On the Adiabatic Solution to the Polonyi/Moduli Problem

TL;DR

This paper investigates the adiabatic suppression mechanism as a solution to the Polonyi/moduli problem, analyzing conditions for its effectiveness, its limitations at different reheating temperatures, and extending the framework to various mediation models.

Contribution

It provides a comprehensive analysis of the adiabatic suppression mechanism's viability, including new constraints and extensions to different mediation scenarios.

Findings

Adiabatic suppression can mitigate the Polonyi problem at low reheating temperatures.

Thermal production of Polonyi particles constrains the reheating temperature.

Extensions to gauge and anomaly mediation are explored with derived bounds.

Abstract

One of the solutions to the cosmological Polonyi problem is to introduce a large coupling between the Polonyi field and the inflaton so that the Polonyi field adiabatically tracks the temporal minimum of the potential. We study general conditions for the adiabatic suppression mechanism to work, and find that a non-negligible amount of the Polonyi field is induced in the form of coherent oscillations at the end of inflation. In the case of low reheating temperature, this contribution is so small that it does not cause cosmological problems. On the other hand, this contribution may be significant for a relatively high reheating temperature and we still need some amount of tuning in order to avoid the Polonyi problem. We also point out that Polonyi particles produced from thermal plasma pose a severe constraint on the reheating temperature. Furthermore, we extend the original framework to include enhanced couplings of the Polonyi field with the visible particles as well as with itself, and derive upper bounds on the reheating temperature after inflation. We also investigate the adiabatic solution to the cosmological moduli problem in gauge and anomaly mediation.