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arXiv · 1702.07710

Cosmological inviability of $f(R,T)$ gravity

Hermano Velten·Thiago R. P. Caramês
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Abstract

Among many alternative gravitational theories to General Relativity (GR), $f(R,T)$ gravity (where $R$ is the Ricci scalar and $T$ the trace of the energy-momentum tensor) has been widely studied recently. By adding a matter contribution to the gravitational Lagrangian, $f(R,T)$ theories have become an interesting extension to GR displaying a broad phenomenology in astrophysics and cosmology. In this paper, we discuss however the difficulties appearing in explaining a viable and realistic cosmology within the $f(R,T)$ class of theories. Our results challenge the viability of $f(R,T)$ as an alternative modification of gravity.

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Hermano Velten, Thiago R. P. Caramês. 2017-02-24. Cosmological inviability of $f(R,T)$ gravity. https://doi.org/10.1103/physrevd.95.123536

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