Speaker
Description
A novel approach to quintessential inflation model building is studied, within the framework of α-attractors (motivated by supergravity theories), which naturally result in a scalar potential featuring two flat regions, the inflationary plateau and the quintessential tail. The "asymptotic freedom" of α-attractors, near the kinetic poles, suppresses radiative corrections and interactions, which would otherwise threaten to lift the flatness of the quintessential tail and cause a 5th-force problem respectively. Since this is a non-oscillatory inflation model, special attention is paid to the reheating of the Universe through instant preheating, which avoids gravitino overproduction and respects nucleosynthesis constraints. Inflationary observables are in excellent agreement with the latest CMB observations, while quintessence explains the dark energy observations without any fine-tuning. The model predicts potentially sizeable tensor perturbations (at the level of 1%) and a slightly varying equation of state for dark energy, to be probed in the near future. A distinct correlation between the produced gravitational waves and the running of the barotropic parameter of dark energy is a smoking gun of this scenario.
