  In recent work we have extended the theory that dark matter is composed of
primordial black hole (PBHs) to extremely high masses and made an assumption
that the holographic entropy bound is saturated. Astrophysicists have recently
suggested that PBHs are formed with electric charges Q, retain their charges
for the age of the universe, all charges have the same sign, and Q/M increases
with mass M. Adopting these assumptions and using an approximate formula
relating Q and M, it is here suggested that, for PBHs with over a trillion
solar masses, Coulomb repulsion can exceed gravitational attraction and that
electromagnetic properties of dark matter are a possible cause for the observed
accelerated cosmological expansion.
