NON-LOCAL INFLATION AROUND A LOCAL MAXIMUM

Abstract

It is shown that non-local, higher-derivative operators, which arise generically in string field theory, can act as additional sources of friction on the inflaton field as it rolls away from a maximum in its potential. Moreover, the cosmic dynamics can be quantified in terms of a local field theory, where the curvature of an effective potential has been suppressed. A prolonged phase of quasi-exponential expansion can therefore be realised with steep potentials that typically arise in particle physics models. We illustrate this effect within the context of p-adic string theory.