is compatible with a transition towards a quintessence-like phase in the late-time. In conformity with \(\Lambda\)CDM, we moreover take into account the geometrical interpretations by considering the state-finder parameters \(r-s\) and \(r-q\), which are crucial parameters for additional analysis. Additionally, the statistical analysis has been carried out for further investigation.

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Shambel Sahlu, Bhupendra Kumar Shukla, Rishi Kumar Tiwari, Değer Sofuoğlu, Alnadhief H. A. Alfedeel. 2024-11-07. Quintessence phase of the late-time Universe in $f(Q,T)$ gravity. https://arxiv.org/abs/2411.04757

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