k-Essence Inflation Evading Swampland Conjectures and Inflationary Parameters

In this paper, we study the inflationary scenario in the realm of k-essence model and swampland conjectures. Taking into account three models of Chaplygin gas, such as generalized, modified, and generalized cosmic Chaplygin gas models, we discuss the equation of state (EoS) parameter omega, slow roll parameters (epsilon(phi),eta(phi)), curvature perturbation (P-s), tensor to scalar ratio (r), and scalar spectral index (ns). As regards the k-essence model, the coupling function as a function of scalar field L(phi) is used. We investigate the swampland conjecture and then find the value of zeta(phi), i.e., bound of second conjecture for these three models by unifying swampland conjecture and k-essence. We plot the EoS parameter omega, inflationary parameters plane r-ns and bound of swampland conjecture zeta(phi)-phi, which determine that the values of omega<-1 for each model, r, are r < 0.0094, r <= 0.0065, r <= 0.0067, and ranges for ns are [0.934,0.999],[0.9,0.999],[0.9,0.992] for generalized, modified, and generalized cosmic Chaplygin gas models, respectively, and compare their compatibility with the Planck data from 2018. Furthermore, we determine the bound for swampland conjecture as zeta(phi)<= 0.992, zeta(phi)<= 0.964,zeta(phi)<= 0.964 for generalized, modified and generalized cosmic Chaplygin gas models, respectively.

Automated summary

This paper investigates the inflationary scenario within the framework of k-essence model and swampland conjectures, focusing on three models of Chaplygin gas and discussing various parameters like equation of state, slow roll parameters, and curvature perturbation. The results show that the values of omega are less than -1 for each model, with different ranges for r and ns, and comparing their compatibility with the 2018 Planck data. Additionally, bounds for the swampland conjecture were determined for each model.