A non-equilibrium thermodynamical study of warm inflation and swampland conjectures

The present work deals with warm inflationary scenario from the viewpoint of non-equilibrium thermodynamics. Due to the interacting two-fluid system, the dissipative mechanism in warm inflation can be considered as effective bulk viscous pressure in second-order non-equilibrium description of thermodynamics. It is found that the interaction term is proportional to the enthalpy density of the formed particles. The warm inflation has been analysed using slow-roll approximation and an expression for the interaction term has been obtained. The formulation of warm inflation in the non-equilibrium thermodynamical prescription has been presented as a lemma. Lemma 2 shows the inter-relation between slow-roll approximation and quasistable radiation bath using the Friedmann equations. Finally, warm inflation has been examined from the point of view of swampland conjectures.