Natural Supergravity inflation

Abstract

We identify a new mechanism in supergravity theories which leads to successful inflation without any need for fine tuning. The simplest model yields a spectrum of density fluctuations tilted away from scale-invariance and negligible gravitational waves. We demonstrate that this is consistent with the observed large-scale structure for a cold dark matter dominated, critical density universe. The model can be tested through measurements of microwave background anisotropy on small angular scales.

14 pages (revtex) including 3 figures (epsf); Minor changes to Introduction and discussion and modified Figure 1; to appear in Phys. Lett. B; Postscript also available from ftp://ftp.physics.ox.ac.uk/pub/local/users/sarkar/SugraInfl.ps.gz