https://doi.org/10.1140/epjc/s10052-021-09619-2
Regular Article - Theoretical Physics
Viable intermediate inflation in the mimetic DBI model
1
Department of Theoretical Physics, Faculty of Science, University of Mazandaran, P. O. Box 47416-95447, Babolsar, Iran
2
ICRANet-Mazandaran, University of Mazandaran, P. O. Box 47416-95447, Babolsar, Iran
Received:
6
April
2021
Accepted:
7
September
2021
Published online:
20
September
2021
We study the intermediate inflation in the mimetic Dirac–Born–Infeld model. By considering the scale factor as 
, we show that in some ranges of the intermediate parameters b and 
, the model is free of the ghost and gradient instabilities. We study the scalar spectral index, tensor spectral index, and the tensor-to-scalar ratio in this model and compare the results with Planck2018 TT, TE, EE + lowE + lensing + BAO + BK14 data at 68% and 95% CL. In this regard, we find some constraints on the intermediate parameters that lead to the observationally viable values of the perturbation parameters. We also seek the non-Gaussian features of the primordial perturbations in the equilateral configuration. By performing the numerical analysis on the nonlinearity parameter in this configuration, we show that the amplitude of the non-Gaussianity in the intermediate mimetic DBI model is predicted to be in the range 
. We show that, with 
and 
, we have an instabilities-free intermediate mimetic DBI model that gives the observationally viable perturbation and non-Gaussianity parameters.
© The Author(s) 2021
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