  If the cosmological dark matter has a component made of small primordial
black holes, they may have a significant impact on the physics of the first
stars and on the subsequent formation of massive black holes. Primordial black
holes would be adiabatically contracted into these stars and then would sink to
the stellar center by dynamical friction, creating a larger black hole which
may quickly swallow the whole star. If these primordial black holes are heavier
than $\sim 10^{22} {\rm g}$, the first stars would likely live only for a very
short time and would not contribute much to the reionization of the universe.
They would instead become $10 - 10^3 M_\odot$ black holes which (depending on
subsequent accretion) could serve as seeds for the super--massive black holes
seen at high redshifts as well as those inside galaxies today.
