Swampland, axions, and minimal warm inflation

Abstract

Warm inflation has been noted previously as a possible way to implement inflationary models compatible with the dS swampland bounds. But often in these discussions, the heat bath dynamics are kept largely unspecified. We point out that the recently introduced minimal warm inflation [K. V. Berghaus, P. W. Graham, and D. E. Kaplan, J. Cosmol. Astropart. Phys. 03 (2020) 034], where an axionic coupling of the inflaton leads to an explicit model for the thermal bath, yields models of inflation that can easily fit cosmological observations while satisfying de Sitter swampland bounds, as well as the swampland distance bound and trans-Planckian censorship.