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arXiv · 2507.10631

Large scale structure constraints and matter power spectrum in $f (Q,\mathcal{L}_{m})$ gravity

Praveen Kumar Dhankar·Albert Munyeshyaka·Saddam Hussain·Tom Mutabazi
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Abstract

In the present work, we take into account the dynamical system analysis to investigate the matter power spectrum within the framework of the $f(Q,\mathcal{L}_{m})$ gravitational theory. After obtaining autonomous dynamical system variables for two different particular pedagogical choices of $f(Q,\mathcal{L}_{m})$ models (A and B), we derive the full system of perturbation equations using the $1+3$ covariant formalism to study the matter fluctuations. We present and solve the energy density perturbation equations to obtain the energy density contrast, which decays with redshift for both models for a particular choice of model parameters. After obtaining the numerical results of the density contrast, we computed the matter spectra for each model and conducted a comparative analysis with the $\Lambda$CDM. Furthermore, by employing the Markov Chain Monte Carlo (MCMC) analysis,the model parameters were constrained using a combination of different observational data sets to improve the robustness and accuracy of the parameter estimation. Our results indicate that only model A can be compatible with the considered observational data sets.

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Praveen Kumar Dhankar, Albert Munyeshyaka, Saddam Hussain, Tom Mutabazi. 2025-07-14. Large scale structure constraints and matter power spectrum in $f (Q,\mathcal{L}_{m})$ gravity. https://arxiv.org/abs/2507.10631

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