Inflationary models with non-minimally derivative coupling. (20th September 2016)

• Record Type: Journal Article
• Authors: Yang, Nan; Fei, Qin; Gao, Qing; Gong, Yungui
• Is Part Of: Classical and quantum gravity. Volume 33:Number 20(2016:Oct.)
• Publication Date: 2016-09-20
• Subjects: inflation -- modified gravity -- power spectrum -- inflationary models; 98.80.Cq -- 98.80.-k -- 04.50.Kd; Quantum gravity -- Periodicals; Gravitation -- Periodicals; Relativity (Physics) -- Periodicals; Space and time -- Periodicals; Periodicals; 521.1
• DOI: 10.1088/0264-9381/33/20/205001
• Languages: English
• ISSNs: 0264-9381

Abstract

Abstract: We derive the general formulae for the scalar and tensor spectral tilts to the second order for the inflationary models with non-minimally derivative coupling without taking the high friction limit. The non-minimally kinetic coupling to Einstein tensor brings the energy scale in the inflationary models down to be sub-Planckian. In the high friction limit, the Lyth bound is modified with an extra suppression factor, so that the field excursion of the inflaton is sub-Planckian. The inflationary models with non-minimally derivative coupling are more consistent with observations in the high friction limit. In particular, with the help of the non-minimally derivative coupling, the quartic power law potential is consistent with the observational constraint at 95% CL.