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arXiv · 2006.09172

Thermodynamics of the viscous $f(T, B)$ gravity in the new agegraphic dark energy model

A. Pourbagher·Alireza Amani
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Abstract

In this paper, we first obtain the energy density by the approach of the new agegraphic dark energy model, and then the $f(T,B)$ gravity model is studied as an alternative to the dark energy in a viscous fluid by flat-FRW background, in which $T$ and $B$ are torsion scalar and boundary term. The Friedmann equations will obtain in the framework of modified teleparallel gravity by tetrad components. We consider that the universe dominates with components such as matter and dark energy by an interacting model. The Hubble parameter is parameterized by the power-law for the scale factor, and then we fit the corresponding Hubble parameter with observational data constraints. The variation of the equation of state (EoS) for dark energy is plotted as a function of the redshift parameter, and the accelerated expansion of the universe is explored. In what follows, the stability of the model is also studied on the base of the sound speed parameter. Finally, the generalized second law of thermodynamics is investigated by entropies of inside and on the boundary of the apparent horizon in thermodynamics equilibrium.

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A. Pourbagher, Alireza Amani. 2020-06-13. Thermodynamics of the viscous $f(T, B)$ gravity in the new agegraphic dark energy model. https://doi.org/10.1142/s0217732320501667

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