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arXiv · 1908.11595

Thermodynamics and stability of $f(T,B)$ gravity with viscous fluid by observational constraints

A. Pourbagher·Alireza Amani
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Abstract

In this paper, we study the model of $f(T, B)$ gravity with viscous fluid in flat-FRW metric, in which $T$ and $B$ are torsion scalar and boundary term, respectively. We obtain the Friedmann equations in the framework of modified teleparallel gravity by tetrad components. We consider an interacting model between matter and dark energy so that universe dominates by viscous fluid. Then, we write the corresponding cosmological parameters in terms of the redshift parameter, and, we parameterize the Hubble parameter with experimental data. In what follows, we plot the corresponding cosmological parameters for dark energy components in terms of redshift, thereafter we investigate the accelerated expansion of the universe. Moreover, we discuss the stability of the model by using the sound speed parameter. Finally, we investigate the validity of the generalized second law of thermodynamics.

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A. Pourbagher, Alireza Amani. 2019-08-30. Thermodynamics and stability of $f(T,B)$ gravity with viscous fluid by observational constraints. https://doi.org/10.1007/s10509-019-3631-z

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