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تسجيل مستخدم جديدOn The Temporal Evolution of Particle Production in $f(T)$ Gravity
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The thermodynamical study of the universe allow particle production in modified $f(T)$ ($T$ is the torsion scalar) theory of gravity within a flat FLRW framework for line element. The torsion scalar $T$ plays the same role as the Ricci scalar $R$ in the modified theories of gravity. We derived the $f(T)$ gravity models by taking $f(T)$ as the sum of $T$ and an arbitrary function of $T$ with three different arbitrary function. We observe that the particle production describes the accelerated expansion of the universe without a cosmological constant or any unknown quintessence component. Also, we discussed the supplementary pressure, particle number density and particle production rate for three cases.
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The recent article entitled Cosmological inviability of $f(R,T)$ gravity [Phys. Rev. D 95 (2017) 123536], by H. Velten and T.R.P. Caram^es, claims that the reference A transition from a decelerated to an accelerated phase of the universe expansion fr
om the simplest non-trivial polynomial function of T in the f(R,T) formalism by P.H.R.S. Moraes, G. Ribeiro and R.A.C. Correa [Astrophys. Space Sci. 361 (2016) 227] has problematic points concerning its mathematical approach and observable consequences. Velten and Caram^es argue that the equation of the scale factor evolution in time in the $f(R,T)=R+alpha T+beta T^{2}$ cosmology was erroneously calculated. One crucial consequence of the supposed corrected version of such an equation, presented by the authors in [Phys. Rev. D 95 (2017) 123536], would be the absence of the transition from a decelerated to an accelerated phase of the expansion of the universe, an outcome originally predicted by Moraes, Ribeiro and Correa. We show that the above claim is incorrect and that there are no inconsistencies with the results by Moraes, Ribeiro and Correa in the referred work. In particular, we show that Velten and Caram^es have incorrectly performed their calculations, invalidating all their mathematical and physical criticism regarding the article by Moraes, Ribeiro and Correa. In addition, we quote that the solutions obtained by Velten and Caram^es are unfeasible in view of their mathematical misunderstanding.
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