MULTIPLE INFLATION

Attempts at building a unified description of the strong, weak and ele ctromagnetic interactions usually involve several stages of spontaneou s symmetry breaking. We consider the effects of such symmetry breaking during an era of primordial inflation in supergravity models, In case s that these occur along flat directions at intermediate scales there will be a succession of short bursts of inflation which leave a distin ctive signature in the spectrum of the generated scalar density pertur bation, Thus measurements of the spectral index can directly probe the structure of unified theories at very high energy scales. An observed feature in the power spectrum of galaxy clustering from the APM surve y may well be associated with such structure. If so, this implies a ch aracteristic suppression of the secondary Doppler peaks in the angular power spectrum of temperature fluctuations in the cosmic microwave ba ckground. (C) 1997 Published by Elsevier Science B.V. PACS: 98.80.Cq; 04.65.+e; 98.65.Dx; 98.70.Vc.