https://doi.org/10.1140/epjc/s10052-023-11459-1
Regular Article - Theoretical Physics
Constant-roll inflation in modified 
gravity model using Palatini formalism
Department of Physics, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh, India
Received:
30
December
2022
Accepted:
2
April
2023
Published online:
17
April
2023
In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field 
with Ricci scalar R in a general form of . Using Palatini approach, we write its equivalent scalar-tensor form in the Einstein frame and then apply the constant-roll condition in the equation of motion for the inflaton field. Later the tensor-to-scalar ratio and the spectral index are calculated using the slow-roll parameters and the results obtained are matched with the Planck 2018 data. We found that the results agree nicely with the observations within the parameter regime under consideration.
© The Author(s) 2023
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