Chaotic new inflation and formation of primordial black holes
  It is shown that in a number of scalar potentials with an unstable local maximum at the origin chaotic inflation is followed by new inflation if model parameters are appropriately chosen. In this model density fluctuation can have a large-amplitude peak on the comoving Hubble scale at the onset of the slow-roll new inflation and can result in formation of appreciable amount of primordial black holes on astrophysically interesting mass scales. 
Jun'ichi Yokoyama (Stanford U. and Yukawa Institute, Kyoto U.)