Primordial black holes from supersymmetry in the early universe

TL;DR

This paper explores how supersymmetric scalar fields in the early universe can lead to primordial black hole formation through Q-ball dynamics, potentially explaining dark matter within certain mass ranges.

Contribution

It introduces a mechanism where scalar condensates and Q-balls in supersymmetry can produce primordial black holes across a wide mass spectrum, including the entire observationally allowed range.

Findings

Primordial black holes can form from Q-ball fluctuations in supersymmetric models.

The mechanism can produce black holes over the full observational mass range.

Supersymmetry limits the maximum PBH mass to around 10^{23} grams.

Abstract

Supersymmetric extensions of the standard model generically predict that in the early universe a scalar condensate can form and fragment into Q-balls before decaying. If the Q-balls dominate the energy density for some period of time, the relatively large fluctuations in their number density can lead to formation of primordial black holes (PBH). Other scalar fields, unrelated to supersymmetry, can play a similar role. For a general charged scalar field, this robust mechanism can generate black holes over the entire mass range allowed by observational constraints, with a sufficient abundance to account for all dark matter in some parameter ranges. In the case of supersymmetry the mass range is limited from above by $10^{23}$g. We also comment on the role that topological defects can play for PBH formation in a similar fashion.