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arXiv · 1712.09522

Cosmological Inflation in a Generalized Unimodular Gravity

K. Nozari·S. Shafizadeh
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Abstract

We study some aspects of cosmological inflation in the framework of unimodular $f(R)$ gravity. To be more clarified, we consider a generic $f(R)$ of the type $f(R)=R+αR^{n}$. By considering Einstein frame counterpart of the unimodular $f(R)$ gravity, we set the scalaron to be responsible for cosmological inflation in this setup. We confront our model parameters space with observational data and impose some constraints on the value of $n$ in this manner. We show that for the number of e-folds $N=60$, the model is consistent with observation if $1.89<n<1.918$.

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K. Nozari, S. Shafizadeh. 2017-12-27. Cosmological Inflation in a Generalized Unimodular Gravity. https://doi.org/10.1142/s0218271817501073

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