Primordial black holes from supersymmetry in the early universe
  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.
