Hi Joe Z Dark matter has to exists in the sub-micro realm of the
universe.This is where are great accelerators can't move blackholes that
have a size of half a Planck length,and weigh as much as a
mountain(Hawking) You can't have to much matter(like blackholes in
space) as the missing 99% of gravity for they would create havoc.
There could be more sub-microscopic mini BH between the stars than the
protons in the stars.(Why not) Bert PS by say
blackhole 12 miles in diameter between the stars they would block off
and on light from stars,and this has not been detected.