Extended constant-roll condition in non-canonical scalar field inflation
Abstract
In this work, we apply the extended constant-roll condition to non-canonical scalar fields. We use in particular two types of non-canonical fields, namely, the tachyon field and the Dirac-Born-Infeld (DBI) field. We assume, in particular, that the tachyon scalar field satisfies the condition ϕ̈ = α(ϕ)V′(ϕ)/V (ϕ), while the DBI scalar field satisfies the condition ϕ̈ = α(ϕ)V′(ϕ). We use the extended constant-roll condition to calculate the inflation indices for each of these non-canonical fields. In order to test the extended constant-roll condition, we use three types of potentials, namely chaotic potential, linear power-law potential and exponential potential, and choose power-law and exponential forms for the smooth function α(ϕ). It is then shown that the models under consideration are compatible with the latest Planck 2018 constraints.
- Publication:
-
International Journal of Geometric Methods in Modern Physics
- Pub Date:
- December 2023
- DOI:
- 10.1142/S0219887824500087
- Bibcode:
- 2023IJGMM..2050008M
- Keywords:
-
- Inflation;
- extended constant-roll condition;
- non-canonical scalar field