Superheavy Q-Balls and Cosmology

TL;DR

This paper presents a model for the cosmological formation of superheavy Q-Balls across a wide mass range, suggesting their potential roles in galaxy formation, SMBH development, and dark matter composition.

Contribution

It introduces a new scalar potential model inspired by broken scale invariance that enables formation of superheavy Q-Balls during the radiation era, with implications for cosmology.

Findings

Superheavy Q-Balls of mass up to 10^6 M_sun can form during the radiation era.

Q-Balls of various sizes could contribute to SMBH formation and dark matter.

The model produces Q-Balls with properties consistent with observational constraints.

Abstract

We propose a model for the cosmological formation of superheavy Q-Balls in the mass range $10^{-7} \, M_{\odot}$ to $10^{6} \, M_{\odot}$. The model is based on a hidden sector scalar potential motivated by broken scale invariance, for which analytic Q-ball solutions and numerical simulations of condensate fragmentation exist. We show that this potential can produce superheavy Q-balls during the radiation-dominated era. As an example, we show that it is possible to produce Q-balls of mass $ \sim \,10^{6} \, M_{\odot}$ and diameter $\sim$ 100 light years, with a number density $\sim 1$ per galaxy. Such early-forming superheavy Q-balls could play a role in galaxy and supermassive black hole (SMBH) formation. We also show that it is possible to form smaller mass Q-balls with large numbers per galaxy volume, that could form SMBH by merging. Finally, we show that it is possible to produce asteroid mass Q-balls that could account for all of the dark matter whilst remaining consistent with observational limits on MACHOs.