Gyroscopic Inflation

Abstract

We propose a new framework for multi-field inflation in which a nearly constant potential energy is maintained during inflation before decreasing rapidly, in a manner analogous to a classical top spinning upright for a long time before falling down. We provide the simplest realization of such dynamics as a well-controlled, weakly-coupled effective field theory with a global shift symmetry. Nonperturbative quantum gravitational effects, which break global symmetries, are suppressed in this model. Primordial gravitational waves may be within experimental reach.