Abstract:
In this thesis, we consider a warm in°ation universe model in the con-
text of generalized Chaplygin gas and modi¯ed Chaplygin gas by taking
Dirac-Born-Infeld non-canonical scalar ¯eld. We determine the two simple
potentials which are quartic potential and chaotic potential by considering
the ¯rst Friedmann equation. Also, we utilize the Anti-de-Sitter warp factor
for the Dirac-Born-Infeld in°ation. In each model, we consider the constant
sound speed and also determine the number of e-folds, scalar as well as ten-
sor power spectrum, scalar spectral index and tensor-scalar ratio in terms
of Á under slow-roll approximation. We establish that graphical behavior of
r ¡ N, ns ¡ N and ® ¡ N for Chaplygin gas models are well matched with
the 68% and 95% CL constraints of Planck 2018 TT,TE,EE+lowP+lensing
data. The graphical behavior represents that the models are compatible
with the Planck data in each case.
xiii
