2015/06/30 by K. Sravan Kumar, João Marto, Paulo Vargas Moniz +1 · 1 citation
Physics and Astronomy · #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1088/1475-7516/2016/04/005
published as JCAP04(2016)005 · 17 pages, 6 figures, version accepted in JCAP
arxiv created 2016/04/04 · arxiv updated 2016/04/05
In this paper we consider the α-attractor model and study inflation under a non-slow-roll dynamics. More precisely, we follow the approach recently proposed by Gong and Sasaki \citeGong:2015ypa by means of assuming N=N(ϕ). Within this framework we obtain a family of functions describing the local shape of the potential during inflation. We study a specific model and find an inflationary scenario predicting an attractor at ns≈0.967 and r≈5.5×10-4. We further show that considering a non-slow-roll dynamics, the α-attractor model can be broaden to a wider class of models that remain compatible with value of r<0.1. We further explore the model parameter space with respect to large and small field inflation and conclude that the inflaton dynamics is connected to the α- parameter, which is also related to the Kähler manifold curvature in the supergravity (SUGRA) embedding of this model. We also comment on the stabilization of the inflaton's trajectory.