Superheavy Q-Balls and Cosmology

McDonald, John (2026) Superheavy Q-Balls and Cosmology. Journal of Cosmology and Astroparticle Physics, 2026 (04): 050. ISSN 1475-7516

Text (pdf.pdf)
pdf.pdf - Published Version
Available under License Creative Commons Attribution.
Download (634kB)

Abstract

We propose a model for the cosmological formation of superheavy Q-Balls in the mass range 10-7 M ⊙ to 106 M ⊙. 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 ∼ 106 M ⊙ and diameter ∼ 100 light years, with a number density ∼ 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.