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arXiv · 1806.01966

Effects of modified gravity on the turnaround radius in cosmology

Shin'ichi Nojiri·Sergei D. Odintsov·Valerio Faraoni
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Abstract

We revisit the concept of turnaround radius in cosmology, in the context of modified gravity. While preliminary analyses were limited to scalar-tensor/$F(R)$ gravity, we extend the definition and the study of this quantity to a much broader class of theories including also quantum $R^2$ gravity. The turnaround radius is computed in terms of the parameters of the theory and it is shown that a deviation not larger than 10\% of this quantity from its value in Einstein's theory could constrain the model parameters and even rule out some current theories.

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Shin'ichi Nojiri, Sergei D. Odintsov, Valerio Faraoni. 2018-06-05. Effects of modified gravity on the turnaround radius in cosmology. https://doi.org/10.1103/physrevd.98.024005

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