Angular correlation as a novel probe of supermassive primordial black
  holes
  We investigate the clustering property of primordial black holes (PBHs) in a
scenario where PBHs can explain the existence of supermassive black holes
(SMBHs) at high redshifts. We analyze the angular correlation function of PBHs
originating from fluctuations of a spectator field which can be regarded as a
representative model to explain SMBHs without conflicting with the constraint
from the spectral distortion of cosmic microwave background. We argue that the
clustering property of PBHs can give a critical test for models with PBHs as
the origin of SMBHs and indeed show that the spatial distribution of PBHs in
such a scenario is highly clustered, which suggests that those models may be
disfavored from observations of SMBHs although a careful comparison with
observational data would be necessary.
