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arXiv · 1701.01027

The Starobinsky model within the $f(R,T)$ formalism as a cosmological model

P. H. R. S. Moraes·R. A. C. Correa·G. Ribeiro
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Abstract

In this paper we derive a cosmological model from the $f(R,T)$ theory of gravity, for which $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. We consider $f(R,T)=f(R)+f(T)$, with $f(R)$ being the Starobinksy model $R+\alpha R^{2}$ and $f(T)=\gamma T$, with $\alpha$ and $\gamma$ constants. We find that from such a functional form, it is possible to describe the cosmological scenario of a radiation-dominated universe, which has shown to be a non-trivial feature within the $f(R,T)$ formalism.

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P. H. R. S. Moraes, R. A. C. Correa, G. Ribeiro. 2016-12-26. The Starobinsky model within the $f(R,T)$ formalism as a cosmological model. https://arxiv.org/abs/1701.01027

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