f(T,ℒm) Cosmology Embedded in a Viscous Barotropic Fluid
Abstract
We examine the cosmological dynamics of a viscous fluid within the framework of f(T,ℒm) gravity by using a barotropic equation of state for cosmic fluid. The modified Friedmann equations are used to construct an analytical Hubble model. Then H(z), Pantheon+SH0ES, DESI DR II BAO, and Cosmic Microwave Background datasets are used in a Bayesian Markov Chain Monte Carlo analysis to constrain its free parameters. Physically viable estimations of the Hubble constant and barotropic equation of state parameter are given by the obtained best-fit values. Based on the constrained parameters, we examine the redshift dependence of deceleration parameter, effective equation of state, dark energy equation of state, the effective pressure and viscous pressure quantities. While the deceleration parameter reveals how the universe evolved from an initially decelerating state to its present accelerating expansion, both equation of state parameters persist in the quintessence regime in the late epoch. Moreover, throughout the cosmic evolution, the viscous and effective pressures stay negative. The observational viability of the suggested viscous f(T,ℒm) cosmological model is supported by the estimated Hubble constant, whose values agree well with the results from independent cosmological observations.
Related
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- Cosmology with a Non-minimally Coupled Dark Matter Fluid II. Cosmological Perturbations
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BibTeX
@misc{behera2026ftℒm,
title = {{$f(T,\mathcalL_m)$ Cosmology Embedded in a Viscous Barotropic Fluid}},
author = {Suraj Kumar Behera and Raja Solanki and Pratik P. Ray},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.09169},
eprint = {2609.09169},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.09169},
}
RIS
TY - UNPB
TI - f(T,ℒ_m) Cosmology Embedded in a Viscous Barotropic Fluid
AU - Suraj Kumar Behera
AU - Raja Solanki
AU - Pratik P. Ray
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.09169
UR - https://arxiv.org/abs/2609.09169
AB - We examine the cosmological dynamics of a viscous fluid within the framework of f(T,ℒ_m) gravity by using a barotropic equation of state for cosmic fluid. The modified Friedmann equations are used to construct an analytical Hubble model. Then H(z), Pantheon+SH0ES, DESI DR II BAO, and Cosmic Microwave Background datasets are used in a Bayesian Markov Chain Monte Carlo analysis to constrain its free parameters. Physically viable estimations of the Hubble constant and barotropic equation of state parameter are given by the obtained best-fit values. Based on the constrained parameters, we examine the redshift dependence of deceleration parameter, effective equation of state, dark energy equation of state, the effective pressure and viscous pressure quantities. While the deceleration parameter reveals how the universe evolved from an initially decelerating state to its present accelerating expansion, both equation of state parameters persist in the quintessence regime in the late epoch. Moreover, throughout the cosmic evolution, the viscous and effective pressures stay negative. The observational viability of the suggested viscous f(T,ℒ_m) cosmological model is supported by the estimated Hubble constant, whose values agree well with the results from independent cosmological observations.
ER -