Anatomy of geometrical destabilization of inflation

TL;DR

This paper investigates the process of geometrical destabilization during inflation, revealing it is a transient phenomenon prevented from indefinite growth by negative feedback, leading to a new stable field configuration.

Contribution

It provides the first detailed numerical analysis of the dynamics of geometrical destabilization, showing it results in a stable classical shift rather than runaway growth.

Findings

Geometrical destabilization is short-lived.

Negative feedback prevents indefinite growth of fluctuations.

Fields settle into a new classical configuration.

Abstract

We study geometrical destabilization of inflation with the aim of determining the fate of excited unstable modes. We use numerical lattice simulations to track the dynamics of both the inflaton and the spectator field. We find that geometrical destabilization is a short-lived phenomenon and that a negative feedback loop prevents field fluctuations from growing indefinitely. As a result, fields undergoing geometrical destabilization are merely shifted to a new classical configuration corresponding to a uniform value of the spectator field within a Hubble patch.