Explosive particle production in non-commutative inflation

TL;DR

This paper analyzes a non-commutative inflation model, showing that rapid expansion causes particle production that ends inflation and transitions to radiation dominance, with analytical and numerical estimates of particle energy density and inflation duration.

Contribution

It provides the first detailed analytical and numerical analysis of particle production in non-commutative inflation models, estimating the end of inflation due to back-reaction effects.

Findings

Rapid particle production during non-commutative inflation terminates inflation.

Analytical estimates of particle energy density match numerical results.

Inflation ends after a calculable number of e-folds due to radiation back-reaction.

Abstract

We consider a model of inflation which has recently been proposed in the literature and where inflation is induced by corrections to the energy density coming from the non-commutativity of spacetime. We show that the very rapid inflationary expansion typical of this model is responsible for a burst of particle production which ends inflation and leads to a radiation-dominated phase. We analytically estimate the energy density of these particles and we confront the results with more precise numerical calculations. We estimate the number of inflationary e-folds before the back-reaction of the radiation energy density overcomes the non-commutative effects and terminate inflation naturally.