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arXiv · 1601.07928

Viability of Arctan Model of f(R) Gravity for Late-time Cosmology

Koushik Dutta·Sukanta Panda·Avani Patel
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Abstract

$f(R)$ modifications of Einstein's gravity is an interesting possibility to explain the late time acceleration of the Universe. In this work we explore the cosmological viability of one such $f(R)$ modification proposed in (Kruglov:2013). We show that the model violates fifth-force constraints. The model is also plagued with the issue of curvature singularity in a spherically collapsing object, where the effective scalar field reaches to the point of diverging scalar curvature.

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Koushik Dutta, Sukanta Panda, Avani Patel. 2016-01-27. Viability of Arctan Model of f(R) Gravity for Late-time Cosmology. https://doi.org/10.1103/physrevd.94.024016

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