https://doi.org/10.1140/epjp/s13360-020-00583-6
Regular Article
Inflation in f(R, T) gravity
1
Department of Astronomy, Osmania University, 500007, Hyderabad, India
2
UFCG - Universidade Federal de Campina Grande - Unidade Acadêmica de Física, 58429-900, Campina Grande, PB, Brazil
3
Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, 05508-090, São Paulo, SP, Brazil
4
Department of Mathematics, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, 500078, Hyderabad, India
d
pksahoo@hyderabad.bits-pilani.ac.in
Received:
30
March
2020
Accepted:
30
June
2020
Published online:
16
July
2020
The article presents modeling of inflationary scenarios for the first time in the f(R, T) theory of gravity. We assume the f(R, T) functional form to be 
, where R denotes the Ricci scalar, T the trace of the energy-momentum tensor and 
the model parameter (constant). We first investigated an inflationary scenario where the inflation is driven purely due to geometric effects outside of GR. We found the inflation observables to be independent of the number of e-foldings in this setup. The computed value of the spectral index is consistent with latest Planck 2018 dataset while the scalar to tensor ratio is a bit higher. We then proceeded to analyze the behavior of an inflation driven by f(R, T) gravity coupled with a real scalar field. By taking the slow-roll approximation, we generated interesting scenarios where a Klein Gordon potential leads to observationally consistent inflation observables. Our results make it clear-cut that in addition to the Ricci scalar and scalar fields, the trace of energy momentum tensor also plays a major role in driving inflationary scenarios.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2020
