SIMPLE-MODEL OF LARGE-SCALE STRUCTURE FORMATION

We explore constraints on inflationary models employing data on large scale structure mainly from Cosmic Background Explorer (COBE) temperat ure anisotropies and Infrared Asronomy Satellite (IRAS) selected galax y surveys, taking care not to apply linear perturbation theory to data in the nonlinear regime. In models where the tensor contribution to t he COBE signal is negligible, we find the spectral index of density fl uctuations n must exceed 0.82. Furthermore, in inflation models which generate tensor fluctuations, these must contribute less than 20% of t he signal seen by COBE. The data favor cold plus hot dark matter model s with n close to unity and OMEGA(HDM) approximately 0.20-0.35. We pre sent realistic grand unified theories, including supersymmetric versio ns, which produce inflation with these properties.