Title: Warm Inflation, Its Implications for Natural Inflation and Other Recent Development
Abstract: Warm inflation provides an intriguing alternative to the standard inflationary paradigm, offering unique advantages in terms of model building. Unlike conventional models of inflation, which rely on the slow roll of an isolated scalar field, in warm inflation the inflaton is thermally coupled to a bath of radiation, continuously sourcing its production during the accelerated expansion. This dissipation not only alleviates the need for a separate reheating phase, but also provides an additional friction on top of Hubble friction, which effectively stabilizes the inflaton field at a scale lower than the Planck scale. In this talk, I will discuss the warm inflationary scenario in the context of natural inflation, specifically examining if the dissipation provides a mechanism to avoid the trans-Planckian decay constant f, undesirable from a model-building perspective. Additionally, if time permits, I will discuss more general aspects of warm inflation, such as the degree of fine tuning required to achieve an observationally viable period of inflation and the predominantly thermal nature of the generated scalar perturbations.