Warm Dark Energy
Alexandros Papageorgiou (University of Minnesota)

Motivated by some of the recent swampland conjectures, we study a model of dark energy in which a quintessence axion slowly rolls in a steep potential due to its interactions with a U(1) or an SU(2) gauge field. We compare the differences between the U(1) and SU(2) cases and specify the parameter space for which the model is compatible with observations. We also apply our methodology to studying the transition between a pre-inflationary era and inflation and note some interesting oscillatory effects in the particle production parameter which could lead to interesting phenomenology. Finally we analyze the potential of the "Warm Dark Energy" model to produce gravitational waves observable by PTA, CMB polarization or spectral distortion experiments and find a negative result.