Dimopoulos, Konstantinos and Donaldson Wood, Leonora and Owen, Charlotte (2018) Instant preheating in quintessential inflation with α-attractors. Physical Review D, 97 (6): 063525. ISSN 1550-7998
Abstract
We investigate a compelling model of quintessential inflation in the context of α-attractors, 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 nonoscillatory inflation model, we reheat the Universe through instant preheating. The parameter space is constrained by both inflation and dark energy requirements. We find an excellent correlation between the inflationary observables and model predictions, in agreement with the α-attractors setup. We also obtain successful quintessence for natural values of the parameters. Our 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.