Tracing Primordial Black Holes in Nonsingular Bouncing Cosmology
  We in this paper investigate the formation and evolution of primordial black
holes (PBHs) in nonsingular bouncing cosmologies. We discuss the formation of
PBH in the contracting phase and calculate the PBH abundance as a function of
the sound speed and Hubble parameter. Afterwards, by taking into account the
subsequent PBH evolution during the bouncing phase, we derive the density of
PBHs and their Hawking radiation. Our analysis shows that nonsingular bounce
models can be constrained from the backreaction of PBHs.
