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arXiv · 1910.11066

Super-horizon effects on the gauge invariant effective energy density in f(R) gravity

S. Cheraghchi·F. Shojai
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Abstract

In this article we study the gauge invariant effective energy momentum tensor for cosmological perturbations in f(R) gravity during the inflationary epoch. Considering the super-horizon regime, we derive the effective energy density up to the one-loop corrections. It describes the back-reaction effect of the fluctuations on the background space-time.

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S. Cheraghchi, F. Shojai. 2019-10-24. Super-horizon effects on the gauge invariant effective energy density in f(R) gravity. https://doi.org/10.1103/physrevd.100.103509

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