Gravitational production of KK states

TL;DR

This paper investigates how Kaluza-Klein states are produced through gravitational effects in braneworld scenarios, analyzing their abundances and cosmological implications for fields like gravitinos and axions.

Contribution

It provides a phenomenological analysis of KK mode production and applies the results to specific fields, deriving constraints on extra-dimensional models.

Findings

KK modes are produced gravitationally with calculable abundances

Constraints on extra dimensions are derived from cosmological considerations

Applications to gravitinos and axions highlight model-specific implications

Abstract

Gravitational particle production in the context of braneworlds is considered from a phenomenological point of view. The production of KK modes for bulk fields is discussed and their abundances computed. The results have been applied to some specific fields such as gravitinos and axions, and their cosmologies have been outlined, exemplifying the constraints on the properties of the extra dimensional model in each case.