http://arxiv.org/abs/0709.0002 Searching for Inflation in Simple String Theory Models: An Astrophysical Perspective Mark P. Hertzberg (MIT), Max Tegmark (MIT), Shamit Kachru (Stanford), Jessie Shelton (Rutgers), Onur Ozcan (MIT) 24 pages, 5 figs (Submitted on 3 Sep 2007 (v1), last revised 3 Sep 2007 (this version, v2)) "...We analyze three explicit string models from the recent literature, each containing an infinite number of "vacuum" solutions. Our numerical investigation of some natural candidate inflatons, the so-called "moduli fields", fails to find inflation. We also find in the simplest models that, after suitable field redefinitions, vast numbers of these vacua differ only in an overall constant multiplying the effective inflaton potential, a difference which affects neither the potential's shape nor its ability to support slow-roll inflation. This illustrates that even having an infinite number of vacua does not guarantee having inflating ones. This may be an artifact of the simplicity of the models that we study. Instead, more complicated string theory models appear to be required, suggesting that explicitly identifying the inflating subset of the string landscape will be challenging." http://space.newscientist.com/article/dn12628-can-string-theory-accommodate-inflation.html Can string theory accommodate inflation?