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arXiv · 2507.15754

Dynamical analysis of bulk viscous cosmological model in $F(T)$ gravity

Partha Sarathi Debnath·Chanchal Mondal·B. C. Paul
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Abstract

Bulk viscous cosmological models is presented in the teleparallel ($F(T)$, where $T$ denotes torsion) gravity. In the teleparallel gravity, the Lagrangian of the gravitational action contains a general function $F(T)= T+ f(T)=(1+ \gamma) T+\alpha (-T)^n$, where $\gamma$, $n$ and $\alpha$ are dimensional constants. Cosmological solutions in Eckart theory and Truncated Israel Stewart theory are talked about in $F(T)=(1+ \gamma) T+\alpha (-T)^n$ gravity form which is one of the most generalized gravity form in the torsional gravity. The substantial and geometrical prospective of the cosmological models in Eckart theory and Truncated Israel Stewart theory in $F(T)$ gravity are deliberated for flat Friedmann-Robertson-Walker space time. Dynamical analysis of the fixed points of exponential expansion in $F(T)$ with bulk viscous cosmological models are studied here. The characteristics of the various cosmological parameters such as bulk viscous pressure, energy density, scale factor, Hubble parameter and entropy evolution are studied in Power law and Exponential models. Stability analysis of the exponential models are also argued with cosmic growth in the relevant theories by using directional plots. The cosmological models are supported by observations results.

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Partha Sarathi Debnath, Chanchal Mondal, B. C. Paul. 2025-07-21. Dynamical analysis of bulk viscous cosmological model in $F(T)$ gravity. https://doi.org/10.1142/s0219887825501385

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