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arXiv · 2505.00208

Modified cosmology in $f(Q, L_m)$ gravity

Y. Myrzakulov·Alnadhief H. A. Alfedeel·M. Koussour·S. Muminov·E. I. Hassan·J. Rayimbaev
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Abstract

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann equations are derived for a matter-dominated universe, and an analytical solution is obtained. Using Hubble, Pantheon+, and joint datasets, we constrain the model parameters and examine their implications. The results indicate that the model accommodates varying $H_0$ values, contributing to the Hubble tension, while $n \neq 1$ suggests deviations from general relativity (GR). The deceleration parameter confirms a transition to acceleration at $z_t \approx 0.6 - 0.8$, with present values supporting cosmic acceleration. This model offers a viable alternative to GR-based cosmology.

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Y. Myrzakulov, Alnadhief H. A. Alfedeel, M. Koussour, S. Muminov, E. I. Hassan, J. Rayimbaev. 2025-04-30. Modified cosmology in $f(Q, L_m)$ gravity. https://doi.org/10.1016/j.physletb.2025.139506

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