Scalar Cosmological Perturbations in M-theory with Higher Derivative Corrections

TL;DR

This paper studies scalar cosmological perturbations during M-theory driven inflation with higher derivative corrections, deriving the power spectrum and showing the spectral index approaches scale invariance.

Contribution

It provides an explicit analysis of scalar perturbations in M-theory inflation including higher curvature corrections, which was not previously detailed.

Findings

Scalar power spectrum is computed explicitly.

Spectral index approaches 1 under certain assumptions.

Higher derivative corrections influence the perturbation spectrum.

Abstract

We investigate the inflationary expansion of the universe induced by higher curvature corrections in M-theory. The inflationary evolution of the geometry is discussed in ref.[1], thus we succeed to analyse metric perturbations around the background. Especially we focus on scalar perturbations and analyse linearized equations of motion for the scalar perturbations. By solving these equations explicitly, we evaluate the power spectrum of the curvature perturbation. Scalar spectrum index is estimated under some assumption, and we show that it becomes close to 1.