Primordial black holes as dark matter and generators of cosmic structure
  Primordial black holes (PBHs) could provide the dark matter but a variety of
constraints restrict the possible mass windows to $10^{16} - 10^{17}$g,
$10^{20} - 10^{24}$g and $10 - 10^3M_{\odot}$. The last possibility is of
special interest in view of the recent detection of black-hole mergers by LIGO.
PBHs larger than $10^3 M_{\odot}$ might have important cosmological
consequences even if they have only a small fraction of the dark matter
density. In particular, they could generate cosmological structures either
individually through the "seed" effect or collectively through the "Poisson"
effect, thereby alleviating some problems associated with the standard cold
dark matter scenario.
