Spotted Inflation

TL;DR

This paper explores new mechanisms for generating curvature perturbations during inflation involving localized interactions called spots, which can induce inhomogeneous phase transitions and trigger warm inflation.

Contribution

It introduces the concept of spots from enhanced symmetric points affecting inflaton dynamics, a novel approach to curvature perturbation generation.

Findings

Spot interactions can cause inhomogeneous phase transitions.

Spots may initiate warm inflation in a cold universe.

Mechanisms for curvature perturbation generation are linked to spot-induced effects.

Abstract

We describe new scenarios of generating curvature perturbations when inflaton (curvaton) has significant interactions. We consider a ``spot'', which arises from interactions associated with enhanced symmetric point (ESP) on the trajectory. Our first example uses the spot to induce a gap to the field equation. We observe that the gap in the field equation may cause generation of curvature perturbation if it appears not simultaneous in space. The mechanism is similar to the scenario of inhomogeneous phase transition. Then we observe that the spot interactions may initiate warm inflation in the cold Universe. Creation of cosmological perturbation is discussed in relation to the inflaton dynamics and the modulation associated with the spot interactions.