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arXiv · 1710.00682

Constant-roll Inflation in $f(T)$ Teleparallel Gravity

A. Awad·W. El Hanafy·G. G. L. Nashed·S. D. Odintsov·V. K. Oikonomou
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Abstract

We investigate in detail the implications of the constant-roll condition on the inflationary era of a scalar field coupled to a teleparallel $f(T)$ gravity. The resulting cosmological equations constitute a reconstruction technique which enables us to find either the $f(T)$ gravity which corresponds to a given cosmological evolution, or the Hubble rate of the cosmological evolution generated by a fixed $f(T)$ gravity. We also analyze in some detail the phase space of the constant-roll teleparallel gravity and we discuss the physical significance of the resulting fixed points and trajectories. Also we calculate the observational indices of a theory with given $f(T)$ gravity, and we discuss all the implications of the constant-roll condition on these. As we demonstrate, the resulting theory can be compatible with the current observational data, for a wide range of values of the free parameters of the theory.

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A. Awad, W. El Hanafy, G. G. L. Nashed, S. D. Odintsov, V. K. Oikonomou. 2018-07-13. Constant-roll Inflation in $f(T)$ Teleparallel Gravity. https://doi.org/10.1088/1475-7516%2F2018%2F07%2F026

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