Generation of perturbation after multi-field inflation

Abstract

We explore a new possibility that some inflaton fields in multi-field inflation models satisfy the observed value of the spectral index so that the curvature perturbation generated by them through post-inflationary dynamics may be relevant for the current observations. We illustrate this point using a simple and reasonable multi-field chaotic inflation model motivated from string theory. Possible non-Gaussianity and the tensor-to-scalar ratio are briefly addressed.

Comments: 8 pages, 1 figure; (v2) 9 pages, discussions expanded, to appear in Physics Letters B