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arXiv · 2604.11821

Polytropic $f(Q)$ cosmology and its implications for the $H_0$ tension

Raja Solanki
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Abstract

Understanding the late-time cosmic phenomenon of the universe commonly referred to as the dark energy problem, which is one of the prominent tension in the field of theoretical as well as observational cosmology. In this work, we attempt to analyze the nature of the missing fluid of the universe. In order to do so, we employ a poly tropic equation of state consisting of free parameters rather assuming directly a particular form of the fluid. In addition, for the background geometry we consider a $f(Q)$ cosmology exhibiting power-law assumption, which is recently proposed and found to be attractive in the study of late-time cosmology. We find exact cosmological solution along with a rigorous data analysis, utilizing the Bayesian statistics approach and the emcee ensemble sampler, to find the parameter constraints and then we interpret the parameters of physical interests such as deceleration and statefinder parameter. Also, we present status of the $H_0$ tension predicted by our polytropic $f(Q)$ cosmological model.

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Raja Solanki. 2026-04-11. Polytropic $f(Q)$ cosmology and its implications for the $H_0$ tension. https://doi.org/10.1016/j.physletb.2026.140413

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