Abstract:
The purpose of this thesis is to investigate the inflationary parameters
and swampland conjectures in the presence of scalar field and Chaplygin
gas models. We investigate the inflationary parameters such as slow roll
parameters, scalar power spectrum, tensor power spectrum, spectral in-
dex, tensor-to-scalar ratio in the presence of scalar field and Chaplygin gas
models and also discuss the recently proposed swampland conjectures. The
inflationary scenario is assumed to be working under a standard scalar field
having Γ as decay ratio. This decay ratio has dependence in the form of
generic power-law of scalar field φ along with thermal bath temperature T ,
that is, Γ(φ, T ) = Cφ
T a
φa−1
, where Cφ is dimensionless parameter and a is
inflation decay rate. Assuming that our model bends according to strong
dissipative regime (R À 1), we study the background and perturbative dy-
namics as well as inflationary observable as the scalar power spectrum PR,
scalar spectral index ns, dissipative ratio R, the tensor-to-scalar ratio r, run-
ning of the scalar spectral index dns
d ln k
and generalized ratio of Swampland
de-Sitter conjecture
T´V
V´ T
for three different potentials V (φ) =
3H2
inf
8π
e
2φ
p(φ+1) ,
V = M4
µ
φ
Mp
¶
2
µ
1 + β
φ2
M2
p
¶
and V = 3
4
M2(1 − e
√
2
3
φ)2 respectively.
