MSSM flat direction inflation

Abstract

We argue that all necessary ingredients for successful inflation are present in the flat directions of the minimal supersymmetric standard model (MSSM). Out of many gauge invariant combinations of the squarks, sleptons and Higgses, there are two flat directions, $\mathbf{LLe}$, and $\mathbf{udd}$, which are promising candidates for the inflaton. The model predicts more than $10^3$ e-foldings with an inflationary scale of $H_{\inf }\sim \mathcal{O}(1-10)$ GeV, provides a tilted spectrum $0.92\le n_s\le 1$ with an amplitude of ${\delta }_H\sim 10^{-5}$ and a negligible tensor perturbations. It yields a lower bound $\sim 340$ GeV on the sparticle masses which is within the reach of LHC. There is no gravitino or moduli problem in this model.

Comments: Talk given at the IPM School and Conference on Lepton and Hadron Physics, Tehran, Iran, May 15-20, 2006